boost won't increase.

dannys35 · 03-11-2010, 04:54 AM

Ok. here is the problem wanted to turn up the boost on my car it tops out at 12 PSI but the boost controller is all the way open am I doing this wrong should I be closing it.On one side it has a plus sign and tells you what way to turn. On the other it has a minus sign and tells you what way to turn. I turned in the direction of the plus sign and am still only hitting 12 PSI the turbo is a t-61 and I know it should be hitting more than 12 PSI any thoughts or suggestions are appreciated is it just that the car needs to be tuned.I know that it has never been tuned and it is running off the factory ECU should I upgrade that as well.Thanks!!

btwilson86 · 03-11-2010, 07:36 AM

Where did you install your mbc at? IIRC, it should be in the vacuum line leading to the wastegate actuator

dannys35 · 03-11-2010, 05:33 PM

I am not sure were it is I bought the car with the mods on it already to tell you the truth I dont know much about cars with turbo's in general I bought it because it is one of my dream cars.

btwilson86 · 03-11-2010, 05:50 PM

Well, take a picture of the boost controller and post it on here. That way we can see what vacuum line it's attached to and see if that's the problem

dannys35 · 03-11-2010, 06:25 PM

Ok I will do that thanks

dannys35 · 03-11-2010, 07:10 PM

Ok I uploaded some pics there are a lot of things in the way I hope this helps thanks

dannys35 · 03-11-2010, 08:29 PM

The pics are in my albums section.

cre · 03-12-2010, 01:21 AM

Is it stumbling when you hit 12psi?

btwilson86 · 03-12-2010, 08:08 AM

This was sent in a PM to dannys35, but thought I'd post it here so that anyone else having a similar problem will be able to get some info from this thread:

On the front side of the turbo, towards the bottom of it there should be a round disk with a vacuum line coming out of it. This is your wastegate actuator (this controls when the wastegate opens, which regulates how high or low your turbo will spool). When routed properly, this vacuum line will have the other end of it connect to an intake hose that receives boost (don't remember where the factory one is, but it's after the turbo). What you want to do is put your mbc (manual boost controller) in this vacuum line. This way the mbc can restrict the flow of the boosted air to the wastegate actuator, causing it to open less and later, resulting in higher boost.

With that said, you should definitely check for any vacuum leaks or degrading hose couplers, etc. that can result in leaking boost. Any boost leak will cause a higher work load on the turbo, which could drastically shorten it's life. This is also important because as I understand it 12 psi is near the upper limits of the stock fuel delivery system, which means you'll start running lean and hit fuel cut

dannys35 · 03-12-2010, 04:22 PM

Yes cre it stumbles though all the boost range and if you have it in 5th gear doing 60MPH you have to down shift or it starts to shake and stumble and wont go any faster I am confused with that. I guess it may be the clutch what kind of clutch do you suggest that I get.

03-11-2010, 04:54 AM	#1
dannys35 Intake Join Date: Feb 2010 Location: Carthage NC Posts: 33	boost won't increase. Ok. here is the problem wanted to turn up the boost on my car it tops out at 12 PSI but the boost controller is all the way open am I doing this wrong should I be closing it.On one side it has a plus sign and tells you what way to turn. On the other it has a minus sign and tells you what way to turn. I turned in the direction of the plus sign and am still only hitting 12 PSI the turbo is a t-61 and I know it should be hitting more than 12 PSI any thoughts or suggestions are appreciated is it just that the car needs to be tuned.I know that it has never been tuned and it is running off the factory ECU should I upgrade that as well.Thanks!! Last edited by dannys35; 03-11-2010 at 04:56 AM.

03-11-2010, 07:36 AM	#2
btwilson86 Super Moderator Join Date: May 2007 Location: Billings, Montana Posts: 1,034	Where did you install your mbc at? IIRC, it should be in the vacuum line leading to the wastegate actuator __________________ 1989 7MGTE R154 Targa Top White Package w/Blue Interior Driftmotion 57trim CT26, Upgraded Intercooler, 2.25" Hard Pipes, 3" Turbo Back Exhaust with Test Pipe, HKS VPC w/GM 3 bar MAP sensor, APEXi S-AFC, Walbro 255lph fuel pump, ProSport EVO Series Boost / Fuel Pressure / AFR gauges, Lotek a Pillar Gauge Pod, HKS Type 0 Turbo Timer, Eibach Lowering Springs, Tokico Illumina II TEMS struts, custom powder coated Motegi Racing TrakLite wheels

03-11-2010, 05:50 PM	#4
btwilson86 Super Moderator Join Date: May 2007 Location: Billings, Montana Posts: 1,034	Well, take a picture of the boost controller and post it on here. That way we can see what vacuum line it's attached to and see if that's the problem __________________ 1989 7MGTE R154 Targa Top White Package w/Blue Interior Driftmotion 57trim CT26, Upgraded Intercooler, 2.25" Hard Pipes, 3" Turbo Back Exhaust with Test Pipe, HKS VPC w/GM 3 bar MAP sensor, APEXi S-AFC, Walbro 255lph fuel pump, ProSport EVO Series Boost / Fuel Pressure / AFR gauges, Lotek a Pillar Gauge Pod, HKS Type 0 Turbo Timer, Eibach Lowering Springs, Tokico Illumina II TEMS struts, custom powder coated Motegi Racing TrakLite wheels

03-12-2010, 01:21 AM	#8
cre Toyota Racing Development Join Date: Apr 2007 Posts: 5,038	Is it stumbling when you hit 12psi? __________________ If something breaks or you need to contact a member of the administration please post HERE. Unless it's a private or administration matter please post it on the forum. It benefits no one else if car related questions aren't posted for future users and takes away from the time I'm able to spend helping on the rest of the forum. If you're so inclined I'm always more than happy to accept tips via PayPal. Tip Jar --->

03-12-2010, 08:08 AM	#9
btwilson86 Super Moderator Join Date: May 2007 Location: Billings, Montana Posts: 1,034	This was sent in a PM to dannys35, but thought I'd post it here so that anyone else having a similar problem will be able to get some info from this thread: On the front side of the turbo, towards the bottom of it there should be a round disk with a vacuum line coming out of it. This is your wastegate actuator (this controls when the wastegate opens, which regulates how high or low your turbo will spool). When routed properly, this vacuum line will have the other end of it connect to an intake hose that receives boost (don't remember where the factory one is, but it's after the turbo). What you want to do is put your mbc (manual boost controller) in this vacuum line. This way the mbc can restrict the flow of the boosted air to the wastegate actuator, causing it to open less and later, resulting in higher boost. With that said, you should definitely check for any vacuum leaks or degrading hose couplers, etc. that can result in leaking boost. Any boost leak will cause a higher work load on the turbo, which could drastically shorten it's life. This is also important because as I understand it 12 psi is near the upper limits of the stock fuel delivery system, which means you'll start running lean and hit fuel cut __________________ 1989 7MGTE R154 Targa Top White Package w/Blue Interior Driftmotion 57trim CT26, Upgraded Intercooler, 2.25" Hard Pipes, 3" Turbo Back Exhaust with Test Pipe, HKS VPC w/GM 3 bar MAP sensor, APEXi S-AFC, Walbro 255lph fuel pump, ProSport EVO Series Boost / Fuel Pressure / AFR gauges, Lotek a Pillar Gauge Pod, HKS Type 0 Turbo Timer, Eibach Lowering Springs, Tokico Illumina II TEMS struts, custom powder coated Motegi Racing TrakLite wheels

03-11-2010, 05:33 PM	#3
dannys35 Intake Join Date: Feb 2010 Location: Carthage NC Posts: 33	I am not sure were it is I bought the car with the mods on it already to tell you the truth I dont know much about cars with turbo's in general I bought it because it is one of my dream cars.

03-11-2010, 06:25 PM	#5
dannys35 Intake Join Date: Feb 2010 Location: Carthage NC Posts: 33	Ok I will do that thanks

03-11-2010, 07:10 PM	#6
dannys35 Intake Join Date: Feb 2010 Location: Carthage NC Posts: 33	Ok I uploaded some pics there are a lot of things in the way I hope this helps thanks

03-11-2010, 08:29 PM	#7
dannys35 Intake Join Date: Feb 2010 Location: Carthage NC Posts: 33	The pics are in my albums section.

03-12-2010, 04:22 PM	#10
dannys35 Intake Join Date: Feb 2010 Location: Carthage NC Posts: 33	Yes cre it stumbles though all the boost range and if you have it in 5th gear doing 60MPH you have to down shift or it starts to shake and stumble and wont go any faster I am confused with that. I guess it may be the clutch what kind of clutch do you suggest that I get.

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