on a tune from preditor

**ledesma54** · 04-01-2008, 02:18 PM

Has anyone been able to do a custom tune on there diablo for a 04 gto with heads and a 85mm airflow sensor and a cold air intake, just wondering and if you can share it with me that would be great, i cant get my long terms lower then -5 -6 range .

**The Silver Goat** · 04-01-2008, 02:59 PM

What's your injector slope set to?

**ledesma54** · 04-02-2008, 11:52 AM

Theres like -3

**The Silver Goat** · 04-02-2008, 03:38 PM

Adjust to -5 or -6 and drive for about 20 minutes and then read your LTFT's.
Adjust as necessary, I like to run at -2 to 0. I feel better knowing the PCM is reducing the fuel a touch rather than adding...

**ledesma54** · 04-03-2008, 02:03 PM

Hey silver can you send me your tune iam trying to get a more aggressive tune but thanks for the info

**The Silver Goat** · 04-04-2008, 01:05 AM

Injector Slope -14%

WOT Spark Advance
2K-4K +10%
4K-7K +6% to +8%

WOT Fuel Mixture
2K-4K +1% - these were set higher, as much as 10%
4K-7K +1%

I will be keeping an eye on these as weather warms just to make sure I don't get lean.

5% on timing is supposed to equate 1 degree.
This year I've been tinkering with it again. I've had the sled out and the LTFT are -1%. Last year I'd up the fuel and advance the spark without any method to my madness. This year I've re-set both to '0', incrementally advance the spark and not added fuel while monitoring the knock. I was looking at my exhaust tips and there a bit black so I've cut back the fuel.

It takes about 20-30 minutes to let the PCM adjust to new settings.
Then start with advancing the timing.

(I was just reviewing the Diablo web site and found some interesting information.
If I read it correctly once you have the LTFT set, which creates a lot of debate on another site, you can advance the timing without screwing around WOT fuel. The PCM handles the rest)
I've advanced the timing - reduced the WOT from original settings above. I attempted to monitor my Mv's, a lot traffic... They're supposed to be between 85X and 92X which is supposed to indicate a indicate a good A/F ratio. I'd reduced WOT to +3% and it's the first time I'd gotten close to ~87X. Below 87X is rich and above 95X is lean.

I have an M6 so I do not have any settings for A-trans. There's a couple of threads below and one of them has those settngs.

I've removed a portions of my MAF screen. On each side of the sensors - based on my past experience it's important to maintain smooth air over the sensors to hold an idle. Given the tube for my K & N is smooth I will be incrementally reducing the screen. The old tube is flexible and disrupted air flow. That's why my slope is set so high...

**LS2Tuner** · 04-05-2008, 12:59 PM

Originally Posted by ledesma54

Theres like -3

Yeah you just need to increase that a few more like -6 to -8. Depending on your heads though I would be willing to beat your end up more than that.

**ledesma54** · 04-05-2008, 03:50 PM

If i go past 8 or so ill throw the engine light saying that iam running rich, also were do you want your long trims and short trims to be and what speed do you go by when you check them.

**LS2Tuner** · 04-05-2008, 03:59 PM

Originally Posted by ledesma54

If i go past 8 or so ill throw the engine light saying that iam running rich, also were do you want your long trims and short trims to be and what speed do you go by when you check them.

You need to get on the freeway and put the cruise on for at least 10 miles before you begin to data log it. Then what I would do is get off on a exit where you can basically make a quarter mile pass getting right back on the freeway. Keep in in fifth because you want it at at least 2000 rpm with the cruise engaged for a while they should begin to steady out. Try to get the LT to stay 1 to -1 round about. And no they won't be dead even. But your looking for them to stay around 0 which won't happen either.

Good Luck

**The Silver Goat** · 04-06-2008, 02:43 AM

Originally Posted by ledesma54

If i go past 8 or so ill throw the engine light saying that iam running rich, also were do you want your long trims and short trims to be and what speed do you go by when you check them.

No - the diablo is telling you how much the pcm is adding or reducing fuel.
Don't be concerned with STFT's. If LTFT's are between -5% & +5% you are meeting the parameters of the software. The closer you get to 0% the better...

I had read somewhere STFT's are compiled to represent LTFT's, but I (in my opinion) beleive it's showing what the pcm is managing at that moment while LTFT's are the overall performance of the motor.