MAF calibration first or VE table???

[roughneck427]

Hi i have a 2000 LS1 Trans AM heads and cam car. I had a guy tune it and its not been right and desire to get it right. It did 381 rwhp and 381 rwtq with a very small cam 216/224 .551 .551 115lsa cam ported 241 heads LS6 intake slp lid 42 lb injectors 80 mm throttle body and mac mids. I figure it should do over 400 at the wheels Now the person i bought the car from descreened the MAF and ported the ends which i dont know if i should go back to stock MAF or tune this one in. I compared the tune maf to a stock one and it hasnt been changed. So i know there is something there
My ltft are hanging around -5%-6% all the time here is a copy of my current tune and a copy of the auto tap data log i have any help appreciated. i do have a wideband i can try and do a mxscan datalog with but havent got that all dialed in yet as far as hook up. On the dyno @ wot a/f was around 12.7 i know this will all be out the window once the ve and maf are correct. i know the low oct and high oct spark maps didnt match and was going to cut and paste them what factor plays on what table the pcm uses for this. Thanks!!!


Chris

[n0dih]

Are you 100% confident on the fuel press reg? It doesn't take much of a leak to mess up fuel trims.

If so, you can change the fuel injector size to slightly larger and it will bring the fuel trims in line.

Were the injector flow rate(s) set properly to begin with? If to low, this would show this very condition.

Oh, I can't open your autotap file properly, can you email your config file from AutoTap? I have AutoTap 3.1 so once have that I can look at the logs.

[roughneck427]

well i looked at it they were set exactly to 42 lb injectors so thanks im gonna have to fix that checked my F/P and was 62 psi. anyone have a spreadsheet???

[hquick]

Try this!

[roughneck427]

Hey thanks for the sheet put in the info im just gonna start from scratch the last person to tune this car has done so much screwy stuff i just want to know what ive done so im not chasing my tail thanks guys!!! I did change the injector flow rate but the car ran even more rich

[roughneck427]

ok heres the stock tune i put a 85mm zo6 maf on it i inserted the table for the maf on a 01 zo6 for a starting point inserted the correct values for the svo 42 lb injectors. Now i can start my ltft were hanging around 18-20% with a flat spot around 2500rpm heres a copy of the tune and a csv file of the datalog thanks for any help. I know it says 01ta and 00ta on the other attachments im running a 01 pcm and a 01 cal file in a 00 car

Chris