Boost creep?
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Joined: Jan 2005
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Boost creep?
Ever since I got evoIII 16G I can not control my boost with open exhaust. It hits like 23 psi and probably more but I just dont want to step on it to find out how high it would go 
The problem does not exist with the silencer in. Silencer produces back pressure and it help somehow. I dont know what it is from what I've read on dsmtuners that could be a boost creep? Please help me out guys, I want to get rid of that BS.
I got the turbo from sbr it has 34mm flapper, inlet and outlet ported
The other mods are:
ported manifold exhaust
tubular o2 housing from sbr
megane downpipe with no cat
tanabe super medallion cat-back
fmic with stailess steal pipes
FIPK with aluminium intake
Blitz BOV
FIC 550cc injectors
Safc2
Profec B II
walbro 190lph
ACT 2100 with act flywheel
and some more but not that important and I dont remember now
What should I do ?
The problem does not exist with the silencer in. Silencer produces back pressure and it help somehow. I dont know what it is from what I've read on dsmtuners that could be a boost creep? Please help me out guys, I want to get rid of that BS. I got the turbo from sbr it has 34mm flapper, inlet and outlet ported
The other mods are:
ported manifold exhaust
tubular o2 housing from sbr
megane downpipe with no cat
tanabe super medallion cat-back
fmic with stailess steal pipes
FIPK with aluminium intake
Blitz BOV
FIC 550cc injectors
Safc2
Profec B II
walbro 190lph
ACT 2100 with act flywheel
and some more but not that important and I dont remember now
What should I do ?
15 seconds EXHILARATION
Joined: Jun 2002
Posts: 7,801
Likes: 0
What does the boost hold at with the silencer in? How long are the lines from the b.c. solenoid to the wastegate actuator and turbo?
As I see it your problem has to be something very simple or it's going to be a bitch to fix. Unless it's settings on your boost controller or something wrong with the boost controller/b.c. install (lines, electrical)/something wrong with wastegate actuator, it seems like you're going to have to- at the minimum- pull the turbo and port it in an attempt to get more exhaust flowing out of the wastegate side.
The very first thing I'd do is try to find a guide to setting up a Profec B spec II. Those things suck- they're finicky and sometimes hard to get dialed in. The control I'm thinking of is the gain, the boost response control- it might be that you're simply spiking to 23 and the boost would fall off and hold at a lower level, and you might be able to fix that with the gain control. Have you stayed in it at all or have you simply pegged it, seen it shoot up past 20 and let off? I cannot recommend staying in it on some unknown boost level for obvious reasons, but if you've already done it at least you'd know if it was just a spike.
All the other stuff is iffy. Slowboy should have been competent enough to port the turbo correctly to prevent creep/spike, and to make full use of the 34 mm flapper. With that flapper and porting, you should have trouble holding high boost, not trouble staying under 20 psi. If none of the stuff above works and you pull it to port it, I found a very good guide on dsmtuners that shows you exactly what to port to increase flow through the wastegate. In a nutshell you're cutting a deep channel straight to the wastegate path, taking away some of the taper of the turbo inlet in one spot on that side, and then you add the standard port on the wastegate outlet that should have been done with the flapper install, taking it as far out as possible while leaving a safety margin for sealing. I just hate to tell you to pull a turbo that shouldn't need to be ported while it could be some other problem, so check all of the other stuff first. It just seems like you've got all the bases covered- flapper, porting, tubular o2, etc. I would check everything else first.
As I see it your problem has to be something very simple or it's going to be a bitch to fix. Unless it's settings on your boost controller or something wrong with the boost controller/b.c. install (lines, electrical)/something wrong with wastegate actuator, it seems like you're going to have to- at the minimum- pull the turbo and port it in an attempt to get more exhaust flowing out of the wastegate side.
The very first thing I'd do is try to find a guide to setting up a Profec B spec II. Those things suck- they're finicky and sometimes hard to get dialed in. The control I'm thinking of is the gain, the boost response control- it might be that you're simply spiking to 23 and the boost would fall off and hold at a lower level, and you might be able to fix that with the gain control. Have you stayed in it at all or have you simply pegged it, seen it shoot up past 20 and let off? I cannot recommend staying in it on some unknown boost level for obvious reasons, but if you've already done it at least you'd know if it was just a spike.
All the other stuff is iffy. Slowboy should have been competent enough to port the turbo correctly to prevent creep/spike, and to make full use of the 34 mm flapper. With that flapper and porting, you should have trouble holding high boost, not trouble staying under 20 psi. If none of the stuff above works and you pull it to port it, I found a very good guide on dsmtuners that shows you exactly what to port to increase flow through the wastegate. In a nutshell you're cutting a deep channel straight to the wastegate path, taking away some of the taper of the turbo inlet in one spot on that side, and then you add the standard port on the wastegate outlet that should have been done with the flapper install, taking it as far out as possible while leaving a safety margin for sealing. I just hate to tell you to pull a turbo that shouldn't need to be ported while it could be some other problem, so check all of the other stuff first. It just seems like you've got all the bases covered- flapper, porting, tubular o2, etc. I would check everything else first.
Thread Starter
Registered User
Joined: Jan 2005
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Originally Posted by Jordan Y.
What does the boost hold at with the silencer in? How long are the lines from the b.c. solenoid to the wastegate actuator and turbo?
I don know about the lenght of the lines... will check them out in the morning.
Originally Posted by Jordan Y.
As I see it your problem has to be something very simple or it's going to be a bitch to fix. Unless it's settings on your boost controller or something wrong with the boost controller/b.c. install (lines, electrical)/something wrong with wastegate actuator, it seems like you're going to have to- at the minimum- pull the turbo and port it in an attempt to get more exhaust flowing out of the wastegate side.?
Is there anybody here that could help me with that and how much would it cost me?
Originally Posted by Jordan Y.
The very first thing I'd do is try to find a guide to setting up a Profec B spec II. Those things suck- they're finicky and sometimes hard to get dialed in. The control I'm thinking of is the gain, the boost response control- it might be that you're simply spiking to 23 and the boost would fall off and hold at a lower level, and you might be able to fix that with the gain control. Have you stayed in it at all or have you simply pegged it, seen it shoot up past 20 and let off? I cannot recommend staying in it on some unknown boost level for obvious reasons, but if you've already done it at least you'd know if it was just a spike.
Thanks for your input Jordan
Eis Aner Oudeis Aner
Joined: Feb 2003
Posts: 4,503
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Originally Posted by AnthrAxNSB
...or purchase and install an external wastegate that flows more air.
Do all that Jordan told you, also you might want to just try a MBC and see if that does anything.
Too Much is ALMOST Enough
Joined: Aug 2003
Posts: 5,670
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Double check the lines for the bc. I was setting my mbc and when I adjusted it one of the lines hit the something hot and burned a hole in it. I got on it and saw 26psi 
So I kept adjusting it and samething each time. It took me about 20 mins to figure it out 
So I kept adjusting it and samething each time. It took me about 20 mins to figure it out
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