Tbi-MAX

well everyone says WOT and see what happens well... i cant... the most i can get out of my 383 is about 41% TPS then it starts to hickup (basically PAUSES) then bogs down.... so most of the time i just light pedal to get to speeds i want to go its fine..

ive messed with WOT AFR, injector flow, AE tps, AE MAP, PE... PE made a HUGE difference, cause b4 it always back poped out the intake... for some reason it seems to want less AE MAP and tps... but i dont want to take out too much........

BLMS are 120-128 not lean and ening still will not WOT... also i have 0 knock counts.. so its not pulling timing..


i changed stioch to 14.5 and truck sounded better. but i keep going back to 1 tune i did that the truck loves..

what is a good stioch for a 383 runing 87 oct ? and what does a 383 WOT AFR table looks like? mines at 12.5 all accross the board..

12.3 didnt seem to help, and 12.7 didnt either... it must be 12.5 for it to run decent pull up to maybe 3k rpm. i never spined it that high or went pass 42% tps... i need help what to do next?

injector flow rate on my combo is set at 110 flow, and my fuel psi is right at 17.5-18

Tbi-MAX

more info:

383ci-6.3L L05/ 454 BBC TBI / 90# / VAFPR / MSD6AL / WIX 14x4 / Vortec Heads .520 lift/ 214/224 - .442/.465 - 112lsa / 4.030 -12cc dish / 3.75 stroke - 1piece / Walbro 255 / Moroso 6QT / Headman LT headers / 3" custom single exhaust / 7427 PCM with Ostrich

RBob

iTrader: (1)

Looks to be out of fuel. Have you checked the injector duty cycle and the AFR (in the exhaust, not the commanded)? Does the fuel pressure hold under load?


If you want to try something: increase the fuel pressure to 24 psi and adjust the BPC and AE tables accordingly. Then see how it is.

RBob.

Tbi-MAX

im going to set that fuel psi tonight... and adjust the flow rate of the 90#s. But your on to something... cause 1st when it was set to 15 psi, performance was lower..

it needs more fuel.. but what about idle? will i have to hook vac to vafpr?

ill post how it works...

also my wideband is installed, like almost 3wks now, and i havent pinned it to the pcm yet..

Tbi-MAX

hey Rbob. i set the fuel psi to about 24-25 range. and set my flow to 123.29 i belive. i took out maybe -250 map vs ae in all areas of the map. i used alot of map vs ae

ill tweak it more tomorrow. l will also post my log in a few mins once i sync the laptop. but OMG the new psi and flow woke the snot out of my combo. now it just feels like im on the strip, take a look at the log. i think i was was doing 72-74mph @ 12.95 tps of something like that... throttle response now is 100% better, and it wasnt bad b4.


so i think i can start messing with AE vs TPS now? to get to WOT??? or do i just WOT now and see what happens? b4 if i got moderately fast, and it bog i would let up.. but if i feel i could give more pedal i normally do.... i guess the question is should I just floor it flat out to the floor to TEST WOT? i guess thats what im trying to say...

im very impressed with the results, tmmorw i can test more.

Tbi-MAX

attached is my LOG FILE in .ADL format... just rename the extention... take the .txt off and leave the .adl

its the only way i can upload it. but it should work. let me know about the log...

its amazing how raising the fuel psi, made the BLMS more conistent like 126-128 all night last night. so i take it my fuel tables are good. b4 the blms would be 115-128, and at idle 93 ish... now i sat at idle at 124 last night.

today ill mess with things some more.

RBob

iTrader: (1)

Tbi-MAX, I wouldn't go out and just floor it to test WOT. You need to crowd it a little and then check the injector duty cycle and exhaust AFR.

Then if it is OK you can take the RPMs up a little further. Otherwise it may be time for more fuel pressure or higher VE%.

What you need to be careful of is: starting to add fuel, having the engine start making power, but having it still on the side of too lean. You need to go from the previous way-too-lean to the rich side and while skipping the middle.

its amazing how raising the fuel psi, made the BLMS more conistent like 126-128 all night last night. so i take it my fuel tables are good. b4 the blms would be 115-128, and at idle 93 ish... now i sat at idle at 124 last night.

This is a sign that the fuel pressure was not under control. It was high at idle (low fuel demand) and the pressure dropped off as the demand increased.

This is caused by the large pump and marginal return system (regulator, return line, injector pod passages).

When you increased the fuel pressure two things happened: the volume of fuel that the pump is moving is less, and the back-pressure from the return system has less affect in changing in fuel pressure. So now the fuel pressure is more consistent over the range of fuel demand.

it needs more fuel.. but what about idle? will i have to hook vac to vafpr?

You can only use a VRFPR if the ECM code is set up for it. No stock GM code has that feature for TBI systems.

RBob.

Tbi-MAX

well its time to drop the tank again... all 42 gallons of it... the 24-25psi i set last night was good today also, then i added about 23 gallons to the tank, and now the fuel psi under the hood is about 12 psi. it also drops off instantly. also i witness the regulator double click twice and watch the psi drop and climb back up for a sec.

maybe my hoses blew off the walbaro again? but i have steel clamps this time instead of plastic. but im going to put a vortec pump in there just to see if its better.

Tbi-MAX

well the hose from the pump to the sender in the tank had a nice long slit in it, where it busted the plastic clamps hold, but i still replaced em with metal, along with some new fuel hose. the old hose looked like vaccum rubber.

psi is now strong as can be. when i give it throttle now, it just stays solid, infact it trys to raise about .5

so thats a big difference. this walbaro 255 just is too powerful for its own good.

i droped my fuel psi back to 20 psi now. and truck runs great and strong, also i just started a new tune again. setting VE currently, going to WOT to get the VE right, b4 i start with my new timing table, and then start with PE

ill keep the progress posted

Tbi-MAX

ok so at 4K rpm i keep hitting a WALL.. feels like its out of breathe literally.. from the log the blms were way high, but from what i understand the BLMS are not set to learn that high of a rpm in my .bin

now my WOT to AFR starts off at 13 tappers to 12.7 around 2400 rpm and now 4000 rpm i have a new setting of 12.5

easy throttle and cruise is good

quick, moderate, fast throttle, and WOT it wants to pause...

what now?

runing 20 psi with injector flow at 116.19 or something like that.
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my SA looks like this


also this is what i can do with under 13% tps... if only i can get to use 40-WOT TPS! i LOVE my intake.

flat run


more load going uphill

Ronny

iTrader: (1)

Injector Duty Cycle ?

HaulnA$$

Its not the Walbro 255, its the hose. You need to use the hose that comes with the Walbro installation kit or equivalent "Fuel Injection" hose that is rated for in-tank use and high pressure. The stock TBI hose is not strong enough as you painfully figured out and neither is standard fuel hose. This happens a lot. You should re-check your tune after the hose is fixed.

From the autoperformanceengineering.com website:HTH

Tbi-MAX

how do i do this? i tryed to figure it out.. but i think its injector or 02 related..

rpms flux maybe 2-400 at times...

my wb02 is hookedup now and i got 12.1 somettime 11 @ idle... driving under 2500 i get about 14 and 13.... and when i shift gears, its seems to lean spike.
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thanks for the info, yea, it was the hose fault.. it turned into mush... amazing what the pressure can do. thanks for the advice.

RBob

iTrader: (1)

Injector duty cycle is based on the engine RPM, injector firing rate, and the commanded injector PW. For a TBI setup:

RPM / 60 = RPMSeconds

With each injector firing twice per revolution, multiply by 2 and invert for time. Multiply by 1000 to convert from seconds to milli-seconds:

(1 / (RPS * 2)) * 1000 = available injector time in milli-seconds

Then:

(PW / Available time) * 100 = DC%

Example:

6000 RPM / 60 = 100 RPS

(1 / (100 * 2)) * 1000 = available injector time in milli-seconds

= 5 msec of available time

If the PW is 4 msec:

(4 / 5) * 100 = DC% = 80%, which is OK (anything under 85%)


Example at 4,000 RPM:

4000 RPM / 60 = 66.67 RPS

(1 / (66.67 * 2)) * 1000 = 7.5 msec

If the PW is 7 msec:

(7 / 7.5) * 100 = DC% = 93%, which is not good


RBob.

Ronny

iTrader: (1)

I see you use TP-RT. Does not that show DC in logs? I thought for sure it did.

pandin

Why is it that a stock (bua) Memcal table shows a max of 9.4 ms, 256 load, at 6000 and 6400 rpm, this does not include the PE.

RBob

iTrader: (1)

Injector duty cycle is based on the engine RPM, injector firing rate, and the commanded injector PW. For a TBI setup:

Bolded the reason, HTH's.

RBob.

Tbi-MAX

hmmm, all i have is the injector.xls file, the new version. now im runing 25 psi of fuel on 90# injs in the BBC tb, on my hurricane intake highrise manifold...

listen its set at 129.9 flow i caluclated. it actually runs awesome man, atleast im getting to 46% tps, so it does lots better, and moves faster, i mean thats all it will take to do max speed. but i want to flat out go 100% tps.. i want to WOT!

how it is now, it hits lots less wall! ive still been playing with VE. I noticed I was runing a weak VE, and was feeding via AE.. now im runing 250+ more than a stock bjym bin for SBC pumpshot.. with the same AE vs MAP. and it accells amazingly faster!

i also read the more psi the less AE needed, so i gave that a try and it runs tons better, with the fatter VE.

also noticed that i was hitting walls with both sbc and bbc injs.. but when i made the map cells say 80,90,100 the same map number... then the walls disappeared... so i tried it with the bbc injs, and well lets say im keeping these in for good, but got to work on VE, and populating it properly.

so i take it my combo wants a steady stream of fuel? not constantly changing per map? cause it accells tons faster like that too.

does my VE has to be curved? or can it peak like a stair case?

the peak VE i was using is the VE with the same map numbers in certain cells. but the engine loves it... the curve VE i was using felt awfull.. couldnt flatten the map cells, cause that would make the VE stair step...

im also run tons less PE, which make tps feel better and get better mpg.

as of now this is the best its ran.

is it a proper way to populate VE? and i still cant WOT..

Tbi-MAX

also may i add, im runing in OL as well.. tons better..

here is what my SA table looks like.



and here is my VE... but i took out more fuel, a little, seems to run better. my WB02 is not working, and waiting on Moates to call me back.

but last i read it was rich. about 12-13s.



ill upload my latest screenshots today.

Fast355

iTrader: (2)

TBI-Max, I just thought I would let you in on my latest timing table. I happens to be the stock GM Minimum Best Timing (MBT) table from a factory 1998 G1500 Vortec engine. All I can say is that it HUALS *** running this timing table, doesn't detonate at all, and is getting 21 mpg highway from my 305. No matter what speed I am doing, I can nudge the gas a little and it will pick up in OD no less.

DM91RS

Chris...it would be interesting to see the numbers for that chart.

Tbi-MAX

dittos...

Chris post the numbers please...
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hmm isnt your van heavier than my burban? i would appreciate that type of mpg now.. its like im stuck 12 mpg all over, hwy or city.. wb is always rich, but trying to get the VE inline..

do u think my SA maybe hindering my WOT? my current SA table is nice, i mean it responds good, and makes me feel like im in a car.

Fast355

iTrader: (2)

DONE

I honestly believe that your Suburban out-weighs my older G-series van but not by much.

Running rich can hinder gas mileage and WOT power.

SA can definately hinder WOT just drive a NBS with lots of torque management and you will see what I mean. My L31 has so much torque management that it struggles off the line and through 1st gear. 2nd gear pulls much harder than 1st.

DM91RS

Cool.....thanks....DM

Tbi-MAX

what do you think is my problem then? i mean when it acts shaky, i just let off. i just want to WOT. but i think it may have to do with my async, snync parameters in my bin. also i notice BBC VE tables peak in the middle map, and tapper off on the ends. currently my VE peaks at the higher map areas.. 70-100

care to take a look at my bin?

Ronny

iTrader: (1)

90 lbs injectors with 30 lbs FP seems like a ton of fuel being delivered. granted it is a 383 CID! what are the BLMs looking like in datalogs? How did you determine 30 lbs for fuel pressure?

I have 80's at 19 lbs and that is adequate for my 350CID at 5800 rpms for A/F. I wonder if your AE event is drowning engine in fuel?. My log this morning a a fully heat soaked manifold showed excessive AE fuel. Getting much warmer here in WI past 2 weeks. So I am pulling about 15% out of TPS-AE today as I am getting much better fuel distribution in manifold I believe.

Tbi-MAX

no blms they are locked at 128. again im in OPEN LOOP. im thinking bout trying CL again. ive ran as low as 15 psi b4. and as high as 30 psi. all produced the wall in the same area. both bbc and sbc injecs. my manifold is a high rise single plane intake. with huge runners.

do i need to use LESS AE than a stock sbc bin bjym?

to be honest im going to drop the psi back down to 20 psi, and start over on the tune. but yea, i have a vafpr with gauge.

Fast355

iTrader: (2)

I would honestly drop the pressure down to about 16-18 psi and start fresh. Too much fuel can bog the engine over just as quickly if not quicker than too little. Usually too lean will give a pop back out of the TBI as you roll on the throttle and too rich will emit a grey smoke screen from the pipes.

Tbi-MAX

ok, im going to revert back to 18 psi, and see how it works with the new tune. ill keep you posted

pandin

As a "tuning aid" set the BLM's to 130 max 125 min, you can see what direction the Closed loop tune is heading with out the over rich/leaning your motor. This is a way to work the closed loop to the open loop in smaller steps.

I use 140 int and 130 blm to watch when the tune goes lean from rich, if I use the "stock" 180 int and 160 blm the injector pulses would rise from 4 msec at 70 mph to 12 msec and the motor would just be drowning in fuel.

If you are locked at 128 you have no way of knowing which direction the closed loop is adjusting the AFR.

89RsPower!

I'm curious what type of vehicle is this in? Never heard of something with a fuel tank that large.. some sort of truck with multiple tanks or something?

Fast355

iTrader: (2)

He has a 95 suburban. My G20 Van has an aftermarket tank in it that is 43 gallons. Bought it a few years ago from JC Whitney.

Ronny

iTrader: (1)

YIKES! Do the math $4.29/ gal X 43 = $184.47 Fill er up and check the oil!
Thats 87 octane this morning at Speedway. I filled up with 89 last week and seeing 1000+KC on moderate acceleration. when I burn 93 octane seems to not trigger the sensor. So I need to spend like $4.49/gal.

pandin

What about lowering your timing when you 87 octane, stock engines run more timing then "Hot Rod".

I run 87 with 10:1 (aluminum heads) 40 degrees max timing, you need two chips one for DD and one for GO FASTER.

Ronny

iTrader: (1)

yes am aware. last year 2007 no issues on 89 octane. I pulled timing in 2006 till there were no KC's. this year i see KC. Maybe 89 octane is not 89 but 87 and I am getting ripped off. I will run 93 and check that. SA main table is max timing at 36 dropping to 24 at 95 MAP(WOT). I see no PE adder table in TP? PE tables I see are all zero'd out.
64 cc aluminum heads/10.0/1 with -6cc pistons.
Sorry for the hijack.

Fast355

iTrader: (2)

Mines only 3.29 X 43 because I am running on E85. It is still $141.00 though. I get 17-19 MPG running on E85. I go 700+ miles on one tank and only drive 30 miles a day. I fuel up about once a month. I was able to really crank up the timing (very octane limited with 10.5:1 compression on 87 octane E10) while running on E85 (100+ octane) which helped compensate for its over 50% BTU loss for every gallon. Takes 1.56 gallons of E85 to get the same heat energy as gasoline, but the engine runs more efficiently when its not octane limited by 87. 93 octane gas is well over $4.00 a gallon here. It feels like I have an additional 30 HP/40-50 TQ running on E85 with the advanced timing.

Ronny

iTrader: (1)

Major hi-jack here by me ! I just posted on "alternative port intakes" my future plan to go Victor Jr with my modded EBL and run E85 with appropriate FP and injectors. Might happen next spring.

pandin

What bin type and ads file are you using, I could only read some of the columns?

pandin

To give you a compare, the stock tune with 24# injectors running 50# fuel pressure, liked 23# in the injector constant, the same as the stock 22# at 43#. The Maf was reading low(187 grs/sec @ wot) which leaned the tune.

I have issues with the O2 mv going to 0 mv at idle (way high blm's), after installing a true dual exhaust. The "stock" 2-1-2 no cat system ran, 158 idle blm's and 128 at cruise, and the freer flowing, true dual, no cat system was beyond what the ECM could adjust for. Even more so with a repaired calibrated MAF (240 grs/sec @ wot).

When I lowered the O2 swing points it still ran better at less than the calculated injector constant of 25#-27#. I had to lower O2 swings to .300 V mean to get the BLM's to drop below 128 @ cruise (2000 rpm @ 70 MPH).

Each engine combo has it's own non normal quirks.

Tbi-MAX

OMG FINALLY!!

im so happy, WOT on the stroker is outrageous....

my flowrate was wrong, and was calculated differently..

now engine is happy, alot of tps vs ae was cut as well, i needed less than stock l05!

i mean it chirps on comand now... now i have to get my wb02 working, needs a new sensor. then i can fine tweak it...

psi was lowered to 16-17 psi, and tune was re calibrated. hands down, this thing moves like a toy car.

pandin the bin and ads file i can send you, but that data is old. i can send my current bin/xdf if you want to take a look.

my next stop since i can finaly now WOT is to get my mpg in good order, and try to make this thing daily drivable.

Tbi-MAX

pandin

So what is your "MPG" in the video?

How about your "SPG" ?

Tbi-MAX

well actually the truck mpg went up!! im still so much impressed with the tune im runing now... i mean i drive harder, VERY HARD, then it gets same or better gas mileage than when it was slow and slugish! no black smoke out the tail pipe no more. PART throttle is so responsive and crisp in this truck, its like not a truck.


that video, and these others i did the same day, i had a 1/2 tank of gas... at the end of the day all that hard driving, i was still between 1/4 - 1/2 tank for all those pulls... so yea, thank GOD i kept it fuel injection...

tell me what you think of these, video, excuse my tires, i have a set of 33s in my kitchen waiting on my black 17" rims..

this video, im really far as hell from the stop sign, when i turned out, but it gives a sense how fast this big thing moves. i pretty much let off the pedal twice on this


then this video, i got alot of hate on FSC, cause its alot of haters over there... for the 1 wheel peel, its a stock g80 locker, that needs to be changed to a trutrac. yet still i still put down 2 strips of rubber, you can see some in the video, but i should have took pics of the lot. my gears are still stock 3.73. i was told when i put my 4.56s and 33s, ill have even more power.



again the truck is not fully tuned, i still think im rich at 1st tip in these video, its still alot more hidden power... i just got it close enuff to wot.

va454ss

iTrader: (1)

You're having way too much fun

Tbi-MAX

so now that i can near wot/wot, what should i start doing now? whats the proper steps to make sure everythings is in order? i know i want to adjust my min air at idle for my current fp of 16-17. and then get the idle down to about 550 rpm, i know ive have id at 500 b4. now its like 690 or so.

i have a slight bog at 1st tip in, then it pulls like crazy. im runing in CL, i dont know if thats why mpg is up.. i really love my part throttle, im actually runing slightly more than b4 and its awesome for 93 oct.

basically just idle i want to adjust, and fine tune WOT! also i want to get mpg into the mix as well, so i need to know like a order to follow or something as i go along.

pandin

Just to give the difference in the effective drive ratio (tire size and rear gear ratio).

My vette
255 50 16 tires 26" and 3.07 rear gear = 2000 rpm 72 mph (Factory "performance" rg).
26" and 3.55 rg = 2000 rpm and 62 mph
26" and 4.11 rg = 2000 rpm and 54 mph
26" and 2.56 rg = 2000 rpm and 85 mph ("economy" rg)

Your truck with
33" and 3.73 rg = 2000 rpm and 75 mph
33" and 4.11 rg = 2000 rpm and 68 mph
33" and 4.56 rg = 2000 rpm and 61 mph

235 75 15 = 29"
29" and 3.73 rg = 2000 rpm and 66 mph

Notice how close the 33/4.56 is to the 26/3.55 which is a "street" gear, with no extra for the added weight.

The pick of tires and rear gear will make a difference in how the TPI is tuned.

Also remember anything past wheel spin is not used.
500 ft# motor + 400 ft# tire = 400 ft# vehicle.

Fast355

iTrader: (2)

Actually it IS used, just not in first gear.

pandin

One way to tune

Idle first - open loop/closed loop.

Part throttle/cruise - closed loop (adjust blm window to cover from interstate cruise and down, for mpg).

3/4 throttle - closed loop (over 3rd blm cell boundary rpm and gr/sec) and Accelleration Enrichment, tune for max power.

WOT - (blm cell 15) and Power Enrichment,tune for max power.

do fuel then spark then repeat.