Is it anygood? How much power increase can I expect with this set-up with up-pipe? Does it make any difference in sound?thnks

 

Do not get a HKS Downpipe!!!! It's not bellmouth!!! Get Helix or Invidia

 

lot of mixed opinions and debate on this but generally if you are going to stick with your stock turbo, an hks downpipe will suffice for power. you wouldn't notice any difference between the hks and some other bellmouth. but if you are going to (or planning to) upgrade your turbo you might as well get a bellmouth or divorced wastegate downpipe now, although people with the hks downpipe have made really good numbers even with upgraded turbos. i'd say if you are tight on cash just go for the hks because you probably won't feel any difference. and sound will be the same.

 

There are quite a few people that have made big #'s with an HKS DP (even with big turbos).

Look at some dyno plots and make your own assessment.

 

I got engine management first, then a gutted up-pipe, but the biggest gain I got on the dyno was getting a catless helix dp...it made a big difference in the butt-dyno too, but the noise levels stayed the same cos I stuck with a stock muffler. No cats plus EM on wrx = 200whp, and that's on a stock intercooler, hoses and cat-back.

 

The Cobb downpipe is a great choice.

 

I had the HKS and was very happy with it. Now I have switched to a bellmouth from tsudo. The hks fit a little better but I am happier with the bellmouth

 

i felt a difference in torque and a faster spool. its pretty loud too, i got a state ref ticket but its back to catless again..ITS SO MUCH BETTER!! for the money you cant really go wrong. i havnt put it on the dyno yet but we'll see when i go to Vishnu soon.

 

i had a hks downpipe for a while, i had crazy boost creep, it went away when i put my helix downpipe in, i found that the helix had better fitment and went in a hell of a lot easier than the hks one

 

I HAVE A HKS DOWNPIPE FOR YOU>>>I HAD IT ON MY 04' sti for about 3 months... i liked it a lot... i painted it black... in case i got pulled over, i would say it's the driveshaft ....if you want it you can buy it from me for 100 + shipping unless you want to pick it up... anyway... i don't have a use for it anymore... let me know... 707-310-6767

 

i thought hks downpipes already come in black color

 

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thanks guys! ended up getting a helix dp.

 

I have an HKS downpipe but I converted mines to bellmouth plus I heat wrapped it and it feels alot better. ( and yes he cleaned it up before welding the bellmouth piece) Luckily I have a friend that does custom work. Anyways here's what he did.

 

good man