need help boost creep after protune

Trum1982 · 10-21-2006, 06:40 AM

ok guys i have a problem i have had so many different things said to me. i will start at the beginning.

i have a cobb ap with aps tbe injen cai and walbro 255 fuel pump.
i got protuned last wednesday. i was told i had terminal mechanical boost creep right at 5000 rpms my boost starts to go up instead of tapering off.
now here is what i was told. i could port wastegate by the tuner, i asked other tuners and they said no way do not port the wastegate. i could try a different exhaust since the aps has a divider going into the turbo the wastgate opens and hits the divider. but the guys at agile auto says they tune cars all the time with aps with no boost creep. last option get a bigger turbo wich i plan to do but not for like a year no money right now. can someone plz help me thanks

Trum1982 · 10-21-2006, 08:03 AM

guys i need some help so any one with any info would be great. i also have some data logs if anyone knows anything about tuning.

**evilSTi7** · 10-21-2006, 08:10 AM

ok, well if you can find someone who has ported other stock wastegates that is certainly an option.

Another option would be to get an external wastegate. that will cure your boost creep for sure, but it's expensive (probably around 600 for the parts) and you'll need to get retuned for it.

Are you catless? If you are you could try swapping the aps cat onto there and that might help a little, but probably won't totally fix it.

crystal_Imprezav · 10-21-2006, 08:35 AM

Who was the tuner? It is pretty easy to tune out creep at higher rpm's with WGDC's and turbo dynamics. I personally would not port the wategate due to the fact that it needs to be done prefectly or you will just not hit target boost ever. The harder creep to tune out is in the mid rpm range where boost peaks and it is possible to see spikes at higher gears.

Trum1982 · 10-21-2006, 09:20 AM

i have no cat i am currently talking to jermey at agile i sent him some of my data logs and he said he would look at them to see what is going on. i also have a ebcs on there and that didn't help. i was told by jeremy and hill not to portwastegate. so i am kinda of stuck

crystal_Imprezav · 10-21-2006, 09:35 AM

The EBCS is probably the culprit. It holds boost more stable so thats probably why it continues to boost up top. It takes more fine tuning to get the boost settings correct and I am sure the Agile crew will take care of you. What is the boost rising to up top? If you post a log I could better give my opinions.

WXRTSI · 10-21-2006, 09:49 AM

Gl with all that man. Has any1 ever experieced boost creep on stg1?

Trum1982 · 10-22-2006, 09:20 PM

do you guys think it might help if i changed my dp since i have a 3 aps and the dp has a divider. i was told when the wastegate opens it doesn't open all the way and it releases gas right into the divider which causes boost creep. should i change exhaust and get a bellmouth.

WXRTSI · 10-22-2006, 10:38 PM

It's definitely worth a shot. U won't know unless u try, but from the sound of things it makes perfect sense.

***Tomerville*** · 10-22-2006, 11:09 PM

I'm not familiar with APSs DPs, and the swappable Cat, but if you purchase a catted downpipe, and then get a retune, you could have gotten an EWG for that price, and then you are guaranteed not to get the creepies.

I am catless and when its below 40, I get some creep issues in 5th gear, and only 5th gear. Since i'm going with a different turbo setup in a month or so I'm just holding out until I go EWG and Protune.

Basically, i'm just saying that investing in getting rid of boost creep is largely based on your future plans and budget.

crystal_Imprezav · 10-23-2006, 05:28 AM

The APS DP has a wastegate divider which in its production form the extra material and angle can cause creep. Nhluhr has a write up about it somewhere and how to grind it to smoothness to eliminate the problem. Search him or search the forum to find the post.

kts262 · 10-23-2006, 06:20 AM

Quote:

Originally Posted by evilSTi7

Are you catless? If you are you could try swapping the aps cat onto there and that might help a little, but probably won't totally fix it.

I just installed the APS TBE w/ cat this weekend (removed my TXS exhaust) and I'm getting boost creep. Not as bad as it would probably be catless but my 15psi daily driving map was hitting 17... 18...19psi before I let off the throttle and that was only around 5k rpms. Haven't hit fuel cut yet but I'm also scared to try my "all out" 19psi map with the APS installed. Time to go porting...

**Siegel Racing** · 10-23-2006, 08:07 AM

Just so people understand, we had it drop to ZERO percent wastegate at 5500 rpm on both the stock solenoid and the EBCS. Even at 0.0% wastegate duty with an EBCS (which puts more pressure on the wastegate than a stock solenoid with restrictor) it still creeps over 20.5 psi...

The EBCS made it a bit easier to have more boost down low and the same or less creep... I offered to take the EBCS off as it did not solve the problem.

This is likely the MOST boost-creep prone setup you can possibly put together. It's an '04 STi with an APS divorced DP and a large catless exhaust.

This is what I call "Terminal Mechanical Creep." I've tuned well over 150 stock-turbo STi's and maybe 5 have had true "TMC." I think at least 4 of them were divorced DP catless setups...

A light wastegate port is the only "guaranteed" way to prevent creep and I haven't personally seen one that we couldn't get back to 18+ psi after porting.

SS

WXRTSI · 10-23-2006, 09:19 AM

If this problem happens to everyone with the aps dp, then maybe it's time to buy other downpipes. That sounds like it would cut down on sum creep issues right there.

Trum1982 · 10-23-2006, 08:49 PM

i am still confused on what i should do. should i port wastegate and risk messing up turbo. try getting a true bellmouth cat. or just live with it until later down the road when i go bigger turbo.

10-21-2006, 06:40 AM	#1
Trum1982 Junior STI Driver Car: 04 WRB/Gold Location: sarasota, fl Posts: 75 Join Date: Feb 2005 Trader Rating: (0)	need help boost creep after protune ok guys i have a problem i have had so many different things said to me. i will start at the beginning. i have a cobb ap with aps tbe injen cai and walbro 255 fuel pump. i got protuned last wednesday. i was told i had terminal mechanical boost creep right at 5000 rpms my boost starts to go up instead of tapering off. now here is what i was told. i could port wastegate by the tuner, i asked other tuners and they said no way do not port the wastegate. i could try a different exhaust since the aps has a divider going into the turbo the wastgate opens and hits the divider. but the guys at agile auto says they tune cars all the time with aps with no boost creep. last option get a bigger turbo wich i plan to do but not for like a year no money right now. can someone plz help me thanks This ad is not endorsed by this member. Please register or login to hide this ad.

10-23-2006, 08:49 PM	#15
Trum1982 Junior STI Driver Car: 04 WRB/Gold Location: sarasota, fl Posts: 75 Join Date: Feb 2005 Trader Rating: (0)	i am still confused on what i should do. should i port wastegate and risk messing up turbo. try getting a true bellmouth cat. or just live with it until later down the road when i go bigger turbo. This ad is not endorsed by this member. Please register or login to hide this ad.

10-21-2006, 08:03 AM	#2
Trum1982 Junior STI Driver Car: 04 WRB/Gold Location: sarasota, fl Posts: 75 Join Date: Feb 2005 Trader Rating: (0)	guys i need some help so any one with any info would be great. i also have some data logs if anyone knows anything about tuning.

10-21-2006, 08:10 AM	#3
evilSTi7 The Hoff Fan Club, member #001 Car: 05 WRB/Gold Fav Mod: Hood Scoop Homer Location: Where ever The Hoff is! Posts: 10,278 Join Date: Jul 2004 Trader Rating: (4)	ok, well if you can find someone who has ported other stock wastegates that is certainly an option. Another option would be to get an external wastegate. that will cure your boost creep for sure, but it's expensive (probably around 600 for the parts) and you'll need to get retuned for it. Are you catless? If you are you could try swapping the aps cat onto there and that might help a little, but probably won't totally fix it.

10-21-2006, 08:35 AM	#4
crystal_Imprezav Spec C Club Car: Slow 05 STi Fav Mod: Loping Idle Location: Chewy's Garage Posts: 1,863 Join Date: Mar 2005 Trader Rating: (11)	Who was the tuner? It is pretty easy to tune out creep at higher rpm's with WGDC's and turbo dynamics. I personally would not port the wategate due to the fact that it needs to be done prefectly or you will just not hit target boost ever. The harder creep to tune out is in the mid rpm range where boost peaks and it is possible to see spikes at higher gears.

10-21-2006, 09:20 AM	#5
Trum1982 Junior STI Driver Car: 04 WRB/Gold Location: sarasota, fl Posts: 75 Join Date: Feb 2005 Trader Rating: (0)	i have no cat i am currently talking to jermey at agile i sent him some of my data logs and he said he would look at them to see what is going on. i also have a ebcs on there and that didn't help. i was told by jeremy and hill not to portwastegate. so i am kinda of stuck

10-21-2006, 09:35 AM	#6
crystal_Imprezav Spec C Club Car: Slow 05 STi Fav Mod: Loping Idle Location: Chewy's Garage Posts: 1,863 Join Date: Mar 2005 Trader Rating: (11)	The EBCS is probably the culprit. It holds boost more stable so thats probably why it continues to boost up top. It takes more fine tuning to get the boost settings correct and I am sure the Agile crew will take care of you. What is the boost rising to up top? If you post a log I could better give my opinions.

10-21-2006, 09:49 AM	#7
WXRTSI Grassroots STI Racer Car: Blue, 06 STI Fav Mod: Accessport Location: NC Posts: 586 Join Date: Aug 2006 Trader Rating: (3)	Gl with all that man. Has any1 ever experieced boost creep on stg1?

10-22-2006, 09:20 PM	#8
Trum1982 Junior STI Driver Car: 04 WRB/Gold Location: sarasota, fl Posts: 75 Join Date: Feb 2005 Trader Rating: (0)	do you guys think it might help if i changed my dp since i have a 3 aps and the dp has a divider. i was told when the wastegate opens it doesn't open all the way and it releases gas right into the divider which causes boost creep. should i change exhaust and get a bellmouth.

10-22-2006, 10:38 PM	#9
WXRTSI Grassroots STI Racer Car: Blue, 06 STI Fav Mod: Accessport Location: NC Posts: 586 Join Date: Aug 2006 Trader Rating: (3)	It's definitely worth a shot. U won't know unless u try, but from the sound of things it makes perfect sense.

10-22-2006, 11:09 PM	#10
*Tomerville* Likkle Jacob Car: '06 STI Fav Mod: AVIC D-3 Location: Too many places. Posts: 1,116 Join Date: May 2006 Trader Rating: (5)	I'm not familiar with APSs DPs, and the swappable Cat, but if you purchase a catted downpipe, and then get a retune, you could have gotten an EWG for that price, and then you are guaranteed not to get the creepies. I am catless and when its below 40, I get some creep issues in 5th gear, and only 5th gear. Since i'm going with a different turbo setup in a month or so I'm just holding out until I go EWG and Protune. Basically, i'm just saying that investing in getting rid of boost creep is largely based on your future plans and budget.

10-23-2006, 05:28 AM	#11
crystal_Imprezav Spec C Club Car: Slow 05 STi Fav Mod: Loping Idle Location: Chewy's Garage Posts: 1,863 Join Date: Mar 2005 Trader Rating: (11)	The APS DP has a wastegate divider which in its production form the extra material and angle can cause creep. Nhluhr has a write up about it somewhere and how to grind it to smoothness to eliminate the problem. Search him or search the forum to find the post.

10-23-2006, 08:07 AM	#13
Siegel Racing Authorized Vendor Car: Your STi ;) Fav Mod: Everything Location: Atlanta Posts: 1,241 Join Date: Mar 2005 Trader Rating: (2)	Just so people understand, we had it drop to ZERO percent wastegate at 5500 rpm on both the stock solenoid and the EBCS. Even at 0.0% wastegate duty with an EBCS (which puts more pressure on the wastegate than a stock solenoid with restrictor) it still creeps over 20.5 psi... The EBCS made it a bit easier to have more boost down low and the same or less creep... I offered to take the EBCS off as it did not solve the problem. This is likely the MOST boost-creep prone setup you can possibly put together. It's an '04 STi with an APS divorced DP and a large catless exhaust. This is what I call "Terminal Mechanical Creep." I've tuned well over 150 stock-turbo STi's and maybe 5 have had true "TMC." I think at least 4 of them were divorced DP catless setups... A light wastegate port is the only "guaranteed" way to prevent creep and I haven't personally seen one that we couldn't get back to 18+ psi after porting. SS

10-23-2006, 09:19 AM	#14
WXRTSI Grassroots STI Racer Car: Blue, 06 STI Fav Mod: Accessport Location: NC Posts: 586 Join Date: Aug 2006 Trader Rating: (3)	If this problem happens to everyone with the aps dp, then maybe it's time to buy other downpipes. That sounds like it would cut down on sum creep issues right there.