factory boost for 90 alltrac

[V_boy]

anyone know?

[boosty]

Same turbo as the MKIII Supra, right? CT26? If so, then my guess is 6 psi.

[benyl]

The Toyota ECU (computer) has a built in protection to keep the turbo from preventing damage to the motor in the case of an over boost. An over boost would be when the turbo pressure limiting system failed, causing the turbo to start making unlimited boost. If this were allowed to continue, your motor would shortly be broken. The Toyota ECU uses a pressure sensor to detect maximum boost. Maximum boost in this case is 12 psi for ST165 and ST185, and 17 psi for ST185RC/ST205. If this amount is detected, the fuel will stop being sprayed into the engine momentarily to prevent further combustion. When driving this appears to be a sudden loss of power, causing you to fly towards the dash. It is almost the same effect as slamming on the brakes. In some cases the check engine light will flash as well, until the car is turned off. This is a good safety feature, but if you are trying to run higher boost on purpose, it can be a road block. There are several devices available to remove this fuel cut (or raise it to a higher level). See the Modifications FAQ for more information.

http://www.alltrac.net/FAQ.html

[Redlyne_mr2]

Depends on air temp and condition of the engine but you can expect anything from 6-8psi

[benyl]

http://www.alltrac.net/specs/st165USAspecs.html


Actually only 10.2 psi

[Redlyne_mr2]

The Toyota ECU (computer) has a built in protection to keep the turbo from preventing damage to the motor in the case of an over boost. An over boost would be when the turbo pressure limiting system failed, causing the turbo to start making unlimited boost. If this were allowed to continue, your motor would shortly be broken. The Toyota ECU uses a pressure sensor to detect maximum boost. Maximum boost in this case is 12 psi for ST165 and ST185, and 17 psi for ST185RC/ST205. If this amount is detected, the fuel will stop being sprayed into the engine momentarily to prevent further combustion. When driving this appears to be a sudden loss of power, causing you to fly towards the dash. It is almost the same effect as slamming on the brakes. In some cases the check engine light will flash as well, until the car is turned off. This is a good safety feature, but if you are trying to run higher boost on purpose, it can be a road block. There are several devices available to remove this fuel cut (or raise it to a higher level). See the Modifications FAQ for more information.

That information discloses the fuel cut and not the factory boost levels

[Redlyne_mr2]

Originally posted by benyl
http://www.alltrac.net/specs/st165USAspecs.html


Actually only 10.2 psi
Im not sure where they got that number from but it is wrong
Edit: I just noticed that the engine alltrac.net was describing was the first gen 3sgte st165 and was not as efficient or powerful as the 3sgte in the st185, the celica in question

[benyl]

Originally posted by Redlyne_mr2

Im not sure where they got that number from but it is wrong

My bad, that is for the older all-trac. The newer one isn't posted.

If you click on the link and scroll down to the turbo section, it is there... but not for the 1990 celica.

[LancerShelby]

Originally posted by V_boy
anyone know?
Not enough