Just so everyone knows the background...
The OP's car had perfect looking datalogs. Air flow was showing that of a car making 475+RWHP, the timing was showing spot on whatever we commanded (and we've tried between 16-24 degrees at WOT) on 93 octane. The air/fuel was verified using different widebands/sensors/etc. and we've verified it's also what we're commanding. We've tried everything from 11.5-12.3. The car just wouldn't make power. It was getting roughly 9PSI and the car will not make power. We had ONE run where it made power on the dyno, but something still wasn't right. This was with John Spruill, the engineer from TECHCO here in-house in Aston, PA tuning the car. Once it made power, we were happy with the results, and John from Techco went on his way. He was here because this was one of the first units, and they wanted to test results in the field. The original poster called us with results, and claimed "some days it runs its ass off, and some days it feels like crap". He had some weird check engine lights coming on, and other odd sypmtoms. We had him come back, and ran it again on the TECHCO tune and it only made a consistent 390-410 RWHP with the same exact tune it made 465RWHP on.
Compression/leakdown test results were great, as expected because the car had only 30,000 miles or so on it. So I said, okay let me retune this thing from scratch, using SCT software. So I set him up on the dyno and tuned it to find that the car still was only making roughly 390-410RWHP whether or not I tuned super aggresive or super conservative. All of the odd symptoms and check engine lights went away with our tuning, and the car felt more smooth but it still wasn't making the power.
In the mean time, we tried new coils, 4 sets of plugs, and numerous amounts of datalogging and retuning with different VCT maps, timing maps, etc. etc. Finally, we realized something in the PCM or ignition system had to be holding the car back. How can the car make the same amount of power with or without the gap being open or closed from 45 down to 30 with no other symptoms, blowout, etc. Just because the PID shows the car getting 18 degrees of timing at the PCM, doesn't mean that we're actually seeing it, it's just a vehicle PID.
At this point I think we have a weird voltage issue, pcm issue, or a problem in the harness. The customer wanted to try a boost a spark. Even if this worked and fixes the problem, the underlying issue is still there. It could just be enough of a jump in voltage to fix whatever he had going on in the mean time.
To make this clear, on every supercharged application for our S197 platform, it is recommended to change to a colder plug and gap them accordingly! He isn't making "more power" with the gap open, and that's not why we're running them that way. We were experimenting with the plug gap differences during our ignition problem hunting. Techco's original tune file set off misfire codes, and low ignition voltage codes which is where we started until we retuned and the codes went away.
When the customer brings us the car this time, we will gap the plugs back down at 30 and see what it makes for power. Again, I would much rather the car get dropped of so that we can route through the harness, and assess the PCM for voltage drop issues.
Chris Rose
Tillman Speed Inc.