JakenBake

What's up guys, so yesterday while cruising around I ran into a little issue when I was heading back home. I'll start by telling my setup. I have an 04 S2k with a stage 2 SOS kit with the largest pully "6in". I have the SOS street clutch kit, 4.57 gears. The car made 313WHP on a Dynojet. And it's tuned for 93 octane on an AEMv2 EMS. It also has a comptech differential housing.

Ok on to the problem, when hitting anything above around 4 1/2K the car seems to drop off it's power band. It doesn't feel like the clutch is slipping. The car is making a very very small backfire at times when shifting. I'm not sure what it could be... Perhaps bad gas? The car was tuned in the early winter at about 45-50 degrees and yesterday it was 80. The gas I put in was 93 Octane BUT it was from a 7 eleven. As always, thanks for any help!

cheddaboy

spark plugs maybe? I had a similar issue, at WOT my car would bog out.

s2000Junky

Wouldn't think you would be having any spark blow out issues at only 313whp, but if your plug gap is too large and your running really rich now due to a poor fuel tune for the new temp conditions, then its possible I suppose. What plugs you running and what's your gap? Do you have a wideband to monitor your afr? If not you should, its important. Same with a boost gauge. Your sc belt could be slipping bad and you would have no idea without boost target on your gauge. That can cause a major power drop, and will usually mess with your fuel tuning calibration, so its compounded.

JakenBake

Ok, it's been colder out and the car is running perfect. It must be the tune acting up in warmer weather,

AP1EM1

I had a problem like this but had nothing to do with the tune. At about 5000 RPM my card would start going dead lean, Replaced my FPR and that seams to fix it. Guess I was just not holding good fuel pressure.