for those who have after market downpipes...

S

SuperSpud

Member

• Jun 16, 2003

• #1

Im thinking about getting a DP made.. 3" with a 3" hi flow cat.. but then leaving the rest after the cat alone.. so I will be ditching both cats, and putting on a 3" cat..

what will this do for me performance wise? is it even worth it? seeing as how the rest of the exhaust is so small? I cant do the whole turbo back b/c of dad issues, but I figured that getting rid of a cat would help a little...

help me out here... I know that I HAVE to keep the muffler on there.. where is the resenator? is it on the dp? or mid pipe?? is it worth getting rid of too??

 

S

Swerny

Member

:

2008.5 Mazda 3 Sport GT

• Jun 16, 2003

• #2

As far as I know, there are 2 cats and a resonator on the downpipe.

Nothing says you have to keep the muffler. Actually. AGR #7 and Memphis Racer have a straight pipe they are selling to eliminate the muffler altogether.

I am interested in this too, i'd like to run a new downpipe, with straight pipe all the way back.

I am debating the high flow Cat idea too.

MS MSP #143

 

Last edited: Jun 16, 2003

A

Apexi

Member

• Jun 16, 2003

• #3

3", 2.5" same thing really under 300whp...except the 2.5" will be quieter, and less chance of boost creep

 

S

SuperSpud

Member

• Jun 16, 2003

• #4

Apexi said:

3", 2.5" same thing really under 300whp...except the 2.5" will be quieter, and less chance of boost creep

Click to expand...

thats what I was about to ask... is it going to be a lot louder with the bigger dp? I wouldnt think it would be to loud b/c I would still have the stock piping afterwards.. and I would still have a cat on there...

what size is the stock dp?? would 2.5" be any bigger?

 

B

blynzoo

Member

Contributor

:

'02 Red P5...BUT AS OF 1/31/08 an '08 Silver SPEED3!!!

• Jun 16, 2003

• #5

Stock exhaust piping is 2.25. Often the DP is bigger slightly. Not sure here.
Some say 3" is the limit of necessity for the 2.0 F/I, some say 2.5 is all you need. Folks here run everything from 2.25 to 3".

 

T

Turbo Matty P

Banned

• Jun 16, 2003

• #6

I'm selling an exhaust pipe that will enlarge the downpipe from 2.25" to a 2.5" mandrel bend, eliminate both cat's and still bolt up to the factory resonator piping and sport muffler. I have it on my car and it's a big difference. Sound is much better (louder) and the mid to topend power is real good. The turbo spools up much faster (as if it could) and the extra pull on the topend is just what we need for those long quarter-miles. If you're interested in what I have PM me or email to SVTMATTY@BELLSOUTH.NET. I'm getting orders together now. Thanks.