Nothing, if you want a gain without creep you're gonna have to port the turbo. You wasted your money on a downpipe that is the exact same design as the stock, but is illegal now because you have no cats. If you want a cheap quality piece buy the stromung$200, bosal$220ish, or the helix$280or$200 used(this one also rids you of both cats) the prior two let you keep your stock 2nd cat or a high flow metal substrate.

Look at the diference ...
HKS

Helix

Daddys' (if you're not on a budget and live somewhere with strict emissions laws hock that piece of crap hks on ebay and get this one)

 

pde downpipe! probably not the best flowing dp but no creep, no cel, good quality and good gains.

hks dp is junk imo!

 

Any decent exhaust will cause boost creep, if your car is one of hte ones that is inclined to do it in the first place. Not all will do it. Also, you can get the boost creep eliminated with a reflash, I've personally ridden in 5 STis with full 3" catless turbobacks that do not exhibit boost creep. Go with the highest flowing exhaust you can.

 

alright thanks a lot. I wish you guys could have helped me out a little before. I always would ask but no1 would help me. I might just keep the downpipe for the time being because i dont wanna creep

 

Umm, your first post here was "I just got HKS Hi-Power exhaust..." If you had asked about it I would have posted up exactly what I did in this thread. Sorry you asked in the wrong places. Also, a search for "HKS downpipe" would certainly return the same opinions and statements from myself and many others, here and elsewhere.

 

Why is the pde so good? Because it's the most expensive? It looks like the EXACT same design as the helix and just about evey other quality bellmouth, but 2-3 times more expensive? Also, how would you not get a cel with no cats? Does it have magical anti-cel powers or something? It doesn't make sense,

 

You can eliminate cats with mechanical and electronic means. Quality and R&D are another reason why some parts cost more.

 

That's right I forgot about the cool "elbow bung" on the pde.

Although, I used the $5.00 kragen mech. fix on my helix and it worked great