Engine missing at high rpms
 

I have a 2008 Mustang Gt with the following bolt ons

Pypes shorty headers
Pypes off road x pipe
JBA mufflers
BBK twin 62mm throttle body
C&L racer intake
Diablo tuner

At high rpms it sounds like it starts to miss a little, anyone know what this could be?

My Cobra does the same thing after switching out the off road x-pipe for high flow cats to pass the emissions. I don't know what it is, it sounds as if the belt is slipping on the supercharger, but then again it sounds as if the exhaust is just cutting out. We had it dyno-tuned for the off-road pipe, but that shouldn't change anything. It's only in the high rpms like you're saying.

Does the Diablo throw up anything??

Was your car dyno tuned, or are you using the standard tune that came on the Diablo?

The tuner says nothing. The tuner has a tune that I ordered in it for the bolt ons that I have installed..

How much difference do you think a dyno tune will make? $500.00 for a dyno tune here!

How are those 4:10 gears working out for you? Are they too low for the interstate? I am gonna change mine real soon but I was gonna go with 3:73. What do you think?

Umm I'd never get 3:73's after getting 4:10's....It doesn't run hard on the interstate, but it is a little bit higher than stock (duh). If you're real worried about it you can get 3:90's which still feel pretty damn sweet. I put 4:10's in the Cobra when I first bought it, and every Mustang I've ever worked on stick or automatic has had 4:10's....

So i my opinion I'd get 4:10's and try them out. If you think it's too much than drop down to a lower gear and sell the 4:10's (the worth doesn't fall on gears if you explain that they were just to test, trust me)

so is the engine still missing or what? did you fix your tune?

Did the miss start happening after you installed that tune?