Will I get Boost Creep?

[R-U-QUIKR]

I am planning on having a entire exhaust system fabricated from the exhaust mainfold back. It will not include the catalityic converter and will be 3 inch except for the muffler, it will be a 2.5' 5zigen(got it dirt cheap!). Will I experience boost creep? Does anybody know a set up that will not cause creep on the stock T-25? I want to do 3 inch because I do plan on upgrading the turbo when the time comes. Any ideas?

 

[Drifte]

your gonna run 3" then shrink it to 2.5 and go 3" after that? that doesn't sound "high flow". i've read several places that even with a big 16g it doesn't get boost creep and if you do, just port the exhaust or the flapper on the wastegate or somethin. Thats all i remember, hopefully somone with real experience will post soon for ya.

 

[Enraged78]

Honestly, every car is different. If you've still got the T-25, the question is, does it matter? The T-25 can't push more than 15PSI over 5K anyway, so creep shouldn't be much of an issue for you. If you have a larger turbo (14b, 16G, 20G, Garrett H/B etc.) then boost creep, especially on a 3" turbo-back system without a cat, will become more of a reality. There are a few ways to combat it, but the current trend seems to be the following: Port the O2 Sensor housing to match the turbocharger's exhaust housing output, and port out the wastegate hole. If you would like to add a larger flapper, this would be the time to do so. 34MM is nice on a 14B or 16G. If you add a 34MM flapper, 28MM is a decent port (this is the diamater of the old flap). Then, remove the divider between the wastegate housing and the exhaust wheel outlet housing. This allows the bypassed gas to have a very easy path to the exhaust, as opposed to a difficult, turbulant, small path, which will cause the gas to turn the wheel instead of leaving the turbo. If you look at the new IHI turbos, you will notice that the divider is already removed in the casting. Removing the divider will take you TONS of time, but is very worth it.

Matt.

 

[loreak]

its physically impossible for the t25 to creep, unless your trying to hold it at 3psi then it might creep up a psi or two haha....seriously tho t25 = no creep

 

[kpt4321]

Originally posted by Drifte
i've read several places that even with a big 16g it doesn't get boost creep and if you do, just port the exhaust or the flapper on the wastegate or somethin. Thats all i remember, hopefully somone with real experience will post soon for ya.

Wrong. My 14b had really bad creep, over 22 psi, when I put a 3 inch exhaust on. 16g's can be even worse.

Do a search for threads concerning boost creep, they will tell you how to port to remove it. However, the basic idea is you want to remove a lot of material from the wall betwen the WG outlet and the turbine outlet, on the WG side. This gives the gasses a much smoother path to exit the housing. Then, you have to do the same to the O2 housing.

You can probably find someone local to you that can do this work. If not, I can do it for you.

....Kyle T.

 

[Bd1000Eclipse]

3 inch to a 2.5 muffler? ouch.....

 

[R-U-QUIKR]

Hey I realise using a 2.5inch after a straight three sounds ridicolous but I already have the muffler. It wil only stay on for 9 months or so anyways then it will be rectified.

 

[Bd1000Eclipse]

Originally posted by R-U-QUIKR
Hey I realise using a 2.5inch after a straight three sounds ridicolous but I already have the muffler. It wil only stay on for 9 months or so anyways then it will be rectified.

i realize where ur coming from because i have been there before.. but trust me, do it right the 1st time... just sell that muffler and save for antoher one

 

[Talondsm18g]

Originally posted by Bd1000Eclipse

i realize where ur coming from because i have been there before.. but trust me, do it right the 1st time... just sell that muffler and save for antoher one

Yup Save yourself the trouble. And get rid of that honda muffler. Grab your self an N1 or Something else that is freeflowing and sounds nice.