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Discussion Starter · #1 ·
When talking to the Dyno shop guy he mentioned in their tuning they look at the SFT1 [Short term fuel] readings...Now I know that the articles, like http://www.stlclubgp.com/tech/afc20/ talk about tuning, with the AFC2, etc, to the LFT1's, which I've been doing...

Wouldn't tuning be more accurate, tuning to Short Term rather than Long term?...Just asking...
 

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When you go WOT the PCM locks in the last known LTFT. Having the LTFT right before going WOT will mean you get the best possible fueling for the dyno run.

Correct me if I'm wrong guys....
 

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Discussion Starter · #3 ·
That's what I try to do Todd...but it seems that no matter what my LFT's are while staging...can be a low +, or even low -, they seem to jump to a much higher +, running lean, at WOT for the run...This is with 8-11 settings at 100--103 to see no KR, O2's alway seem to be in the 980+ thru to 940 range during the run...
 

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I normally get the car baselined for the street first. At the track I adjust only for highest trap speed. If it knocks at the track, but it's faster I don't care. I've pulled 3 tenths out of the car at the track over optimal street settings, car's always happiest for me with about 2-3 KR; go figure...I don't even bring the a-tap to the track anymore, it just gives me too much to think about. I usually start my runs by leaning out the car across the board 1% at a time until trpa speeds peak, then start to fall off. Then I bring it back up 2% across the board for a margin of error. For instance, last time at Cordova my first run was at 101 mph, after leaning it out 3% my traps were 104.
 

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Q on LTFT's.
At cruze dosn't the EVAP affected them, from it venting? And also dose a vavle cover breather affect the FT's (short/long).

Ever sense my LS1 TB that blocks the PVC passage. And I used a vavle cover breather to vent my crank pressures. I havn't been able to contraol my LTFTS (miniACF v2) But useing the STFT still adjust fine to +/- 3 after tuning.

And has anyone drilled a hole in the ZZP LS1 TB adp.plate to pass air thu the PCV passage like stock dose? Where dose the PCV passage (lower right corner) of the M90 inlet have to get a singal from. (were dose the passage enter the main inlet) I'm not sure if it's ahead or behind the TB blade?

Also my rear block plate has a oil leak that got worse with the vavlecover berather. I want to have the PVC system working again, I think it will help for oil leaks.
 

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It gets it's signal from before the throttle blade.
 

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Nope, but the TB's are all esentially the same in most respects. I have a '97 L67 TB with a thinned shaft, 72.5mm bore, MAF post removed, Fully epoxied transition, and a LS1 MAF. I'm building a 75mm TB right now that bolts on with no adapter plate by bastardizing a junk L67 TB, and mating it to a L32 TB. It's not for my car, I just wanted to do it;to say that I did.
 
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