alright guys. i got a 2009 factory JCW.

i was initially thinking of gutting out the primary cat and resonator from my factory jcw exhaust to really open up it's sound and make some hp gains as well.

however, recently i've been hearing about how excellent riss racing's catless coated downpipes are.

my question: would running a catless factory jcw exhaust yield the same performance gains as installing riss racing's catless downpipe?

 

I think the HP gain is neglible. I installed a Exhaust Depot cat (which is catted) and to be honest, I'm not sure if I would want to deal with a CEL for the neglible HP difference.

My .02 worth...

Mark

 

keep it clean...keep the cat

 

i mean, the title does clearly state catless.
not trying to offend you lhoboy but im looking more for help, rather than opinion.

however, thank you for the opinions so far

 

Do not destroy your factory downpipe by "gutting" the cat! You'll need it when you go in for a emissions check, granted your state checks for that stuff.

The downpipe that will definitely give you a gain in power/torque is a catless pipe. Your turbo will spool quicker and it you will definitely feel the difference right away! Going catless on a R53 didn't make much difference and it made the car absolutely obnoxious, but the R56 will be quieter.

 

Buy a catless downpipe and dont gut the factory downpipe.

 

I don't kno if there is a difference between the two on this forum but I meant "taking out" the cat on my stock downpipe, not "gutting" it.

If I were to remove the primary cat couldn't I have it installed back in as well? Oh, and don't worry about passing inspection. My friend owns a shop and can pass me

 

If cutting away at the OEM downpipe, taking the cat out, and repairing the hole you've just made is easy to you... then go right ahead

Just keep the OEM downpipe and buy another catless downpipe. Swap them back and forth as needed.

 

Yikes, I wouldn't post on a public forum how your friend will fraudulently pass your legally mandated emissions test...

But, if your friend has a shop, just have him fashion you a catless downpipe... it literally is just a pipe, so he shouldn't have any issues.

 

buy a real catless DP. its worth it, the factory one is very restricted on the end by the turbo. this way if you resell your car you can give them the stock one if they want it to pass emissions.....if they dont have a friend as nice as yours