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Red91GSX
04-20-2003, 05:09 PM
91 GSX ... with a ported 14b, mbc and BR UICP. I am now adding a 2.5" Downpipe, 2.5" Testpipe and 3" catback (all Buschur).

Will I be seeing boost creep at all?
Tra2xx
04-20-2003, 10:16 PM
Port the O2 housing (especially where the wastegate part is) and port the actual wastegate on the turbo, enough so the flapper can open basically all the way. Then you should be good. On a non ported O2 and wastegate, you will have creep especially with a test pipe.
Red91GSX
04-21-2003, 07:14 AM
Cody (Previous owner) has ported the 02 housing and the wastegate as much as possible.

Also, what if I had a 2.5" catback instead of the 3"? Would that help?
v413nc3
04-21-2003, 03:19 PM
The correct way to control boost creep is to not restrict your exhaust but to open up the passage for your wastegate. I see people do this backwards all the time. If the wastegate is ported and the O2 housing for it is ported (ported well at least) You shouldn't be running into problems with boostcreep on a 14b. I run a FULL 3" exhaust on a 14b and it doesn't budge past where I set the MBC... keep in mind though that your setting for the MBC will be a lower PSI in 1st and 2nd gear and higher in third, and then higher in 4/5th... So generally I suggest setting your boost levels to optimum in 4/5th and dealing with slightly lower levels in 1-3rd... (it usually only varies by 1-2psi).
Red91GSX
04-21-2003, 09:50 PM
Originally posted by v413nc3
The correct way to control boost creep is to not restrict your exhaust but to open up the passage for your wastegate. I see people do this backwards all the time. If the wastegate is ported and the O2 housing for it is ported (ported well at least) You shouldn't be running into problems with boostcreep on a 14b. I run a FULL 3" exhaust on a 14b and it doesn't budge past where I set the MBC... keep in mind though that your setting for the MBC will be a lower PSI in 1st and 2nd gear and higher in third, and then higher in 4/5th... So generally I suggest setting your boost levels to optimum in 4/5th and dealing with slightly lower levels in 1-3rd... (it usually only varies by 1-2psi).

Well, the porting was done by Cody with only hand tools, so I am not sure if that would be enough. I guess I will just see when it goes on.

Thanks for the help though!