Turbo 1991 z28 with A/C - Turbonetics tc76
#301
Re: Turbo 1991 z28 with A/C - Turbonetics tc76
hit the track tonight, running a 15 flat now at 95mph LOL, shaved 0.5 seconds off after switching to the 80# injectors and doing a bunch of tuning. That is 12 MPH down from where I was NA, and 2 seconds slower... My theory is that the hotside is such a restriction in the exhaust that the meager 3 psi the turbo is producing is not enough to make up for the restricted exhaust. Does that seem reasonable to anyone? I have a boost controller in the mail
I ran back to back with my intake off, no change. Retarded the timing 4 degrees, lost 0.1 and 2 mph.
My AFR's are right where they need to be (14.7 tapering down to 12.7 at 100kpa and slowly getting richer as I enter boost. I'm running 34-38* of timing and pulling 1.5* per PSI. The car is running GREAT, smooth, very little bucking etc, the best it's ever run to just drive around.
I'm confused
I ran back to back with my intake off, no change. Retarded the timing 4 degrees, lost 0.1 and 2 mph.
My AFR's are right where they need to be (14.7 tapering down to 12.7 at 100kpa and slowly getting richer as I enter boost. I'm running 34-38* of timing and pulling 1.5* per PSI. The car is running GREAT, smooth, very little bucking etc, the best it's ever run to just drive around.
I'm confused
#302
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Re: Turbo 1991 z28 with A/C - Turbonetics tc76
hit the track tonight, running a 15 flat now at 95mph LOL, shaved 0.5 seconds off after switching to the 80# injectors and doing a bunch of tuning. That is 12 MPH down from where I was NA, and 2 seconds slower... My theory is that the hotside is such a restriction in the exhaust that the meager 3 psi the turbo is producing is not enough to make up for the restricted exhaust. Does that seem reasonable to anyone? I have a boost controller in the mail
I ran back to back with my intake off, no change. Retarded the timing 4 degrees, lost 0.1 and 2 mph.
My AFR's are right where they need to be (14.7 tapering down to 12.7 at 100kpa and slowly getting richer as I enter boost. I'm running 34-38* of timing and pulling 1.5* per PSI. The car is running GREAT, smooth, very little bucking etc, the best it's ever run to just drive around.
I'm confused
I ran back to back with my intake off, no change. Retarded the timing 4 degrees, lost 0.1 and 2 mph.
My AFR's are right where they need to be (14.7 tapering down to 12.7 at 100kpa and slowly getting richer as I enter boost. I'm running 34-38* of timing and pulling 1.5* per PSI. The car is running GREAT, smooth, very little bucking etc, the best it's ever run to just drive around.
I'm confused
My car on 5 PSI will hit full spool around 3600 RPM, and it honestly just forces you more and more into your seat until you shift at 6K RPM. With a similiar sized turbo, I would expect yours to feel the same. Your mph is what would concern me. Even on 3 psi, I would think you should be at least around 115 mph traps. Even a crappy launch won't bring you down to 95 mph! Theres an issue somewhere and I'm sure you'll get it figured out. From what you say, it runs great mechanically, so I'm thinking it's just a minor issue with the turbo configuration itself...mainly the exhaust.
#303
Re: Turbo 1991 z28 with A/C - Turbonetics tc76
track times/mph, dyno numbers, same thing. I'm just at a loss on what to change now. My exhaust is 3" mandrel bent and is an open downpipe 5' long right now, I meant the t4 flange/turbo as the restriction in the exhaust.
I get full spool at 2400-3000 rpm in 2nd gear and above, 1st is like 3200
I get full spool at 2400-3000 rpm in 2nd gear and above, 1st is like 3200
#304
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Re: Turbo 1991 z28 with A/C - Turbonetics tc76
track times/mph, dyno numbers, same thing. I'm just at a loss on what to change now. My exhaust is 3" mandrel bent and is an open downpipe 5' long right now, I meant the t4 flange/turbo as the restriction in the exhaust.
I get full spool at 2400-3000 rpm in 2nd gear and above, 1st is like 3200
I get full spool at 2400-3000 rpm in 2nd gear and above, 1st is like 3200
#305
Re: Turbo 1991 z28 with A/C - Turbonetics tc76
2.5", its a .96 AR, I know mechanically everything is OK to make big power, like you just said I think I'm on too low of boost to make more power than I would have NA, while I'm waiting on my boost controller to arrive I was hoping to hear of similar experiences, so I dont have to worry about my tune being wayyyy off
#306
Re: Turbo 1991 z28 with A/C - Turbonetics tc76
here is a plot of the pass, the RPM is x1000, and everything else except boost is x10, boost is x1, I did that so it will scale and fit on one plot. I have attached the plot as a word document and the log and plot as a CSV excel file
Yes I realize I was shifting at just unker 5k, I was shifting at 5500, and 6000 my previous two passes and all three passes were within 0.1 and 1mph. When my car was NA I dynoed it and peak power was 4800 and fell of sharply after that, so when i ran it NA I shifted at 5000-5100 and my MPH was 83.5 in the 1/8, 106.5 in the 1/4.
I had computer issues and lost the first two logs from last night
Yes I realize I was shifting at just unker 5k, I was shifting at 5500, and 6000 my previous two passes and all three passes were within 0.1 and 1mph. When my car was NA I dynoed it and peak power was 4800 and fell of sharply after that, so when i ran it NA I shifted at 5000-5100 and my MPH was 83.5 in the 1/8, 106.5 in the 1/4.
I had computer issues and lost the first two logs from last night
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Re: Turbo 1991 z28 with A/C - Turbonetics tc76
I'm not really a tuner, but it seems like your running a ton of timing, even though your only at 3 psi. Your timing in boost is still up around 25-29 degrees. FYI, mine at 5 psi is at 17 degrees. Have you tried pulling your plugs to check if they are burning correctly?
I would lower your timing in boost and take away some fuel in boost. At only 3 psi, I would think you can run it around 13:1 AFR under WOT. I'm at around 12.8-12.9 AFR's under WOT.
I would lower your timing in boost and take away some fuel in boost. At only 3 psi, I would think you can run it around 13:1 AFR under WOT. I'm at around 12.8-12.9 AFR's under WOT.
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Re: Turbo 1991 z28 with A/C - Turbonetics tc76
Not sure which heads he is running but my L98 aluminums really like the timing, even at 13+ psi. One thing I notice from the log files is that the manifold air temp isn't really moving from about 138F degrees, regardless of driving mode. It seems the sensor is not mounted or perhaps is bad? Certainly 138 is too high. Even with my full stock foglight/trim installed I don't see that much on a hot day. When I had all of that opened up I was seeing ambient +5 max.
All the other things look fine though.. TPS, batt vol. Duty cycle is low.. under 20% on 80 lb/hr (I'm assuming you are not on E85 for now).. 19% supports about 165 hp, so I'm guessing that figure represents one half of a batch fire scheme so roughly your fueling supports 330 hp. Accounting for other inefficiencies, your mph shows ~300 crank hp.
More psi!
All the other things look fine though.. TPS, batt vol. Duty cycle is low.. under 20% on 80 lb/hr (I'm assuming you are not on E85 for now).. 19% supports about 165 hp, so I'm guessing that figure represents one half of a batch fire scheme so roughly your fueling supports 330 hp. Accounting for other inefficiencies, your mph shows ~300 crank hp.
More psi!
#309
Re: Turbo 1991 z28 with A/C - Turbonetics tc76
Aluminum l98 heads, still on 93 oct. Well I had 300RWHP on a dynojet NA, so 300 crank HP with basically no boost and a restrictive exhaust makes sense
The IAT's numbers are not correct, I have been meaning to get a new sensor (a plastic one) but I keep forgetting. The intercooler is cool to the touch when I open the hood but IAT's say 125F+, so I know the sensor is incorrect.
I checked my true timing today and my log data is dead nuts accurate. My true timing is right at 4 degress less than what it is set for in my timing tables
Astro - how are you determining duty cycle? I have autotune 1.7 for tunerpro but it shows 98% DC which is not correct. Good to hear I am low on timing
Ok so after consulting a bunch of sources, I have determined that my 29 degrees of timing is low for 3psi. I plan on turning it up to 35 degrees and seeing how that works, but at the same time the fact that in my pass data there is not a single cell that shows knock retard...does it makes snese that I am seeing ZERO knock retard? I did remove a pin into the ECM that I though was unused for $59 so I could use the pin insert for my WBO2, I hoping that was not a knock sensor/retard related pin. I'll try to figure out which one it was.
For those of you familiar with $59, where is the table(s) that controls knock retard? I want to make sure my knock control is correct before I start making the tune more aggressive
The IAT's numbers are not correct, I have been meaning to get a new sensor (a plastic one) but I keep forgetting. The intercooler is cool to the touch when I open the hood but IAT's say 125F+, so I know the sensor is incorrect.
I checked my true timing today and my log data is dead nuts accurate. My true timing is right at 4 degress less than what it is set for in my timing tables
Astro - how are you determining duty cycle? I have autotune 1.7 for tunerpro but it shows 98% DC which is not correct. Good to hear I am low on timing
Ok so after consulting a bunch of sources, I have determined that my 29 degrees of timing is low for 3psi. I plan on turning it up to 35 degrees and seeing how that works, but at the same time the fact that in my pass data there is not a single cell that shows knock retard...does it makes snese that I am seeing ZERO knock retard? I did remove a pin into the ECM that I though was unused for $59 so I could use the pin insert for my WBO2, I hoping that was not a knock sensor/retard related pin. I'll try to figure out which one it was.
For those of you familiar with $59, where is the table(s) that controls knock retard? I want to make sure my knock control is correct before I start making the tune more aggressive
Last edited by sailtexas186548; 06-02-2012 at 10:47 PM.
#310
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Re: Turbo 1991 z28 with A/C - Turbonetics tc76
You seriously heard that 29* of timing was low for a boosted app? I don't know many guys that run more than 22* under boost on a decently safe pump gas tune. 35* is N/A timing...Your problem is elsewhere, I'm sure! Like I said, my car felt like a monster at just 5 PSI on 17* of timing. Yours should be similiar. I would say before you go making the tune much more aggressive, add some boost and then see how it responds.
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Re: Turbo 1991 z28 with A/C - Turbonetics tc76
A friend has a turbo 355 with al.heads. His timing is
100kPa 36deg
150kPa 27deg
200kPa 23deg
250kPa 18deg
The newer LS ones dont like that much timing.
100kPa 36deg
150kPa 27deg
200kPa 23deg
250kPa 18deg
The newer LS ones dont like that much timing.
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Re: Turbo 1991 z28 with A/C - Turbonetics tc76
Is your temp sensor screwed into the intake? I know alot of people dont like them being there due to heatsoak from the manifold.
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Re: Turbo 1991 z28 with A/C - Turbonetics tc76
The only time heat soak of the MAT is an issue when installed in the plenum is when using a closed type MAT sensor. Using the open type it responds very quickly to changing intake temps, which to me shows that it is indicating actual air temp. Because the actual element is open it is directly exposed to the air it can respond quickly, the closed element sensor can only read the air after the brass has changed tempurature.
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Re: Turbo 1991 z28 with A/C - Turbonetics tc76
#315
Re: Turbo 1991 z28 with A/C - Turbonetics tc76
yeah the IAT sensor is the closed type, I read about the issue with it a few days ago now i need to get a different one LOL
ok well it seems like I am down on timing, thats good to hear. I checked my ture timing vs the data log vs the timing table and it seems that my true timing (digital timing light) is 4 degrees LESS than what is in my timing table, the data log seems pretty dam accurate to my true timing except at idle - true timing is 4 degrees less than the data log at idle. Any insight into this?
ok well it seems like I am down on timing, thats good to hear. I checked my ture timing vs the data log vs the timing table and it seems that my true timing (digital timing light) is 4 degrees LESS than what is in my timing table, the data log seems pretty dam accurate to my true timing except at idle - true timing is 4 degrees less than the data log at idle. Any insight into this?
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Re: Turbo 1991 z28 with A/C - Turbonetics tc76
there are several Spark tabels in code59, I'm sure you missed someone. My timing is dead on with tunerpro/timing light.
#317
Re: Turbo 1991 z28 with A/C - Turbonetics tc76
That is 12 MPH down from where I was NA, and 2 seconds slower... My theory is that the hotside is such a restriction in the exhaust that the meager 3 psi the turbo is producing is not enough to make up for the restricted exhaust. Does that seem reasonable to anyone? I have a boost controller in the mail
3psi is NOT much so basically you can keep your n/a tune up to that point. Run it mid 12's to 1 and keep full timing, maybe 1 deg pulled. I pulled ~2.5-3 deg by 4-5psi but it probably would have taken more. I run full 33-34 deg and air fuels are leaner at mid 12's to 1. Like natural aspirated to 2 psi. I'm going to try to get more aggressive with it to help spool on the new setup.
The fact that its on aluminum L98's means it will take even more timing than most heads for some reason. Old AFR 190's are like this too. I guess the chambers arent that efficient at burn. 36-38 deg WOT and cruise timings near 40 deg in some places. Newer heads like AFR 195's and the like make best power with lower 32-34 deg timing... vortecs are similar with best power around 28-32 deg depending.
You seriously heard that 29* of timing was low for a boosted app? I don't know many guys that run more than 22* under boost on a decently safe pump gas tune. 35* is N/A timing...
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Re: Turbo 1991 z28 with A/C - Turbonetics tc76
I can't remember my exact timing at 15 psi, 26-28 in the 4000+ range if memory serves. I had a problem for a while with less timing than in the tables on my Megasquirt. I have a temporary workaround using latency settings, but the timing is no longer stable when looking at it with a light. I'm not sure on the $59 but there should be retard tables based on the manifold air temp. 138 degrees is probably enough to knock 4 degrees off.
For duty cycle I just looked at the pulsewidth at a given rpm. There is a formula for the max pw at a given rpm. It's roughly 20ms for 6000 rpm. Then there are other factors such at latency, voltage and close times that come in to play. Anyway your pulsewidth at the peak logged rpm worked out to be the percentage I came up with. However there are many variables here.. how many injector firings per revolution, fuel pressure, etc.. so 300-325 is based on several assumptions.
After you fix the air temp, I bet your timing will match your table. Once you get the timing to match the tables, I agree with Orr that you need to be much higher with your boost. I would start at 7 psi at least. 8 is better and 9 is even better )
For duty cycle I just looked at the pulsewidth at a given rpm. There is a formula for the max pw at a given rpm. It's roughly 20ms for 6000 rpm. Then there are other factors such at latency, voltage and close times that come in to play. Anyway your pulsewidth at the peak logged rpm worked out to be the percentage I came up with. However there are many variables here.. how many injector firings per revolution, fuel pressure, etc.. so 300-325 is based on several assumptions.
After you fix the air temp, I bet your timing will match your table. Once you get the timing to match the tables, I agree with Orr that you need to be much higher with your boost. I would start at 7 psi at least. 8 is better and 9 is even better )
#319
Re: Turbo 1991 z28 with A/C - Turbonetics tc76
Good info guys thank you.
Does anyone have the part number for the open style iat sensor? Im at work on my phone so I can't look it up.
My boost control solenoid is here if I can get the iat sensor after work ill turn the boost up tonight!
Does anyone have the part number for the open style iat sensor? Im at work on my phone so I can't look it up.
My boost control solenoid is here if I can get the iat sensor after work ill turn the boost up tonight!
#320
Re: Turbo 1991 z28 with A/C - Turbonetics tc76
I think the gm part is 25036751. Wiring pigtail may be this one 12102620
Substitute Echlin # ECHTS5100
Should be same as this one.
http://www.diyautotune.com/catalog/g...tail-p-62.html
Think the syclone turbo trucks used something like this and code $59 was based on their $58 so it should work well. I plan on doing this myself.
AC delco part number for syclone IAT is AC213190 from what I see.
Substitute Echlin # ECHTS5100
Should be same as this one.
http://www.diyautotune.com/catalog/g...tail-p-62.html
Think the syclone turbo trucks used something like this and code $59 was based on their $58 so it should work well. I plan on doing this myself.
AC delco part number for syclone IAT is AC213190 from what I see.
Last edited by Orr89RocZ; 06-04-2012 at 12:13 PM.
#321
Re: Turbo 1991 z28 with A/C - Turbonetics tc76
I'll be honest that I haven't exactly seen anything WRT to a turbo on a 3rg gen that has really made me happy. Some came close (yours is better than many, I've seen one or 2 that I would say are cleaner, I don't want to tell you what I did and didn't like with yours so it doesn't change your answer, but if you want I can after you answer).
Anyway, I think posting your thoughts there would be interesting and helpful.
#324
Re: Turbo 1991 z28 with A/C - Turbonetics tc76
I would love to hear/see/whatever your ideas on this. I'm sure others would also. Can you post here for everyone to see, or maybe start another thread (or if you don't think others would be interested then just PM or email me). I've done a few setups, turbo and supercharged, on 3rd gens, 4th gens, mustangs (and other fox/SN chassis), even an infinity, and to be honest with you I've always thought they left something to be desired, even some of the better engineered high $$$ kits do (I've ended up re-engineering Stillen and KB supercharger kits).
I'll be honest that I haven't exactly seen anything WRT to a turbo on a 3rg gen that has really made me happy. Some came close (yours is better than many, I've seen one or 2 that I would say are cleaner, I don't want to tell you what I did and didn't like with yours so it doesn't change your answer, but if you want I can after you answer).
Anyway, I think posting your thoughts there would be interesting and helpful.
I'll be honest that I haven't exactly seen anything WRT to a turbo on a 3rg gen that has really made me happy. Some came close (yours is better than many, I've seen one or 2 that I would say are cleaner, I don't want to tell you what I did and didn't like with yours so it doesn't change your answer, but if you want I can after you answer).
Anyway, I think posting your thoughts there would be interesting and helpful.
There are a few other trick things I have in mind but I'll keep those in my head untill I can build them (I hope to do it in he next 2 years or less).
I'd like to hear your pros/cons of my set up, different perspective are always good stepping stones for progressive design.
And an update!
OK I got it ALL working (well everything if I'm correct thinking the MPH is in my data logs I have to verify to be sure though). I'm also back on TPV4 so I can use autotune, it saves soooo much time.
What was wrong was the pinout for the boost controller is supposed to be F2, not F4. In addition to that, there IS a required positive and ground wire for the solenoid, you cants just wire it up any which way (it's an inductor in there so duh it matters LOL can't believe I didn't catch that sooner).
Once that was done, it still would not regulate boost because I had no MPH signal. I had to move pin C1 to B12 and that supposedly fixed my MPH problem (gauge reads fine still), and now it shows desired boost and regulates boost! The boost control in $59 is MPH related to some extent even if it's superficial so it needs the signal to be present.
Once that was fixed it was not regulating boost to the correct number (was to high, 9 psi when I set it to 5). I played with some tables and searched online, the fix was the closed loop boost pressure upper threshold, original number was 9psi... go figure, until boost reaches that number it wont start to regulate boost, so that number needs to be the same as desired boost or less and it will work.
Now I'm boosting, the car pulls HARD, I have 0* knock retard at 5psi, 5* KR at 8 psi completely untuned so after a few tunes I should have it at zero. Then I'm going E85 so It'll really be safe detonation wise.
Hopefully I'll have some numbers from the track this friday that are better than 15's
#325
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Re: Turbo 1991 z28 with A/C - Turbonetics tc76
Great to hear! Now I really can't wait to see track times! BTW, just throwing this out of left field, but I need a 5th drive gear for a T56. You wouldn't happen to have any spare parts or know anybody that may have one, would you? They go for $200 new!! I'd like to not spend that lol.
#326
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Re: Turbo 1991 z28 with A/C - Turbonetics tc76
Depending on what boost your planning to run im wanting to say a 13 sec pass is realistic for your first time out. No more 15s for you I guarentee that. I picked up 4 seconds so far on my car from non turboed to turboed. from low mid 17s to mid low 13's now and its just a V6. So you can guess what your V8 can do compared to mine.
#328
Re: Turbo 1991 z28 with A/C - Turbonetics tc76
Depending on what boost your planning to run im wanting to say a 13 sec pass is realistic for your first time out. No more 15s for you I guarentee that. I picked up 4 seconds so far on my car from non turboed to turboed. from low mid 17s to mid low 13's now and its just a V6. So you can guess what your V8 can do compared to mine.
Shooting for 7.5 lbs on Friday
#329
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Re: Turbo 1991 z28 with A/C - Turbonetics tc76
I though you said 15s before? Man if you went 13's before the turbo then 12s should be nothing.... And 11's I wouldnt think would be hard if everything holds together right(drivetrain wise)
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Re: Turbo 1991 z28 with A/C - Turbonetics tc76
I would think you'll see at least a high 11 when everythings dialed in. I'm shooting for high 10's at 13x MPH with mine at 12-13 PSI.
#331
Re: Turbo 1991 z28 with A/C - Turbonetics tc76
I agree mid to high 11's are where I'll be with this motor once dialed in, bottom tens or better with new slugs/rods/clutch
Last edited by sailtexas186548; 06-13-2012 at 10:35 PM.
#332
Re: Turbo 1991 z28 with A/C - Turbonetics tc76
went to the track last night - 14.4 @ 96, I picked up almost a full second and 2 mph with just 2 psi more (5psi total) and a bit better tune. Timing is still the same between 30* and 35*, car is making real power now I just need to work out the boost control.
The car felt like I was pumping the brakes going down the track, so I plotted my boost, timing, KR, and WG duty cycle in excel. Just as I expected, my boost plot looked like a rolelr coaster, up-down-up-down-up-down and so on. I was getting 2* or so of KR in the last 300rpm of each gear, and timing was follinging boost exactly like I have it set to in my tune. The WGDC plot showed that my boost control is my issue, it would remain at 99% and build boost, then reach my 5psi setting and drop to 45-50% and the boost would fall of to 3psi, then WGDC jumps right back to 99% and boost hits 5psi, the nit starts over and my boost it 5, then 3, then 5, then 3, and so on. I just need to play with the bosot control tables a bit to get it sorted out, and maybe try a stiffer WG spring, 3psi right now LOL.
Somewhere between 5 and 3 psi the added boost is overcoming the exhaust restriction and the car really wakes up, It feels like a totally different car. I feel like there is easily 10mph more in just getting my boost to hold steady at 5psi.
The car felt like I was pumping the brakes going down the track, so I plotted my boost, timing, KR, and WG duty cycle in excel. Just as I expected, my boost plot looked like a rolelr coaster, up-down-up-down-up-down and so on. I was getting 2* or so of KR in the last 300rpm of each gear, and timing was follinging boost exactly like I have it set to in my tune. The WGDC plot showed that my boost control is my issue, it would remain at 99% and build boost, then reach my 5psi setting and drop to 45-50% and the boost would fall of to 3psi, then WGDC jumps right back to 99% and boost hits 5psi, the nit starts over and my boost it 5, then 3, then 5, then 3, and so on. I just need to play with the bosot control tables a bit to get it sorted out, and maybe try a stiffer WG spring, 3psi right now LOL.
Somewhere between 5 and 3 psi the added boost is overcoming the exhaust restriction and the car really wakes up, It feels like a totally different car. I feel like there is easily 10mph more in just getting my boost to hold steady at 5psi.
#333
Re: Turbo 1991 z28 with A/C - Turbonetics tc76
ok looking at my plots in more detail I can see that my boost is flucuating between my upper and lower closed loop boost threshholds, so I'm going to leave the upper one at 5psi and move my lower one to 4.8 (up from 3.62) to see how that responds. It's raining so I'm gonna have to wait a minute to test drive but I
m pretty sure it will fix my problem. It's weird that a closed loop table is affecting my bosot control but hey if it works, it works!
m pretty sure it will fix my problem. It's weird that a closed loop table is affecting my bosot control but hey if it works, it works!
#334
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Re: Turbo 1991 z28 with A/C - Turbonetics tc76
Run it in open loop only? Ive never ran closed loop personally in $59
Also look in the scalars, boost area, positive and negitive boost adjustment. Lower positive boost to stop spiking and raise the negitive boost so that it wont bottom out. I personally have mine very low on both. 2.12 and 2.19 DC% for the values. This could help, i guess its worth a try.
EDIT just read your last post..opps I read the first one. Let me know if changing those values works
Also look in the scalars, boost area, positive and negitive boost adjustment. Lower positive boost to stop spiking and raise the negitive boost so that it wont bottom out. I personally have mine very low on both. 2.12 and 2.19 DC% for the values. This could help, i guess its worth a try.
EDIT just read your last post..opps I read the first one. Let me know if changing those values works
#335
Re: Turbo 1991 z28 with A/C - Turbonetics tc76
yeah open loop all the time
are you saying make the upper/lower boost limits very close together, and right at my desired boost level? thats what i did and it helped, but boost still fluctuates 0.8 psi up and down up and down, I can feel it when I'm WOT. I changed the WGDC% from 45 to 55 hoping that would open the solenoid less and cause a more gradual boost drop but it seems to have had the opposite effect. I will try 35% tomorrow and see what that does. You have your WGDC at 2% ???
I also discovered I'm not getting MPH data still... so my WGDC is either 99% or whatever I have my 0 MPH cell set to
are you saying make the upper/lower boost limits very close together, and right at my desired boost level? thats what i did and it helped, but boost still fluctuates 0.8 psi up and down up and down, I can feel it when I'm WOT. I changed the WGDC% from 45 to 55 hoping that would open the solenoid less and cause a more gradual boost drop but it seems to have had the opposite effect. I will try 35% tomorrow and see what that does. You have your WGDC at 2% ???
I also discovered I'm not getting MPH data still... so my WGDC is either 99% or whatever I have my 0 MPH cell set to
#336
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Re: Turbo 1991 z28 with A/C - Turbonetics tc76
No the Wastegate Positive boost adjustment and the negitive boost adjustment is just is how much the WG duty cycle changes at a time if your desired boost level isnt met. Your ecm to a point, will adjust for the boost level via the wastegate and try to keep it as close to the desired boost level as possible. So you WG duty cycle table(F71_mph) is more of a fine tuning process as your ecm will adjust with that automatically.
Get that MPH to show up first before you start playing with the tables and scalers. I would think that if your ecm is not reading the MPH then your all your tables that have anything to do with MPH would be void and not work correctly.
Also just woundering but what is your Boost PSI Deadband? Its in the scalers, boost area. I Changed mine a while back since it was .75 psi. That value is what my boost would generly fluctuate. I know this scaler is rarely changed but it worked for my favor as mine is set to .30psi. Deadband is just the scope of where the boost trys to stay....I.E deadband of .50 psi would "try" and control the boost to stay from 5.75-6.25psi if the command boost was 6Psi.
Also just to add my boost fluctuates more then the deadband setting. Generly from 12.0-12.5 psi if my command boost is 12psi. But once I hit third gear there is no more fluctuation and the PSI stays solid. Its hard to contol the boost to stay at a set point when your shifting and causing random loads on the car. I can literly hear my wastegate cracking open in a 1/4 mile run at the track. But I have a screemer pipe off my wategate...
Gotta a datalogg I can check out? 30+ * of timing at 5 psi of boost just seems like alot, but if the car likes it.. thats fine then. But if your seeing KR on the Higher Rpm's the back it off and see if it goes away. If it goes away then you know that you have a tad too much timing up there or your too lean. That 1.5* per lbs of boost is a general rule but in my case I could never run more then 28* of timing at any boost level or I was catching KR. My total timing in the N/A tables is 36* but once I hit boost I drop down to 28* right off the start(115Kpa) Its gradual but the car just likes that amount of timing. Then down to 21*@ 12psi So just "give the car what she wants" not what you think it needs, and it will keep you happy for years to come.
Get that MPH to show up first before you start playing with the tables and scalers. I would think that if your ecm is not reading the MPH then your all your tables that have anything to do with MPH would be void and not work correctly.
Also just woundering but what is your Boost PSI Deadband? Its in the scalers, boost area. I Changed mine a while back since it was .75 psi. That value is what my boost would generly fluctuate. I know this scaler is rarely changed but it worked for my favor as mine is set to .30psi. Deadband is just the scope of where the boost trys to stay....I.E deadband of .50 psi would "try" and control the boost to stay from 5.75-6.25psi if the command boost was 6Psi.
Also just to add my boost fluctuates more then the deadband setting. Generly from 12.0-12.5 psi if my command boost is 12psi. But once I hit third gear there is no more fluctuation and the PSI stays solid. Its hard to contol the boost to stay at a set point when your shifting and causing random loads on the car. I can literly hear my wastegate cracking open in a 1/4 mile run at the track. But I have a screemer pipe off my wategate...
Gotta a datalogg I can check out? 30+ * of timing at 5 psi of boost just seems like alot, but if the car likes it.. thats fine then. But if your seeing KR on the Higher Rpm's the back it off and see if it goes away. If it goes away then you know that you have a tad too much timing up there or your too lean. That 1.5* per lbs of boost is a general rule but in my case I could never run more then 28* of timing at any boost level or I was catching KR. My total timing in the N/A tables is 36* but once I hit boost I drop down to 28* right off the start(115Kpa) Its gradual but the car just likes that amount of timing. Then down to 21*@ 12psi So just "give the car what she wants" not what you think it needs, and it will keep you happy for years to come.
Last edited by fasteddi; 06-17-2012 at 08:47 AM.
#337
Re: Turbo 1991 z28 with A/C - Turbonetics tc76
finally got MPH to show up - I had to "check" the magnetic sped sensor flag. the data is wayyyy off, its reading way high but i have a converter box for the t56 so thats why im sure. The boost is much more steady with a 0.2 deadband, it still spikes a bit then slowly drops off about 0.75psi total by the top of each gear.Thats easy enough to fix, it's close enough for now.
im at 30-33* timing up to 5psi, I just spent a TON of time smoothing my fuel table, it had a bunch of peaks and valleys from the autotuning, and now there is ZERO knock even at 125*+ IATS and very high rpm. My actual AFR is about 0.5 higher than desired in boost, it trends properly but is a bit high. So I added +1 to my entire f29x table 100kPa and up, hopefulyl that will bring it down into spec. If it does I'm going to change the bosot timing retard from 1.5*/PSI to 1.0*/PSI and see if that brings the KR back.
I'm to the point now that autotune is not improving my tune, but it has my fuel table close, so Im going to manually adjust the last little bit. Hopefully I can add in a bit more timing and feel the car really pick up power, then I'll turn the boost up to 7psi and see how it reacts
fasteddi - I'm emailing you my lastest data log and bin. I'm still having some weird problems with idle, when hot especially, the longer I drive the car the higher my IAT motor step counts gets, once over 90 it idles like total crap and after a minute or so the step count will drop to ~85 and it idles well again. I have every single idle table speed set to 800 except idle vs batt. volts where the rpm increases up from 800 as battery voltage decreses. My desired idle in the log is either 800, or 712???????? when it is 712 is when it's idleing and trying to die. I smoother my VE table in the idle cells and it seemed to help but the IAT count still acts weird and it idles inconsistantly...
just got back from another drive, the added fuel brough the afrs UP and the knock back, I give it fuel and now it then it wants even more! I think im moving in the right direction, it certainly feels better driving it
im at 30-33* timing up to 5psi, I just spent a TON of time smoothing my fuel table, it had a bunch of peaks and valleys from the autotuning, and now there is ZERO knock even at 125*+ IATS and very high rpm. My actual AFR is about 0.5 higher than desired in boost, it trends properly but is a bit high. So I added +1 to my entire f29x table 100kPa and up, hopefulyl that will bring it down into spec. If it does I'm going to change the bosot timing retard from 1.5*/PSI to 1.0*/PSI and see if that brings the KR back.
I'm to the point now that autotune is not improving my tune, but it has my fuel table close, so Im going to manually adjust the last little bit. Hopefully I can add in a bit more timing and feel the car really pick up power, then I'll turn the boost up to 7psi and see how it reacts
fasteddi - I'm emailing you my lastest data log and bin. I'm still having some weird problems with idle, when hot especially, the longer I drive the car the higher my IAT motor step counts gets, once over 90 it idles like total crap and after a minute or so the step count will drop to ~85 and it idles well again. I have every single idle table speed set to 800 except idle vs batt. volts where the rpm increases up from 800 as battery voltage decreses. My desired idle in the log is either 800, or 712???????? when it is 712 is when it's idleing and trying to die. I smoother my VE table in the idle cells and it seemed to help but the IAT count still acts weird and it idles inconsistantly...
just got back from another drive, the added fuel brough the afrs UP and the knock back, I give it fuel and now it then it wants even more! I think im moving in the right direction, it certainly feels better driving it
Last edited by sailtexas186548; 06-17-2012 at 04:56 PM.
#338
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Re: Turbo 1991 z28 with A/C - Turbonetics tc76
About the speed thing, You could try to go into the scalers, then the VSS area, then Road speed sensor consistant. What is your value there? Mine is 4000 roughly. IIRC They can be 8000, or 4000. I dont know forsure though. Mine was double the MPH in my starter bin and I put in 4000 as a value, which it then corrected the value to 4000.43 and my MPH problem was fixed. Sorry im no help in that area as you have a manual and some other things that I've never messed with or read about personally. But its worth a try as It won't hurt anything.
Thats good you got the boost to be more smooth and not go nuts. It looks good in your log although Id love to see the true MPH when you get it fixed up and see a good 10-80mph or so pull.
Dont worrie about smoothing the VE tables so much. Alot of people will agree that a smooth VE table can trash a tune. Just give the car fuel when it wants it. Ive never used autotune and basically can just look at the excel logs and add/remove fuel when needed. Its easy on WOT tuning I think. My VE table is a mess for being bumpy and such but thats mainly because there is a nice curve through that VE table that I always run through. Also from personal experience a car may need more fuel at 5k rpms/150kpa then less at 5200Rpms/150kpa and then more at 5500Rpms/150Kpa....you see where im going with this?
Give the car what the numbers on your excel format reads and youll be a step of the game. Auto tune is good for Part/throttle where there is 10,000 rows of data. I still use excel for that but it takes forever to tune Part throttle compared to WOT in my mind.
Keep in mind that the F77x table is a great tool for big chunks of fuel but should be used before the F29x in my mine which is the fine tuning. You could of done the same thing as you did in the F29x table in the F77x table as its just easier in my mind, but its preference I guess. (F77x) 84KPA and lower effects all of the Kpa under that including Idle.
About the idle, what does your car "usually" idle at when hot!? And what does it idle at when its only been running for about 5 minuets? Do you mean its hunts at idle when its hot? Its not the easiest thing to get that Idle right. I have about 14.0 AFR when somewhat warm and 14.8afr when HOT. I can live with that exspecially since it doesnt hunt at all anymore. A month or so back A few ppl helped me get my (F92 and F94) set up right. This helped greatly on my hunting issue and also made the car much more reponceive when free reving/little or no boost. What brand of injectors do you have?
Was it hot out when you were driving or were you driving for a bit? Those intake temps are really hot when your not boosting. Its not a big problem ATM as I ran up 150-160* in the 1/4 mile. But the starting point of my intake temps was never over 20* hotter then the outside air, even after a good hot drive. Is your Intake Air Temp sensor a open air one? And where is it mounted?
Thats good you got the boost to be more smooth and not go nuts. It looks good in your log although Id love to see the true MPH when you get it fixed up and see a good 10-80mph or so pull.
Dont worrie about smoothing the VE tables so much. Alot of people will agree that a smooth VE table can trash a tune. Just give the car fuel when it wants it. Ive never used autotune and basically can just look at the excel logs and add/remove fuel when needed. Its easy on WOT tuning I think. My VE table is a mess for being bumpy and such but thats mainly because there is a nice curve through that VE table that I always run through. Also from personal experience a car may need more fuel at 5k rpms/150kpa then less at 5200Rpms/150kpa and then more at 5500Rpms/150Kpa....you see where im going with this?
Give the car what the numbers on your excel format reads and youll be a step of the game. Auto tune is good for Part/throttle where there is 10,000 rows of data. I still use excel for that but it takes forever to tune Part throttle compared to WOT in my mind.
Keep in mind that the F77x table is a great tool for big chunks of fuel but should be used before the F29x in my mine which is the fine tuning. You could of done the same thing as you did in the F29x table in the F77x table as its just easier in my mind, but its preference I guess. (F77x) 84KPA and lower effects all of the Kpa under that including Idle.
About the idle, what does your car "usually" idle at when hot!? And what does it idle at when its only been running for about 5 minuets? Do you mean its hunts at idle when its hot? Its not the easiest thing to get that Idle right. I have about 14.0 AFR when somewhat warm and 14.8afr when HOT. I can live with that exspecially since it doesnt hunt at all anymore. A month or so back A few ppl helped me get my (F92 and F94) set up right. This helped greatly on my hunting issue and also made the car much more reponceive when free reving/little or no boost. What brand of injectors do you have?
Was it hot out when you were driving or were you driving for a bit? Those intake temps are really hot when your not boosting. Its not a big problem ATM as I ran up 150-160* in the 1/4 mile. But the starting point of my intake temps was never over 20* hotter then the outside air, even after a good hot drive. Is your Intake Air Temp sensor a open air one? And where is it mounted?
#339
Re: Turbo 1991 z28 with A/C - Turbonetics tc76
autotune is a good tool for ballparking WOT, and smoothing my VE table has helped more than any other change as far as backfiring, bucking, and smoothness at WOT. Big changes in ve cell to cell are really bad
my car idles at 800 right now, 14.1 afr, hot or cold its pretty much the same. If I can find what is causing the car to set a "desired idle" to 712 vs 800 I think that will solve it. It's not hunting or anything as long as the desired idle is where i set it, when it goes to 712 all hell breaks loose.
i have plenty of VE left in f29x so i'm staying away from 77x for now
its 93* ambient right now, so at the end of a 5psi pull im only at 125-130, I
m doing pretty well
my car idles at 800 right now, 14.1 afr, hot or cold its pretty much the same. If I can find what is causing the car to set a "desired idle" to 712 vs 800 I think that will solve it. It's not hunting or anything as long as the desired idle is where i set it, when it goes to 712 all hell breaks loose.
i have plenty of VE left in f29x so i'm staying away from 77x for now
its 93* ambient right now, so at the end of a 5psi pull im only at 125-130, I
m doing pretty well
#340
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Re: Turbo 1991 z28 with A/C - Turbonetics tc76
Yes you are
You had backfiring? and bucking? Well I guess your moving alot more fuel then I ever was. But whatever works works, im not trying to perswade you one bit. If I ever had the V4 Tunerpro I would have used the Autotune also, but just like V5 better. I have a" not so smooth" VE table but like I said I look for a constant AFR if at all possible and really dont care what the VE graph looks like. I cant think of the last time I looked at it since I tuned part throttle and I was in the N/A form.
You Idle steps are really 70-90? Mine is never that high ever. I still have a feeling you have a Vac leak somewhere, I really do. Are you sure you dont have one? Do the spray test everwhere? My step is 16 at Idle on ave.
You think 125* is high?? LOL wait till you run up 10psi or so for 11, 12seconds 0-110mph or so(in your case) in the 1/4 mile on a 90* day. Then watch the KR at the end of the run as the intake temps almost fly up for the last 1-2 seconds of the pull, just be carful when you get to that point thats all. More boost=heat of compression, not so bad in your case because of your efficent turbo depending on your map, but it will still go up as boost does.
Just talking here but whats your Comp ratio on your engine?
You had backfiring? and bucking? Well I guess your moving alot more fuel then I ever was. But whatever works works, im not trying to perswade you one bit. If I ever had the V4 Tunerpro I would have used the Autotune also, but just like V5 better. I have a" not so smooth" VE table but like I said I look for a constant AFR if at all possible and really dont care what the VE graph looks like. I cant think of the last time I looked at it since I tuned part throttle and I was in the N/A form.
You Idle steps are really 70-90? Mine is never that high ever. I still have a feeling you have a Vac leak somewhere, I really do. Are you sure you dont have one? Do the spray test everwhere? My step is 16 at Idle on ave.
You think 125* is high?? LOL wait till you run up 10psi or so for 11, 12seconds 0-110mph or so(in your case) in the 1/4 mile on a 90* day. Then watch the KR at the end of the run as the intake temps almost fly up for the last 1-2 seconds of the pull, just be carful when you get to that point thats all. More boost=heat of compression, not so bad in your case because of your efficent turbo depending on your map, but it will still go up as boost does.
Just talking here but whats your Comp ratio on your engine?
Last edited by fasteddi; 06-17-2012 at 06:42 PM.
#341
Re: Turbo 1991 z28 with A/C - Turbonetics tc76
Im 10.5:1 AL heads, I'm doing 0 to 100 MPH pulls on the street right now ever time I data log, IATS are not spiking and I just did pull #10 for the day, onlt had one cell of KR and it was only 0.8 degrees, with IATS in the upper 120's on 93 pump. I have 4th gear nailed down, 1-3 still need more fuel in the upper RPMS but the afr is steadily coming down to my desired settings. As soon as I get all 4 gears AFR in check for Just need to get the afr's in check a bit more and I'll start increasings the timing untill KR returns then back it off a bit.
I can feel the car really moving in the lower PRMS but its still not boosting enough to really make much power at higher RPMs -it's getting turned up soon!
I can feel the car really moving in the lower PRMS but its still not boosting enough to really make much power at higher RPMs -it's getting turned up soon!
#342
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Re: Turbo 1991 z28 with A/C - Turbonetics tc76
Awsome! As your boost increase you really start to have some fun!! 0-100Mph happens fast hu?
10.5:1 comp? Watch your KR as you increase the cylinder pressure(boost)! But you watch kr good so you'll be fine. Im 8.5:1 comp so I have a gutless car without a turbo but a great engine to boost at the same time.
10.5:1 comp? Watch your KR as you increase the cylinder pressure(boost)! But you watch kr good so you'll be fine. Im 8.5:1 comp so I have a gutless car without a turbo but a great engine to boost at the same time.
#343
Re: Turbo 1991 z28 with A/C - Turbonetics tc76
eh 0-50 is feeling fast now but my top end is not any faster than NA so its not feeling all that fast yet but its enough to have fun with.
I'll be going e85 in the future so 10.5:1 will be about perfect for a street car - its nice to have low end still.
Going for a final drive for the day, hoepfully zero knock, i jsut added MORE fuel for the 4th time! it just wants more and more
I'll be going e85 in the future so 10.5:1 will be about perfect for a street car - its nice to have low end still.
Going for a final drive for the day, hoepfully zero knock, i jsut added MORE fuel for the 4th time! it just wants more and more
#344
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Car: 1991 Camaro RS
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Transmission: ATI pro th350 sfi case. TSI 5500 st
Axle/Gears: Strange S60 4:10s
Re: Turbo 1991 z28 with A/C - Turbonetics tc76
Just keep giving it what it wants. e85 will work out well for you! Im just now getting on the alky injection and my car just loves the stuff.
#345
Re: Turbo 1991 z28 with A/C - Turbonetics tc76
aight so I keep adding fuel, around +1 VE in all of my boost cells and make two pulls then look at the log - the afrs are SLOWLY coming into spec, and the first pass has almost zero knock, then i wait one minute and do a second pull, the second pull has 2-4 degrees of KR, IATS are the same, afrs behave the same, but there is knock on the second pass. I'm guessing hot spots and/or heat soak are casuing some knock on the second pass(I let the car sit for 0.5 to 1 hour between logs to cool).
I'm planning on driving the car for an hour on the highway for an hour to keep it hot, and do a 0-100 pull every ten minutes to get some real consistant data. It's also 90+ ambient here, only down to 86 at night, so the fact that I'm only getting a tiny bit of KR on the second of back to back pulls does not concern me. The knock is always at 5k rpm so Imay pull some timing there also
I'm planning on driving the car for an hour on the highway for an hour to keep it hot, and do a 0-100 pull every ten minutes to get some real consistant data. It's also 90+ ambient here, only down to 86 at night, so the fact that I'm only getting a tiny bit of KR on the second of back to back pulls does not concern me. The knock is always at 5k rpm so Imay pull some timing there also
#346
Re: Turbo 1991 z28 with A/C - Turbonetics tc76
no tune updates work has been crazy this week, but here is a pic comparing my old and IAT sensors. I know a plastic sy/ty one is better but this works for now. I may cut the metal cage off to further reduce heat soak issues
#348
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Car: 1991 Camaro RS
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Transmission: ATI pro th350 sfi case. TSI 5500 st
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Re: Turbo 1991 z28 with A/C - Turbonetics tc76
Where are you guys getting those IAT sensors? I swear mine is a "open core" one although its metal.
#349
Re: Turbo 1991 z28 with A/C - Turbonetics tc76
^ open metal IAT's at any auto parts store, but the really good plastic ones you have to order.
Ok so an update, I put a full 3" exhaust on the car, much more pleasant to drive and now I can listen to what the car is doing rather than the obnoxious exhaust.
I have put about 1000 miles on the car this summer, with the STOCK dual fans it stays cool even in Houston traffic in 100+ degree temps so yes, a clean stock radiator and working fans are all you need for these cars
Last night I was on the freeway and heard an exhaust leak start, and noticed my AFR's going lean... great something on the new exhaust wasn't quite right not big deal I KNOW my tune is ok so I'll drive home. About 15 minutes later BANG!!!! followed by the sounds of bolts shooting around the engine bay and then I see bolts behind my on the road.... and now the exhaust leak is HUGE and AFR gauge is reading AIR. Pull over, pop the hood, all three collector bolts had backed out on the drivers side headers and the crossover was no longer connected to the header :haha:
When I got home I found a collector bolt nut on the garage floor, and well that explained a lot. I never noticed the bolts backing out before, even though I checked them every once in a while but apparently they did back out!
It's an easy fix, and I'm hoping it's been leaking for a while causing some tuning issues since I do all my tuning of of the AFR readings.
I'm still fighting a boost control issue, Boost comes up fast and hits my 5psi target (no spike) then follows a sine wave pattern between 5 and 3.8 PSI, and it sounds like I am having compressor surge. I'm not sure if thats due to a hot-side leak, the turbo being too large to be spooled and only make 5psi on this little motor, a boost controller/waste gate issue, or what. I need to take the controller off and see how it behaves
Ok so an update, I put a full 3" exhaust on the car, much more pleasant to drive and now I can listen to what the car is doing rather than the obnoxious exhaust.
I have put about 1000 miles on the car this summer, with the STOCK dual fans it stays cool even in Houston traffic in 100+ degree temps so yes, a clean stock radiator and working fans are all you need for these cars
Last night I was on the freeway and heard an exhaust leak start, and noticed my AFR's going lean... great something on the new exhaust wasn't quite right not big deal I KNOW my tune is ok so I'll drive home. About 15 minutes later BANG!!!! followed by the sounds of bolts shooting around the engine bay and then I see bolts behind my on the road.... and now the exhaust leak is HUGE and AFR gauge is reading AIR. Pull over, pop the hood, all three collector bolts had backed out on the drivers side headers and the crossover was no longer connected to the header :haha:
When I got home I found a collector bolt nut on the garage floor, and well that explained a lot. I never noticed the bolts backing out before, even though I checked them every once in a while but apparently they did back out!
It's an easy fix, and I'm hoping it's been leaking for a while causing some tuning issues since I do all my tuning of of the AFR readings.
I'm still fighting a boost control issue, Boost comes up fast and hits my 5psi target (no spike) then follows a sine wave pattern between 5 and 3.8 PSI, and it sounds like I am having compressor surge. I'm not sure if thats due to a hot-side leak, the turbo being too large to be spooled and only make 5psi on this little motor, a boost controller/waste gate issue, or what. I need to take the controller off and see how it behaves
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Car: 89 RS 89 iroc 87 firebird
Engine: 3.1 Turbo/ 355 twin turbo
Transmission: a4 w/ 4500 stall/ a4 / t5
Axle/Gears: strange s60 /w 3:42's
Re: Turbo 1991 z28 with A/C - Turbonetics tc76
i prefer the open metal ones, dont cut the cage off it it helps support the guuts of the sensor