Al

first of all i did search and see topic by Turbulance where you guys discussed 2uniqes boost creep but it only helped a bit

By installing a good external waste gate does it eliminate any chance boost creep?

and if there is no ext. gate are there other ways of avoiding it?

PS:assume that full exhaust, proper downpipe
Edit: yes i did read that book on turbos,but i cant remember it talking about this exact or similar situation

[ February 13, 2003, 09:04 PM: Message edited by: Big_Al ]

Random

Boost creep can be cause by many things, but usually it is either wastegate flow impeded by exhaust flow coming out of the turbine (internal or external can do this), or by a wastegate that is just too small for the required flow.

If you use some form of boost controler, it can cause boost creep as well, as the boost controler alters the pressure signal to the wastegate.

In general, with an external wastegate and a good merge pipe design for the wastegate flow, and a decent boost controler, you should have no problems.

Al

what boost controller would you recomend Random?

Random

Depends on the application.
What turbo
What wastegate setup?
What boost level?

Most boost controlers work fine at 20psi or lower, but some have real issues with high boost applications.

Some boost controlers also have problems with very low boost setups 5psi or less.

Al

i am not sure what ex gate or torbo(something small like t3/t4 since i want boost at low rpm) i will use but i know that i will start out with very low boost 5-7psi

[ February 14, 2003, 06:24 PM: Message edited by: Big_Al ]

Agarwal

Hmm... a T3/04 is actually pretty big for the Alpha. If you intend to run low boost (say 5-12psi), I'd suggest something smaller, like a T25, a T28 or T3. Look at the turbo maps to find out what turbo would be best on your car, considering the boost you want to run. Don't forget that with a smaller turbo, the boost usually kicks in earlier, which is definitively an advantage.

[ February 14, 2003, 06:35 PM: Message edited by: Agarwal ]

Al

great thanks, where can i find these turbo maps ?

2 UNIQ

Boost creep is something you donty want to encounter.As random has mentioned an EXTERNAL wastegate and installed all all 4 collectors on the Turbo manifold will eliminate your boost creep.Dont install an External wastegate for LOW boost as an internal wastegate will do the trick.IF after you install your Turbo and you encounter Boost creep do some tests to determine WHY its creeping like WIRING the wastegate WIDE OPEN and if you hit high PSI then you know your internal gate opening is to small.
After all this you can then install an External wastgate
I hit a solid 10psi with my wastegate wide open thats why im forced to install an External wastegate to eliminate my creeping and at teh same time it looks nice when its installed smile.gif

turbulence

well, if you read maximum boost (i'm assuming that's the book you're talking about), you'll have the knowledge to calculate the flow requirements of a compressor for your turbo. if you don't know how to do this, read the book again. don't get a t3 because another kid with an alpha engine has one. get a t3 because you researched it, and the compressor is the right size and will perform effieciently for your intended goal. after you've worked through the math (it's really quite simple), go to www.turbonetics.com and look at compressor maps until you find one that suits your needs.

CNK Performance

Rearding the boost creep -- fist confirm that your hardware and design is put together properly, before buying a controller --- remember the controller is dependant on the H/ware in the first place, so start there first before spending un-necessarily