Okay, so I finally put together my sos stage 2 kit on and got tuned yesterday. I made 350whp, and it seems pretty low for my setup. I have the novi 1200 blower, 3.4" pulley, upgraded heat exchanger, 3 inch testpipe and exhaust setup. Most people running the n1200 with a pulley near the size I have hit near 400whp or more. My tuner said I was hitting just about 13 psi but my boost gauge seems to only go up to 10 psi, not sure. The dyno was a dyno dynamics, and he put on a 15% correction because it reads low. Anyone have an idea why I only made 350whp? My tuner also said my coil packs were going bad, would that make such a big difference? I have a 2005 AP2 and im on the AEM EMS series 2. I got tuned at Cartune Performance in Texas. A lot of locals recommended it. If anyone has any input, it'd be greatly appreciated!

 

What injectors do you have?

 

ID1000's

 

Seems low to me, especially AFTER a 15% correction bump. That would mean that your true number on a Dyno Dynamics before correction was sub-300 WHP. That just isn't right. I made nearly that on a Mustang Dyno with the stage 1 kit, Novi 1220.

What fuel pump do you have, and are you still using the stock FPR? Did the tuner mention anything about you running out of fuel or running out of injector duty cycle?

Did you see a plot of your boost pressure while you were there? The discrepancy between your boost gauge and his readings is odd; what boost gauge do you have?

 

Sounds like you need a new tuner...

 

I'm on a walbro 255 pump and stock fPR. And no my tuner didn't mention any of that, only said something about the knock sensor going crazy after he tried to pull more timing. Something like that. And yeah I saw the boost plot, it did show 13 but my aem wideband is showed 10, I mmight'v missed it though if it displayed 13.

 

Don't want to think that but it may be the case...

 

I might have been slightly quick to jump to conclusions but him blaming your coil packs and some of the other things you've mentioned seem like red flags to me...

 

For what it's worth, poor coil packs can reduce power.

 

First thing that doesn’t jive is your 13psi. This is too low for a 3.4" pulley on that blower. You should be netting 15psi minimum and up to17psi. So that can only mean really 3 things, starting with the most likely first. 1. Your SC belt is slipping and or a bad coupler allow boost to escape. 2. The boost gauge is misreading. 3. You have significant engine leak down/blow by problems.

Even at 13psi, a corrected 350whp is low on that blower, which would point to the dyno itself, the operator/tuner providing a lousy run or tune, or once again a nasty engine leak down/blow by.

Coil packs like spark plugs either fire or they don’t, and weak spark will show the same symptoms usually as not firing at all because the spark is too weak to ignite the fuel. These symptoms are easy to depict. They don’t come up as detonation, they come up as a misfire which to the trained ear is very different sounding. Your dyno graph would be smooth and then very choppy when you lose spark and your tuner should be able to depict this from detonation, no timing correction will make a difference in this regard. It could be that he thinks its detonation and is lowering your timing beyond nominal levels providing very low hp readings. What is your spark gap? You should be in the 0.25 range. Can go down to 0.20 to troubleshoot, but shouldn’t need to at your power/set up level.