boost creepin...

[97gsssst]

Here is what I have... a b16g and a 3"cat back exhaust, and boost controller. The boost controller is fine. I pluged in my boost source straight to the wastegate and I hit 11psi then by 5k I am at 18-20psi. I fixed an exhaust leak. The only other thing is that it has been really cold out and I dont have a 34mmflapper, but that still shouldn't boost creep as bad as it does. what else could it be???

 

[tim_korn_99]

Here is what I have... a b16g and a 3"cat back exhaust, and boost controller. The boost controller is fine. I pluged in my boost source straight to the wastegate and I hit 11psi then by 5k I am at 18-20psi. I fixed an exhaust leak. The only other thing is that it has been really cold out and I dont have a 34mmflapper, but that still shouldn't boost creep as bad as it does. what else could it be???

I had the same problem with my EVOIII. I then had a 2.5" exhaust system fabbed up by a local shop, from my 3" downpipe back, and that fixed it for me. A little more back pressure, but now it holds boost steadily.
-Tim

 

[dsm10sec]

Internal or extenral wastegate? My internal on my 20g came I think 28mm and I had it ported and put a 34mm flapper in it with an external dump on my o2 housing... Very fast and no creep/spiking. I've heard of that alot with big 16gs and up with internals.

 

[97gsssst]

it's internal and it doesnt have a 34mm flapper, but still do you think maybe just throwing a o2 dump would fix the prob??? :thumbdown

 

[highboosted98]

A External dump will help the problem, However most if the flow is restricted internally in the small passage of the exhaust housing.

 

[dsm10sec]

Just an o2 dump? No, it's either an o2 dump with a 34mm flapper or new downpipe and o2 housing with a 34mm flapper.