Tune out Engine Rasp 3800 - 4400rpm
 

Does anyone else experience an exhaust rasp from about mid-high 3000 - mid 4000 rpm range when accelerating anything other than pedestrian speed?

I've had it as long as I have been on Vortech / Full exhaust. I figured it was a header deal, and I have a new one one the way -

But, I was talking to @JeffPerrin today and he said that it was the cam profile timing changing over, and even if you have quieter exhaust that it will still be present, and that you'd hear it through the intake.

He also thought you might be able to tune that noise out, with a very, very small power loss.

Any one else heard of this or done it? Driving me crazy.

Also - for Ref:
Full Vortech Supercharger Kit
Stock Perrin SC tune (Rich, safe)
P&L Catless Header
P&L Overpipe
P&L Catted Front Pipe
Perrin 3.0 resonated cat-back.

enjoy the vtec

If Only. I had a 2004 RSX-S - That was an altogether different sensation lol.

yes happens in a lot of tunes especially for EL headers, its to do with aggressive valve timing/overlap changes to reduce torque dip.


its actually coming from intake in many cases


you either put up with noise or get some torque dip back

Interesting. I'm actually changing headers as well now, going with OFT's UEL Header. Will be interesting to see what that changes. Truthfully, i'm just glad i'll have a header that doesn't intrude up into the engine bay anymore. Like I need more heat up there...

Good to know that's not just me. I am flashed over to E85 EL and I get it right at 4100. Please,post result of going to UEL as that might sell me.

I just got my OFT and tuned the car yesterday. I have the sound you are talking about but the torque dip is gone. Worth it to me.

Pull out 10 degrees of exhaust cam and it'll quiet right down. But as @steve99 said...you'll lose some power.

Might have to do that - It bugs the crap out of me.

uel header cam timing are different and generally dont have to be as aggressive in the 4000 rpm area, so in general you will not get that noise or rassp due tune with a uel header.

i run a uel and no raasp at all :D