Hey so I've been through all of the posts here about test pipes and rasp...but no one seems to say anything other than to get rid of them. I work for Mercedes and talked to a fellow mechanic about any fixes and he told me a few things.

I just want to see if anyone out there might be running the same setup as me and was able to get rid of the rasp

Long tube cai k&n
Hks replica exhaust
Berk test pipes
Headers (not in yet)

He told me that I've opened up this airflow and eliminated my back pressure. He said that when I put on the am headers (stock is more restrictive) that it will help the tone and get ride of some rasp. He also stated that the car is tuned stock...so having a car that is tuned daily trying to be run on the track, I will run into sound and performance issues. He ultimately said that after putting in headers and tuning it professionally I will get rid of the rasp. Or at least get it to subside

Let me know what you all think and those of you who have successfully gotten rid of this sh** can sound, please chime in

First post also

Thanks
David

 

you are going to have rasp unless you leave factory cats.

you will need to tune asap, will all that you are doing you will be running pretty lean

 

From what I have read here, I have no experience, resonated test pipes like the motordyne ART pipes help to reduce the rasp of the VQ.

 

Thanks for quick responses travlee and rancor

I'm thinking of throwing on my headers and seeing if it helps at all. Guessing it won't. If that is the case I'll keep those on and throw my cats back on. While I'm on the rasp topic , will removing my stock headers and throwing on am headers give me the same raspy tone? I'm doing this for (what I thought would be) a much nicer exhaust tone...the gains to the wheels are almost unnoticeable besides throttle response. If they will just add to the fart can tone I will just avoid the struggle of putting them in

Thanks!

 

the headers will definitely make it 10x worse from my experience. I took my headers out because i couldnt take it. You could do ART pipes which will sound good but they cost a ton compared to regular test pipes.

 

Were you running any specific tune for that?
I'm thinking of just getting hfc and throwing on the headers then tune. After my paycheck I'll decide if I want to commit to the hfc or go back to stock cats

 

I have a DE, but after i put on my shorty headers the rasp grew louder,last longer, and is higher pitched then before. That is with TP's and stillen exhaust.

 

HFC will help the rasp a bit, especially if theyre ceramic cats. the metal ones still retain more rasp. I had an accessport at the time with stage 2+ tune but it doesnt make a difference as it will still rasp bad without cats.

 

Ok I think you all have helped me decide to just throw the headers on and stick with cats. Thanks everyone also for not roasting me on my first post

Stay frozty peeps

 

so you are going to free up air flow, just to turn around and restrict it with cats? seems counter productive

 

HFC aren't really that restrictive.
Stock headers + TP = slight restriction and rasp
AM headers + HFC = slight restriction and a little less rasp

 

Unless I'm wrong please let me know travlee

 

it will add some restriction, but will it be horrible? ... nah. are you putting the headers in, or is a shop

 

I am, got my coworker from benz coming over with some extra tools I don't have to help me along with it. he's been a mech for 20+ years ish

 

let me know how much you cuss, and how long it takes ya

 

yea have fun with the headers. youll have to drain cooling system to get to them!

 

Haha ok I'll keep you posted. At Mercedes they use something called ALLdata which is some high end step by steps and he got the z headers printed out. Hopefully it's as easy as he says. But he also does this for a living haha

 

took my buddy, a good part of 8 hours to do his

 

Wait, you're going from a 2.25/2.5 collector down to a 2ID cat? Ouch

 

WOW!!! I'm going to just sell my car now thanks for letting me know about this vital flaw in my plan