Hey guys was have a random convo with a buddy of mine earlier about what would be better so i thought i'd throw a thread up on here, so here's the thing imagin a standard 8 MR, wich would be the better mod out of these 2... 3" downpipe and decat with the stock catback, or stock downpipe and cat with a 3" catback

random question i know lol, but dont say a full TBE

 

The latter of course. Always start from the rear and work your way to the O2 housing.

 

You'll see more gains with a downpipe + testpipe than you will with a just catback. The stock Evo muffler actually flows pretty well, especially the IX version.

 

This is just a guess, but...

I would say, 3'' downpipe and decat, you will not get the benefits of the 3'' piping probably since it will later neck down to the stock cat-back, but you will get the benefits of not having a cat, which I would think would be more then the benefit of expanding your piping after the restriction of your cat.

 

This.

Dont forget, exhaust gases, like anything else, are hottest closest to the turbo. As they travel down the exhaust they cool and contract. Having a larger space for the exhaust to evacuate where it is the least dense (near the turbo) will always yield more gains (less back pressure).

 

I would say the downpipe and decat. Most of the power will come from the decat as it is obviously the biggest restriction. The stock catback is a decent size, not horribly restrictive.

 

Thats what i thought, i currently have the downpipe and test pipe on my car now. but due to it not being tuned yet i cant run the catback due to over boost and fuel cut wich sucks because it sounds great! so in the mean time its 1 or the other...

tuning prices over in england are ridiculous!

 

Why not try one of our remote tuners like Mellon?

 

i did look into those but wasn't sure how good they'd be for me as im over seas with different octane fuel, humidity etc?

 

That factors into the entire tuning process. As long as you are sending him valid logs he should be able to tune for all of those factors.

 

Think i'll have to have a deeper look into that then

in the mean time do ya'll think i could get away with putting the catback on if i put the cat back in? that should help stabilize the boost right?

 

Mellon tunning ftw

 

niether
I'd wait till I could to a full TBE and a tune.....that just my opinion.

 

if you gotta be cheap about it...go on ebay and buy a full TBE...theres no excuse to not buy a TBE...lol

 

i have a full turbo back, but as the car is stock pretty much stock with the full turbo back fitted it was causing the car to over boost

and as im in england everything is over priced, for example just to get ecutek and a map companys are asking like £600! ($915) and no1 seems to offer ecu flash

so i was basicly just looking for a temporary solution as theres somthing about a quiet *** evo with a stock exhaust just doesn't seem right lol