This past weekend I was experimenting with Tunercat. The car has an annoying surge at cruising throttle, was bogged down off the line (I think it was going lean based on my ), and had some knock at wot, etc. It ran okay, but not good enough. If anybody would like to take a look at my logs and/or bin files I would appreciate it. Just volunteer and I will email them.

Any tips on tuning the car would be greatly appreciated. I want to get it as close as possible then go buy some dynotime with a wideband and get it perfect. The program on it right now is a pcmforless base with a halfass dyno tune on it. The driveability is crap and performance is not optimal by any means but it's not horrible either.

This is what I know about the car, keep in mind it's a 96 m6 with OBDI:

1) The cam is a 227/239 .560/.577 115 lsa. It idles around 50-55 kPa. Decelerating it gets 20-25 kPa. What tables should I alter and how should I alter them. How do the specs of the cam like duration, lift and lsa affect tuning. What I figured was that the open loop afr should be richened a little bit especially when cold, and the timing should be pulled back a little bit in the low-mid range, with 26* at wot from 4000 and on. Is that somewhat correct???

2) The car has a Vortech s-trim making 6 psi, not inter/after cooled, but with alcohol injection (I have been tuning with little or no alcohol running for the sake of eliminating variables, should I tune with it running?). How does this affect tuning. As I stated above, the timing from 95-100 kPa on the extended spark advance table in tunercat from 4000 rpm and up is already at 26*. What else needs to be done? Is it better to add fuel in the WOT table or in the VE tables? How do you know what to enter in the tunercat WOT tables???

3) These are the rest of the relevant mods:
-Lucas 36# injectors (I set the constant to 36.00 but I don't know if that's exactly correct).
-!EGR, !AIR
-Delteq

I think that's everything that would affect the tune. Thanks in advance.

 

(off topic, your PM inbox is full been trying to message you back)

 

try adding some spark advance in the surging areas. Also run in open loop with your camshaft.if your getting knock counts at wot your either lean or to much spark advance. And yes tune the WOT area in boost with the alcohol injection on. Not adding a variable.

 

I was considering going to an open loop tune. I don't think the stock PCM was ever meant to do any of the things we ask of it. I will do a search but are there any good guides or threads about open loop tuning?