LTrims stick at +25% almost all the time
#1
LTrims stick at +25% almost all the time
I was driving around doing some logging and 90% of the time im cruising around, my ltrims stay at 25%. I know my car is horribly tuned and i believe i may have my injector flow rates a hair off. Could this be the cause???
Ltrims stay at 25% and i swear @ WOT timing never goes above 19-21 degrees....
Ltrims stay at 25% and i swear @ WOT timing never goes above 19-21 degrees....
#2
Re: LTrims stick at +25% almost all the time
What mods have you done?? What are your injector flow rates and size of injectors. Did you recently have the intake off ,injectors out...air leak??? Give us a narrative....a little background/history of the motor and L Trims.
joel(Bink)
joel(Bink)
#3
Re: LTrims stick at +25% almost all the time
I have a 98 setup that had 28.8 factory. Now i have Accel 30lb (rated @ 44.1 psi) injectors in the car. Here is what i set the Injector flow rates to, are these wrong?
Id say no on any vacuum leaks, alot of it is just the problem of huge tuning issues getting the car right with being a ls1 conversion with these injectors. When i started the car made 340 rwhp on my dyno, then through random changes and trying to get problems worked out worked up to 380 rwhp...and now im having problems with the tuning again and the car is putting down 340-350 rwhp
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80
4.47 4.49 4.52 4.56 4.58 4.61 4.64 4.66 4.69 4.70 4.74 4.77 4.79 4.82 4.85 4.88 4.89
Oh im sorry didnt list mods....
ls1 conversion into older corvette.
All forged internals,Stage 2 CNC Heads, TR 227/230 Cam, LS6 intake,Th350 /w 3800 converter, Dana 44 rear /w 3.91 gear, Weld Prostars /w 28x13.5 ET Streets, Accel 30# injectors, Walbro GSS340, SLP 85MM MAF, 2-stage Dry/Wet N20 kit, 3100lb race weight, MAC headers /w custom 3" extended collectors, Dual 3" true dual h-pipe, 3" Moroso Spiral Flow Bullets dumped
Id say no on any vacuum leaks, alot of it is just the problem of huge tuning issues getting the car right with being a ls1 conversion with these injectors. When i started the car made 340 rwhp on my dyno, then through random changes and trying to get problems worked out worked up to 380 rwhp...and now im having problems with the tuning again and the car is putting down 340-350 rwhp
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80
4.47 4.49 4.52 4.56 4.58 4.61 4.64 4.66 4.69 4.70 4.74 4.77 4.79 4.82 4.85 4.88 4.89
Oh im sorry didnt list mods....
ls1 conversion into older corvette.
All forged internals,Stage 2 CNC Heads, TR 227/230 Cam, LS6 intake,Th350 /w 3800 converter, Dana 44 rear /w 3.91 gear, Weld Prostars /w 28x13.5 ET Streets, Accel 30# injectors, Walbro GSS340, SLP 85MM MAF, 2-stage Dry/Wet N20 kit, 3100lb race weight, MAC headers /w custom 3" extended collectors, Dual 3" true dual h-pipe, 3" Moroso Spiral Flow Bullets dumped
#4
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Re: LTrims stick at +25% almost all the time
You probably have a couple things contributing to your LTerms
1) SLP 85MM MAF
2) Injector Flow Rate Table
Your injector flow rate table really doesn't look that bad, but every setup is different.
A couple things you could try.
1) Try putting the stock MAF back on and see how your LTerms look. If the LTerms correct down to somthing normal, then you know how much your SLP MAF is scewing your air. You can then make the necessary corrections in LS1 Edit to your MAF table to get it to work right with your SLP MAF
2) Reduce your IFR table. Try shifting your injector flow rate table down in 10% steps (multiply by 90%) and see if the LTerms situation cleans up.
Good Luck,
Kevin
1) SLP 85MM MAF
2) Injector Flow Rate Table
Your injector flow rate table really doesn't look that bad, but every setup is different.
A couple things you could try.
1) Try putting the stock MAF back on and see how your LTerms look. If the LTerms correct down to somthing normal, then you know how much your SLP MAF is scewing your air. You can then make the necessary corrections in LS1 Edit to your MAF table to get it to work right with your SLP MAF
2) Reduce your IFR table. Try shifting your injector flow rate table down in 10% steps (multiply by 90%) and see if the LTerms situation cleans up.
Good Luck,
Kevin
#6
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Re: LTrims stick at +25% almost all the time
Before messing with the MAF table, you need to determine whether or not your high LTerms are being generated by your SLP MAF (in which case you will use your MAF table to correct for) or by incorrect numbers in your injector flow rate table (in which you don't want to mess with the Injector Flow Rate table and not the MAF table).
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Re: LTrims stick at +25% almost all the time
i had the same problem and it turned out to be that my MAF screen had a bunch of crap on it and i just blowed it out and blew off the sensors also and it fixed it
#9
Re: LTrims stick at +25% almost all the time
1. Sell the maf and install stock maf(rated to 550hp)
or
2. Install stock maf, tune injector flow rate and wot vs rpm tables to get your o2's in line. Now, re-install the ported maf, and get all specs back to where they were with the stock maf by adjusting your maf table. Hope this helps!
or
2. Install stock maf, tune injector flow rate and wot vs rpm tables to get your o2's in line. Now, re-install the ported maf, and get all specs back to where they were with the stock maf by adjusting your maf table. Hope this helps!
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Re: LTrims stick at +25% almost all the time
Are you getting any knock at those 19-20 degrees of timing. If not, then you should look at your total timing table for the low and high octane fuel map. Maybe that low octane map is set to 21 degrees total. My friend has the same ltrim problem that you do in his 98. I dialed in the high rpm range, but still working on the low speed ltrims. Will try the stock maf today. The 30 svo's and 85 mm maf need to be tuned around. I will post back if I solve it today.
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Re: LTrims stick at +25% almost all the time
I multipied 0-4500rpm IFR table by 74%, and I got the cruising ltrims to 2%. This is for a 98 car that went from 28.5 injectors to 36 lb/hr. Cars seems to respond much faster at part throttle.