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Organized Drag Racing and AutocrossDrag racing and autocross discussions and questions. Techniques, tips, suggestions, and "what will I run?" questions.
I havent looked into it nor ever even bothered to mess with 700r4 governors but is there a rough guideline of how much weight gives what rpm to shift at? I always thought it was a trial and error thing and a pita so manually doing it was always easiest
I really think it's the rpms hurting the full pull...
RPM is everything. Power is just to overcome the load behind it. Dudes over in Amboy New Jersey just ran a nine second pass at Atco Dragway naturally aspirated in a stock block four banger. I usually go to Amboy to tune on the street and on the GSP... you know how many times I ran into those guys on the street? Those K-Series are everywhere lol. Even when I had the turbo on the GTA, I still hesitated from a roll, and I normally never do lol...
The only way to know is to do it and see if it changes the slip. Or put it on a dyno to know exactly what the rpm range is and you can then determine the exact optimum shift rpm given the average power numbers under the curve
The only way to know is to do it and see if it changes the slip. Or put it on a dyno to know exactly what the rpm range is and you can then determine the exact optimum shift rpm given the average power numbers under the curve
The shop were our car was done he is moving soon so he will dyno it once he sets it back up..but I'll try it at the track and play with the different shift points and see what it does..thanks for the help guys.
whereever it shifted last time out try adding 200 rpm each pass and see where it goes
No I'm having a hard time figuring out how to download the logs im seeing I need a sd card reader to use into my laptop and I find the software to download to my laptop im just confused on why I need a sd card reader ..lol
I wish I had the scientific knowledge to guide you on what to do, but I can only go from my recent experiences with my new build. I also agree you should shift higher. However, my next time out at the track i might try to shift the 1-2 shift lower than the 2-3 shift. I feel like I am wasting time above 6,000 rpms in 1st gear when instead I could have shifted into 2 and then gone through 2 into 3 sooner, thereby getting me closer into the meat of my 3dr gear powerband right at the finish line.
My current best pass was when I shifted 1-2 at 6,048 rpms and the 2-3 shift at 6,400 Most other passes, although they were just 1-thenth slower I had revved out 1st gear and had it on the 6,500 rpm limiter. I don't know if its normal to shift the 1-2 shift earlier compared to the 2-3 shift, but that is what i want to keep playing with. I have a B&M rachet megashifter so I can bang it into each gear. This shifter has been in the car for 14 years and is still crisp, solid, and relaiable.
I wish I had the scientific knowledge to guide you on what to do, but I can only go from my recent experiences with my new build. I also agree you should shift higher. However, my next time out at the track i might try to shift the 1-2 shift lower than the 2-3 shift. I feel like I am wasting time above 6,000 rpms in 1st gear when instead I could have shifted into 2 and then gone through 2 into 3 sooner, thereby getting me closer into the meat of my 3dr gear powerband right at the finish line.
My current best pass was when I shifted 1-2 at 6,048 rpms and the 2-3 shift at 6,400 Most other passes, although they were just 1-thenth slower I had revved out 1st gear and had it on the 6,500 rpm limiter. I don't know if its normal to shift the 1-2 shift earlier compared to the 2-3 shift, but that is what i want to keep playing with. I have a B&M rachet megashifter so I can bang it into each gear. This shifter has been in the car for 14 years and is still crisp, solid, and relaiable.
Honestly im recommending her just shift 2nd into 3rd ...1st seemed great she even said it felt even on the 2 to 3 shift 1st to 2nd was fine..I think 2nd needs to be brought up higher into 3rd and she should see an ET and mph improvement.. we just have to get the better tires on or heat the hell out of the nittos so she can really launch this off the line... a 1.67 60ft rolling off that's pretty impressive says it's got gobs of low end torque..I just hope it has more on top..I dont think the oil being sucked in thru the pcv helped any either
I wish I had the scientific knowledge to guide you on what to do, but I can only go from my recent experiences with my new build. I also agree you should shift higher. However, my next time out at the track i might try to shift the 1-2 shift lower than the 2-3 shift. I feel like I am wasting time above 6,000 rpms in 1st gear when instead I could have shifted into 2 and then gone through 2 into 3 sooner, thereby getting me closer into the meat of my 3dr gear powerband right at the finish line.
My current best pass was when I shifted 1-2 at 6,048 rpms and the 2-3 shift at 6,400 Most other passes, although they were just 1-thenth slower I had revved out 1st gear and had it on the 6,500 rpm limiter. I don't know if its normal to shift the 1-2 shift earlier compared to the 2-3 shift, but that is what i want to keep playing with. I have a B&M rachet megashifter so I can bang it into each gear. This shifter has been in the car for 14 years and is still crisp, solid, and relaiable.
You have the holley sniper right you know how to data log im.so confused on how to...lol .I use diablosport on my hemi cars that's even to use and data log compared to this...lol
I wish I had the scientific knowledge to guide you on what to do, but I can only go from my recent experiences with my new build. I also agree you should shift higher. However, my next time out at the track i might try to shift the 1-2 shift lower than the 2-3 shift. I feel like I am wasting time above 6,000 rpms in 1st gear when instead I could have shifted into 2 and then gone through 2 into 3 sooner, thereby getting me closer into the meat of my 3dr gear powerband right at the finish line.
My current best pass was when I shifted 1-2 at 6,048 rpms and the 2-3 shift at 6,400 Most other passes, although they were just 1-thenth slower I had revved out 1st gear and had it on the 6,500 rpm limiter. I don't know if its normal to shift the 1-2 shift earlier compared to the 2-3 shift, but that is what i want to keep playing with. I have a B&M rachet megashifter so I can bang it into each gear. This shifter has been in the car for 14 years and is still crisp, solid, and relaiable.
Well, if the picture below was my dyno graph...
I see peak power is at 6000 but is essentially flat from 5800-6200. I most certainly would not shift at 6000 and give up some of that top end.
Then from data logs, I'd observe where 2nd gear picks up after the shift. I'm guessing with a 700R4 gear ratio that it'll be less than 4000 if the shift was from 6200. This is falling in below peak torque which is 4800 (but again more or less flat from 4600-5000). (6200 / 3.06) x 1.62 = 3282. Add something for converter slip. 10% ? So, with the higher shift RPM and crappy gear split, you're closer to peak torque rather than shifting early and having to accelerate into the peak for a longer period of time.
At least that's my take on it. The 2-3 shift has a better spread so 6200 (again taking advantage of that nice flat power curve) drops to (6200 / 1.62) = 3827. That's still 1000 RPM to burn through to get to the sweet spot.
By the way, bouncing off the limiter will always be slower...Move the limiter up a couple hundred RPM, set the shift light at 6200 and go. There will probably be a couple hundred RPM overspeed on the shift / shift reaction time so adjust accordingly.
My two cents there.
Now this is where a better gear split pays off at the track.
First transmission I ever rebuilt was a Muncie M22. That's the close ratio version.
First Gear 2.20:1 Second Gear 1.64:1 Third Gear 1.28:1 Fourth Gear 1:01
Imagine that RPM window. 6200 drops to 4600 on the 1-2. 6200 drops to 4800 on the 2-3...that's why these M22 equipped cars were fast at the track and made use of a peaky HP engine spec.
The engine from the graph above makes a lot of power. Use it.
As for hemi, totally yes. Get in on the dyno and get a printout. Don't be too concerned about the actual number produced as chassis dynos are notorious for being left, right and centre. It's where the peaks are that are important.
But the best test, as has been pointed out is to get out and race. Experiment. don't be afraid to go slower. You'll never know otherwise.
... a 1.67 60ft rolling off that's pretty impressive ...I dont think the oil being sucked in thru the pcv helped any either
1.67 is impressive. Especially with a soft start. Yep. Slicks. Maybe a little footbrake action. As ZMAN pointed out, the highest flash stall generally comes from mashing the throttle off idle. In bracket racing this will mean adjusting your reaction accordingly. But for test and tune, it makes little difference. Unless it's the driver being tuned.
As for the PVC, how do you have your lines running? From and to? And the breather is where?
I had an issue with a lot of blow-by on an worn out engine. My fix was a oil separator / catch can between the PCV valve and the intake manifold / carb base. It didn't collect a lot of crap, but it did work.
1.67 is impressive. Especially with a soft start. Yep. Slicks. Maybe a little footbrake action. As ZMAN pointed out, the highest flash stall generally comes from mashing the throttle off idle. In bracket racing this will mean adjusting your reaction accordingly. But for test and tune, it makes little difference. Unless it's the driver being tuned.
As for the PVC, how do you have your lines running? From and to? And the breather is where?
I had an issue with a lot of blow-by on an worn out engine. My fix was a oil separator / catch can between the PCV valve and the intake manifold / carb base. It didn't collect a lot of crap, but it did work.
I hope it's not blow!!! The breather is in the passenger valve cover and the pcv is on the drivers side going right into the first performance TB I think its in a bad spot the hose was wet...I bought a catch can so im.going to run the pcv to the catch can the from the catch can to the TB think that is ok?
As Justin rightly pointed out, the only way to know if it works, is to test it out. Met up with two members on this board yesterday not too far from us Gerard, both running Z28's. They are down to run at any track, as am I. Lets put this together and all meet up somewhere, Island, Atco, wherever. Not out for blood lol, this is all in fun, so no sneaking to the tracks without us...
Trying to get my buddies from NYC to join us as well, but I need an actual date to work with...
I...I bought a catch can so im.going to run the pcv to the catch can the from the catch can to the TB think that is ok?
Yes. That's how mine is routed. Breather on the passenger side, PCV valve on the driver's side, then to the catch can and on to the base of the carburetor.
Personally, I'd like to eliminate it altogether but that's not entirely practical. Especially for a multipurpose vehicle such as my own.
As Justin rightly pointed out, the only way to know if it works, is to test it out. Met up with two members on this board yesterday not too far from us Gerard, both running Z28's. They are down to run at any track, as am I. Lets put this together and all meet up somewhere, Island, Atco, wherever. Not out for blood lol, this is all in fun, so no sneaking to the tracks without us...
Trying to get my buddies from NYC to join us as well, but I need an actual date to work with...
- Rob
Rob definitely give me a week or so we can set something up I'm waiting on the catch can and couplers to come in to re do the snorkel to TB pipe .. might try the 555rs one more time too if they dont do good we have the MT drag radials to throw on.
Personally, I'd like to eliminate it altogether but that's not entirely practical. Especially for a multipurpose vehicle such as my own....
Just do what I did, no catch can even needed because you'll be grabbing the blow by from a lower source. Run -10 or -12an oil line from block off plate to fitted passenger side valve cover, then run another PCV on the passenger side that also goes to the throttle body, but attach it to a timed port (charcoal canister port), not a full vacuum like the drivers side. The passenger cylinder head becomes the catch can. Works well....
Just do what I did, no catch can even needed because you'll be grabbing the blow by from a lower source. Run -10 or -12an oil line from block off plate to fitted passenger side valve cover, then run another PCV on the passenger side that also goes to the throttle body, but attach it to a timed port (charcoal canister port), not a full vacuum like the drivers side. The passenger cylinder head becomes the catch can. Works well....
- Rob
we dont have a timed port anymore the new revision TB got rid of it...lol it has only consistent ports
If I may offer an opinion, I'd say skip the Nittos as it's been demonstrated that they're not up to the task. Go for the Mickey T's.
I know were eventually going to the MTs but my wife is a little stubborn she wants one more go with the nittos she is going to try going thru the water box and heating them up a hell of alot more...lol
we dont have a timed port anymore the new revision TB got rid of it...lol it has only consistent ports...
It doesn't have to be timed. I chose to use a timed port because the drivers side PCV uses a full manifold vacuum port. You can use a full vacuum port on the throttle body as well if need be. All that is needed is the fitting to be added to the passenger valve cover. I'm running standard chrome valve covers, so drilling and tapping into it with the fitting was no loss...
It doesn't have to be timed. I chose to use a timed port because the drivers side PCV uses a full manifold vacuum port. You can use a full vacuum port on the throttle body as well if need be. All that is needed is the fitting to be added to the passenger valve cover. I'm running standard chrome valve covers, so drilling and tapping into it with the fitting was no loss...
Take your dyno data and put it in excel. Rpm and hp columns
then based on gear ratios, and converter speed/slip, you can get an idea how much rpm drop there will be on the shift. Account for slip a few %
from that rpm range, highlight the cells off your dyno information between that rpm range in your hp column. Excel will display the average. Find the rpm range that has the highest average that is where you shoild shift to see best times
If your holley is setup in VE and you are confident in the afr ratio thru the pull then you can even plot rpm vs ve value and use that to find highest average ve value. That also should approximate best average hp
Only one on my phone, you can see the rest when we get to the track lol. You just need to buy a block off plate with AN fitting already in tact. Rest is very easy...
- Rob
Last edited by Street Lethal; 09-24-2020 at 12:44 PM.
Reason: Reducing Size of Picture....
Take your dyno data and put it in excel. Rpm and hp columns
then based on gear ratios, and converter speed/slip, you can get an idea how much rpm drop there will be on the shift. Account for slip a few %
from that rpm range, highlight the cells off your dyno information between that rpm range in your hp column. Excel will display the average. Find the rpm range that has the highest average that is where you shoild shift to see best times
Your getting very technical let me learn how to data log 1st...🤣🤣🤣🤣
As Justin rightly pointed out, the only way to know if it works, is to test it out. Met up with two members on this board yesterday not too far from us Gerard, both running Z28's. They are down to run at any track, as am I. Lets put this together and all meet up somewhere, Island, Atco, wherever. Not out for blood lol, this is all in fun, so no sneaking to the tracks without us...
Trying to get my buddies from NYC to join us as well, but I need an actual date to work with...
- Rob
Let me come play too! I'm very close to Island dragway, but I was thinking that since I have never made a pass at Atco Dragway, and the owner is thinking of selling/closing the track.. maybe I should get to Atco one day in the next few weeks and make some passes. Probably for a test and tune day/night.
Let me come play too! I'm very close to Island dragway, but I was thinking that since I have never made a pass at Atco Dragway, and the owner is thinking of selling/closing the track.. maybe I should get to Atco one day in the next few weeks and make some passes. Probably for a test and tune day/night.
We might be hitting island soon maybe even next weekend..
Wonder if I can buy a vette governor and try that out.
I have done a bunch of reading on this. Yes, start out with a governor that started out the closest to where you want to be, in most cases the Vette governor.
Those that have tried to make a low rpm governor achieve the correct higher rpm shift points had very limited success.
Only one on my phone, you can see the rest when we get to the track lol. You just need to buy a block off plate with AN fitting already in tact. Rest is very easy...
- Rob
This is the mechanical fuel pump mounting area, correct?
I have done a bunch of reading on this. Yes, start out with a governor that started out the closest to where you want to be, in most cases the Vette governor.
Those that have tried to make a low rpm governor achieve the correct higher rpm shift points had very limited success.
So what does a Corvette governor start rpm shift wise?
We might be hitting island soon maybe even next weekend..
gotcha. next weekend I plan on going to two car shows actually so I can't squeeze racing in that weekend. I know a few friends gong to each show and I told them I'd be going, so I don't want to back out from that.
Saturday is the car show in Mount Olive for their F.O.P. fundraiser
Sunday is a car show at Nielsen Dodge in East Hanover.
however, the following weekend, I have no shows to attend, so I can plan on hitting Island or Atco
At least, once you examine what you have at the moment ( and maybe your transmission guy installed a Vette governor) you can determine from that thread what it will take to move your shift points to where you want them. That's my take away from there anyway.
gotcha. next weekend I plan on going to two car shows actually so I can't squeeze racing in that weekend. I know a few friends gong to each show and I told them I'd be going, so I don't want to back out from that.
Saturday is the car show in Mount Olive for their F.O.P. fundraiser
Sunday is a car show at Nielsen Dodge in East Hanover.
however, the following weekend, I have no shows to attend, so I can plan on hitting Island or Atco
Ok cool keep me posted do you havyou Facebook page?
At least, once you examine what you have at the moment ( and maybe your transmission guy installed a Vette governor) you can determine from that thread what it will take to move your shift points to where you want them. That's my take away from there anyway.
I know he used alot of the upgraded sonovax parts in the trans
I just downloaded the holley software and a sd card reader so I'll be able to data log soon..so I'll know exactly what its shifting at very soon.
Let me come play too! I'm very close to Island dragway, but I was thinking that since I have never made a pass at Atco Dragway, and the owner is thinking of selling/closing the track.. maybe I should get to Atco one day in the next few weeks and make some passes. Probably for a test and tune day/night.
I met up with them yesterday, actually went there to check on his EBL P4 tune, and after a quick datalog he was already on the money. I guess he just needed a second set of eyes to be sure. He runs similar times to you so you guys would be a great matchup. His brother actually runs similar times to Gerard's wife, so that will be a great matchup as well. Off tomorrow, and more than likely will be meeting up with them again. Would like them to meet Gerard tomorrow if possible, and of course meet you when we get to the track, and maybe get a little 3rd gen thing going again in New Jersey. I have somewhat of a callout with some friends from NYC, which is why I need a date because it is a two hour drive for them from Queens. Called out the White Nova in the video below, low eleven second car. The S10 runs tens, but in this run he just finished installing the Sniper, and traction was just not there, and you can also hear it popping in the exhaust because he was tuning wot. Just a note for those watching the video, that sign was CGI, we were nowhere near Kennedy Airport, that sign was added for effect. We were actually somehow in Mexico that night....
This is the mechanical fuel pump mounting area, correct?
Yes, and when you run it to the valve cover, you don't have to weld the fitting to the side of the cover, either punch or drill a hole through the side of the valve cover, and bolt the fitting in with washers. Just use a generous amount of Loctite to secure it the same way you would with any oil pump pickup, or timing chain bolts. The further away the fitting is from the PCV the better, because it allows for any oil that was kicked up to fall out of suspension...
Ok cool keep me posted do you havyou Facebook page?
nah, I never had facebook. I just do email, phone, and a very few car forums. you can PM (private message) me on here, or I can give you my email/phone contact info in a PM
I just checked Islands website and they changed all the events this weekend over to be Test and Tune events. unfortunately I can't go this weekend or next weekend
Ok got the software downloaded to my laptop ordered the sd card reader now to go data log and see what this is truly shifting at..unfortunately its raining here so no test rides.. I really been wondering if this truly can do a high 11 pass im.told no that's all the car has In it..I feel it has a little more. What do you guys think?
I really been wondering if this truly can do a high 11 pass im.told no that's all the car has In it..I feel it has a little more. What do you guys think?
Oh.... My.... George. We're going to start that again?
Oh.... My.... George. We're going to start that again?
Well I was told 1 it barely has 300 hp 2 it would never go low 12s 3 it would not 60ft good so were excited that it did all 3 pretty decent.. I'm correcting a few issues and figuring out data logging so I can fix any other issues that come up.. Sorry for being excited to see if a low budget old fashioned build might actually get into the 11s all motor..in a full weight car...
No doubt you can. Just need more data to work with. Tune and tire and adjust shifts. That plus nov air with deep negative density altitude can help
Agreed the few things were trying next time out is shifting...data logging and I'm having her go thru the water box to heat the tires she didnt Last outing were giving the nittos one more try they dont hook I have the MTs on deck..lol also I fixed the pcv issue went with a catch can. I'm bringing the other cold air intake pipe so I'll be trying different things..wish us luck..
Yep that guy takes pretty good pictures. I would suggest supporting his business by buying some photos in the future.
I know that you keep saying that the nitto radials you have on there don’t hook but I’m gonna have to disagree with you a little bit on that. If you’re getting a 1.6x and 1.7x sixty foot they are doing somewhat well. It’s not like you are frying them on the line and for 100 feet. If so your sixty foots would be much worse.
09-23-2020, 06:23 PM
