what fixes for boost creep?
#1
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what fixes for boost creep?
After being gone for a year, I'm trying to sort out my car again. My biggest problem at the moment is boost creep. While I was gone, my car was used for the FM 3" exhaust prototyping which was then installed on my car. I expect that the 3" exhaust has caused the boost creep problem. The three solutions that I have seen on the forum are:
1: port the wastegate
2: external wastegate
3: restrict the exhaust flow
I took out my MBC to help with the problem, I now have my full RPM range back (was hitting boost cut on the Hydra at about 6k rpms) but even without the MBC, boost starts creeping pretty bad beyond the base 8psi at about 4k rpm, and is at full 14-15psi by redline.
I will be driving from LA to Columbus, OH starting on the 15th of this month to return home, so shipping parts out and back isn't an option right now, and I've got to go > 2,000 miles reliably on the equipment I've got. I'm looking for any possible solutions that I haven't covered. Could my wastegate or actuator be not functioning correctly? The car has probably been sitting still since about April, could rust be a consideration? Is this something that can be cleaned up?
Or do I just have to deal with it and be easy until I get home to start an engine build and look to switch to an external gate?
Turbo is an FM 2560 + associated wastegate hardware.
If nothing else, I'll give FM a ring on Monday and see what they say
1: port the wastegate
2: external wastegate
3: restrict the exhaust flow
I took out my MBC to help with the problem, I now have my full RPM range back (was hitting boost cut on the Hydra at about 6k rpms) but even without the MBC, boost starts creeping pretty bad beyond the base 8psi at about 4k rpm, and is at full 14-15psi by redline.
I will be driving from LA to Columbus, OH starting on the 15th of this month to return home, so shipping parts out and back isn't an option right now, and I've got to go > 2,000 miles reliably on the equipment I've got. I'm looking for any possible solutions that I haven't covered. Could my wastegate or actuator be not functioning correctly? The car has probably been sitting still since about April, could rust be a consideration? Is this something that can be cleaned up?
Or do I just have to deal with it and be easy until I get home to start an engine build and look to switch to an external gate?
Turbo is an FM 2560 + associated wastegate hardware.
If nothing else, I'll give FM a ring on Monday and see what they say
#6
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The only other option is having an external dump for the internal wastegate, similar to what you would do with an external wastegate. Im going to do this to my setup soon in hopes of curing my insane boost creep
#7
more flow overwhelms the wastegate flapper/port causing the turbo to "overspin" so to speak and to boost creep.
That is a waste of money and completely stupid IMHO. You'll have to port the iwg port in order for this to work even SORT OF properly, and still end up with the extra cost and weight of an ewg with none of the benefits. Its not the actual flapper that is causing the creep. It's the size of it and the port its closing/opening.
#8
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That is a waste of money and completely stupid IMHO. You'll have to port the iwg port in order for this to work even SORT OF properly, and still end up with the extra cost and weight of an ewg with none of the benefits. Its not the actual flapper that is causing the creep. It's the size of it and the port its closing/opening.
Im running a restrictive naturally aspirated exhaust so it should be an improvement, the gains would probably be minimal with a free flowing exhaust.
#10
Corky's porting seems to do the trick. UNLESS..... you are using a electronic boost control solenoid. If you are using a EBC unhook it and run off of straight actuator control.
OP- if you are worried about boost creep, your only temporary solution is to unhook the actuator and run boost-less. No fun, I know, but the safest temporary solution.
Stephanie
#12
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The design of the integrated wastegate is flawed. When gases have such an easy time flowing out through the turbine itself, the don't want to actually make their way out the wastegate section. This is due to the shape, size, angle of the wastegate output.
#16
I'm interested to know if JRW's 2560 he has on his S1 kit was ported, because on the same day on the same dyno, his car was creeping just as much as mine. If his was ported by Bell, it didn't solve much. I tend to believe it has not been ported, but we won't know until he yanks the hotside.
#19
I'm interested to know if JRW's 2560 he has on his S1 kit was ported, because on the same day on the same dyno, his car was creeping just as much as mine. If his was ported by Bell, it didn't solve much. I tend to believe it has not been ported, but we won't know until he yanks the hotside.
Stephanie
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