APS downpipe cause boost creep.

siusti · 10-24-2006, 09:54 AM

I am currently sitting on Top Speed waiting on my car to start acting properly. It has some bad boost creep. Doug took off the actuator to ensure it was the exhaust and not the wastegate. Sure enough, more creep.

He said that he has removed the divider in the APS exhaust in the past and it has solved the creep problem. He took the downpipe to a machine shop real quick to get that divider out.

Ill post if that fixed the problem.

**Interior Flaire** · 10-24-2006, 10:04 AM

I just ordered my UR uppipe with a Tial 38mm WG to solve my creep problem. DP vains, porting wastegates, manual boost controllers, blah, blah, blah. I know after going around the world, asking 3 of the 5 top tuners in the country and countless other vendors and the manufacturer of my turbo, an EWG is the only sure thing that will cure the dreaded 20G creep problem.

CB

docwyte · 10-24-2006, 03:13 PM

Do all 20G's boost creep? Do you think you still would've had boost creep with an FP Green? I plan on doing one or the other...

daemon · 10-24-2006, 03:15 PM

If the APS downpipe causes creep where others don't, then I'd say the APS downpipe is the better downpipe.

siusti · 10-24-2006, 04:58 PM

I'd actually say that APS isn't the better downpipe.

daemon · 10-24-2006, 05:30 PM

I said "if..." not was. In essence creep is being caused by increased exhaust flow. If the APS creeps where the others don't, it would seem it is less of a restriction than the others. Do you have a different angle?

I suppose on the other hand, one could argue that it is blocking the wastegate flapper in such a way as to reduce the ability of the wastegate to flow. Thus forcing more exhaust through the turbine. I don't personally claim to know which is the case. Just talking out loud. Hope that doesn't offend anyone.

siusti · 10-24-2006, 05:43 PM

I dont know if I have a different angle. The boost creep was actually found to be a bad turbo after exhausting all options. Doug has been working with FP today on the issue and FP is sending a prototype exhaust housing gaurenteed not to creep.

daemon · 10-24-2006, 05:53 PM

That's cool. Hope it works out for you and I'm glad the source of the problem is getting fixed.

10-24-2006, 09:54 AM	#1
siusti Grassroots STI Racer Car: 04 STi Posts: 580 Join Date: Oct 2005 Trader Rating: (0)	APS downpipe cause boost creep. I am currently sitting on Top Speed waiting on my car to start acting properly. It has some bad boost creep. Doug took off the actuator to ensure it was the exhaust and not the wastegate. Sure enough, more creep. He said that he has removed the divider in the APS exhaust in the past and it has solved the creep problem. He took the downpipe to a machine shop real quick to get that divider out. Ill post if that fixed the problem. This ad is not endorsed by this member. Please register or login to hide this ad.

10-24-2006, 05:30 PM	#6
daemon The Next Petter Solberg Car: 2004 STi Location: Florida Posts: 865 Join Date: Feb 2004 Trader Rating: (0)	I said "if..." not was. In essence creep is being caused by increased exhaust flow. If the APS creeps where the others don't, it would seem it is less of a restriction than the others. Do you have a different angle? I suppose on the other hand, one could argue that it is blocking the wastegate flapper in such a way as to reduce the ability of the wastegate to flow. Thus forcing more exhaust through the turbine. I don't personally claim to know which is the case. Just talking out loud. Hope that doesn't offend anyone. Last edited by daemon : 10-24-2006 at 05:33 PM.

10-24-2006, 05:53 PM	#8
daemon The Next Petter Solberg Car: 2004 STi Location: Florida Posts: 865 Join Date: Feb 2004 Trader Rating: (0)	That's cool. Hope it works out for you and I'm glad the source of the problem is getting fixed. This ad is not endorsed by this member. Please register or login to hide this ad.

10-24-2006, 10:04 AM	#2
Interior Flaire Authorized Vendor Car: 05 PSM Stage 4 Fav Mod: Pro-Tune Location: Big D Posts: 1,745 Join Date: Apr 2005 Trader Rating: (16)	I just ordered my UR uppipe with a Tial 38mm WG to solve my creep problem. DP vains, porting wastegates, manual boost controllers, blah, blah, blah. I know after going around the world, asking 3 of the 5 top tuners in the country and countless other vendors and the manufacturer of my turbo, an EWG is the only sure thing that will cure the dreaded 20G creep problem. CB

10-24-2006, 03:13 PM	#3
docwyte Senior STI Driver Location: denver, CO Posts: 337 Join Date: May 2006 Trader Rating: (1)	Do all 20G's boost creep? Do you think you still would've had boost creep with an FP Green? I plan on doing one or the other...

10-24-2006, 03:15 PM	#4
daemon The Next Petter Solberg Car: 2004 STi Location: Florida Posts: 865 Join Date: Feb 2004 Trader Rating: (0)	If the APS downpipe causes creep where others don't, then I'd say the APS downpipe is the better downpipe.

10-24-2006, 04:58 PM	#5
siusti Grassroots STI Racer Car: 04 STi Posts: 580 Join Date: Oct 2005 Trader Rating: (0)	I'd actually say that APS isn't the better downpipe.

10-24-2006, 05:43 PM	#7
siusti Grassroots STI Racer Car: 04 STi Posts: 580 Join Date: Oct 2005 Trader Rating: (0)	I dont know if I have a different angle. The boost creep was actually found to be a bad turbo after exhausting all options. Doug has been working with FP today on the issue and FP is sending a prototype exhaust housing gaurenteed not to creep.