boost issue

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boost issue

Postby Rallly » Sun Oct 11, 2015 12:30 am

My stock st185 boosts only to 8psi in 2nd-5th gear and tappers down if I hold the throttle position. Boost leak?
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Rallly
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Re: boost issue

Postby zaluss » Sun Oct 11, 2015 1:35 am

Rallly wrote:My stock st185 boosts only to 8psi in 2nd-5th gear and tappers down if I hold the throttle position. Boost leak?


Check the TVSV? http://www.turbocelica.nl/howto-tvsv.htm
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Re: boost issue

Postby Rallly » Sun Oct 11, 2015 4:06 am

According to the "How too" it will keep my boost at 50kpa instead of 70kpa. I don't want to lower my boost?


zaluss wrote:
Rallly wrote:My stock st185 boosts only to 8psi in 2nd-5th gear and tappers down if I hold the throttle position. Boost leak?


Check the TVSV? http://www.turbocelica.nl/howto-tvsv.htm
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Re: boost issue

Postby underscore » Sun Oct 11, 2015 4:37 am

Right, so if it's broken you'll only get 50kPa or ~8psi.
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Re: boost issue

Postby Rallly » Sun Oct 11, 2015 12:39 pm

underscore wrote:Right, so if it's broken you'll only get 50kPa or ~8psi.



If it's broke do I need to replace the actuator?
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Re: boost issue

Postby Rallly » Sun Oct 11, 2015 1:02 pm

underscore wrote:Right, so if it's broken you'll only get 50kPa or ~8psi.



I'm already only getting 8psi, so how will I know if it's broken? sorry, I guess I think I'm missing something.
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Re: boost issue

Postby zaluss » Sun Oct 11, 2015 2:57 pm

Rallly wrote:
underscore wrote:Right, so if it's broken you'll only get 50kPa or ~8psi.



I'm already only getting 8psi, so how will I know if it's broken? sorry, I guess I think I'm missing something.


For Gen2 3SGTE, the TVSV is nothing more than a basic safety device that limits you to a low boost (8psi) setting until the engine is warmed up. Its a factory boost controller.

Requirements for higher boost with the TVSV:

1) coolant temp >160F
2) intake air temp > 32F
3) positive manifold pressure

It may not be allowing you to go into high boost because there is a vacuum leak or issue with the TVSV itself.

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Re: boost issue

Postby Rallly » Sun Oct 11, 2015 3:39 pm

I did in fact have a couple boost leaks. I just fixed them in hopes that all would be good when I went for a drive. Just came back, still only able to hit 0.6Bar(8~psi). What can I check next ? Better yet, is it possible to bypass the tvsv all together and have full boost potential at all times?
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Re: boost issue

Postby zaluss » Sun Oct 11, 2015 8:20 pm

Rallly wrote:I did in fact have a couple boost leaks. I just fixed them in hopes that all would be good when I went for a drive. Just came back, still only able to hit 0.6Bar(8~psi). What can I check next ? Better yet, is it possible to bypass the tvsv all together and have full boost potential at all times?


Yes. Install a manual or electronic boost controller to bypass the tvsv.

http://twosrus.com/catalog/product_info ... ucts_id=62

http://www.twosrus.com/Articles/Install ... ctions.PDF

Pretty simple. You block off the connection between the wastegate to the tvsv and plug the vacuum hose on the tvsv then add the boost controller between the turbo and wastegate.
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Re: boost issue

Postby Rallly » Mon Oct 12, 2015 6:53 am

Before I go ahead and order that MBC, I just want to be sure I'm good to go and not just throwing money away. If my T-vsv or actuator was fried( stuck at.8~psi) would this MBC still allow my turbo to boost to 14psi?



zaluss wrote:
Rallly wrote:I did in fact have a couple boost leaks. I just fixed them in hopes that all would be good when I went for a drive. Just came back, still only able to hit 0.6Bar(8~psi). What can I check next ? Better yet, is it possible to bypass the tvsv all together and have full boost potential at all times?


Yes. Install a manual or electronic boost controller to bypass the tvsv.

http://twosrus.com/catalog/product_info ... ucts_id=62

http://www.twosrus.com/Articles/Install ... ctions.PDF

Pretty simple. You block off the connection between the wastegate to the tvsv and plug the vacuum hose on the tvsv then add the boost controller between the turbo and wastegate.
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Re: boost issue

Postby zaluss » Mon Oct 12, 2015 10:51 am

Rallly wrote:Before I go ahead and order that MBC, I just want to be sure I'm good to go and not just throwing money away. If my T-vsv or actuator was fried( stuck at.8~psi) would this MBC still allow my turbo to boost to 14psi?


Yes because you would be bypassing it completely.
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Re: boost issue

Postby Rallly » Mon Oct 12, 2015 1:29 pm

zaluss wrote:
Rallly wrote:Before I go ahead and order that MBC, I just want to be sure I'm good to go and not just throwing money away. If my T-vsv or actuator was fried( stuck at.8~psi) would this MBC still allow my turbo to boost to 14psi?


Yes because you would be bypassing it completely.




Okay thank you :)
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Re: boost issue

Postby underscore » Tue Oct 13, 2015 4:35 am

I'd suggest borrowing one from someone local to you first if you can, that way you can be sure that's the issue before spending any money.
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Re: boost issue

Postby Rallly » Wed Nov 18, 2015 3:35 pm

Any other MBC you guys can recommend me? I'm in Canada and can't justify the super high shipping price on the tworus mbc. Also what is the max psi I should raise it to with my stock turbo(ct26b I think)
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Re: boost issue

Postby underscore » Tue Nov 24, 2015 2:59 am

You can make one yourself with hardware store parts for cheap, max boost with the stock ECU is 14.7 psi I believe, so keep it below 13ish to be safe. Obviously it's dependent on the condition of your car as well.
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