Unplugged the MAF and did some logging

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Oct 4, 2004 | 02:04 PM

CHRISPY

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Unplugged the MAF and did some logging

Well my cruise LTRIMS are -11 to -14

WOT LTRIMS are 0 and -2

Part throttle (say half throttle) LTRIMS are +4 to +5

I have stock MAF, 37# Delphi injectors, 98 PCM and a six speed

Someone PLEASE help me get this crap straightened out.

Motor is 385ci with 236/242 cam on 110LSA, 11.8:1 comp, running 1 3/4 to 1 7/8th longtubes with cats.

I have a bad stumble on tip in seems to clear up after 3000rpm.

If someone could give me the stock 98 VE table values that would be great.

Also if you have 37# delphi injectors and have a 98 PCM your injector scaling values would be great too. Actually I would like to see a stock 98 IFR table as well.

Also what is the best way to hit all cells? I am using ls1edit at a tuners dyno but will be buying HP tuners soon. part throttle up to redline through several gears?

I want to nail closed loop tuning. WOT is ok for now but as I dial in part throttle I'll undoubtedly need to make WOT changes as well.

Oct 4, 2004 | 03:04 PM

deezel

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From: Dallas

Stock '98 files are available on the web, just look. There is probably one in the HPT .bin repository at the top of this forum. Just rename to .ls1 and read it with your software.

37# injectors should have a flow rate around 4.5 g/sec.

Oct 4, 2004 | 03:41 PM

HumpinSS

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From: Waldorf, MD

Your cruise trims need to be leaned out some and the part throttle needs to richened up are you using the HPTuner the percentage that you are off in yout LTrims histogram you can take that right back to the ve table and richen up or lean out the mixture. dont forget to reset your fuel trims after a flash

Oct 4, 2004 | 04:32 PM

Another_User

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Your stock 98 table won't be worth a crap for tuning from if you have a cam. Even the Z06 table isn't much help.

Oct 4, 2004 | 04:59 PM

CHRISPY

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Quote:

Originally Posted by HumpinSS

Thanks guys

I wanted to see the stock values to compare.

I'll be using LS1edit at first and then HP tuners.

When you say reset the LTRIMS after a flash what exactly do you mean?

Has anyone used ChrisB's injector scaling spreadsheet with much success?

I used his spreadsheet to calculate the correct values for the IFR table for my 37# injectors but they seemed to make things a lot leaner. The car felt "dead" as well. I richened the IFR by 10% up to 95kpa and the car picked up a ton of power and felt way better at part throttle.

I think I'll go back to the IFR values I had originally from his spreadsheet, drive around with the MAF unplugged, log everything, and then adjust using VE.

Then I'll hit the dyno for WOT AF.

I'll need to set the low octane table the same as the high octane table with the MAF unplugged right? Anything else I need to do besides unplugging the MAF? I need to get a smooth bellows as well I guess...

I REALLY need to get HPTuners and a freaking wideband.... when is that going to be available?

Oct 4, 2004 | 06:18 PM

HumpinSS

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From: Waldorf, MD

I would use HPTuners as it has al you need and there is no tabulating data for yourself. If you look at the HPTuners scanner you will see PCM/VCM control under that menu is where you will reset the trims.