turb boost increase every gear

john_lauj · 09-26-2010, 08:05 PM

this is a very weird boosting that i have. 1st gear it wont be boosting 4 lbs. 2nd gear will boost anywhere from 6-8 lbs. 3rd gear i dont know cause its way above 8 lbs. then 4th gear i get fuel cut so im guesting its pretty high boosting on 4th. same goes with 5th gear. any one has an idea wats causeing that to happen??

89ST · 09-28-2010, 09:06 PM

boost controller installed?

Boost is dependent on load right. my car also will not boost as high in first or second as it will in higher gears. i do have a manual boost controller installed though.

So it's very possible that your car when at full throttle in first only produces enough load to build roughly 4psi. but let me know if you have a BC installed or not.

hope that helps

john_lauj · 09-29-2010, 01:52 AM

no i have nothing installed.. it boost 4-6 lb on 1st gear. if im correct it should only be boosting 4. wat really gets me is i get fuel cut. that means im boosting anywhere from 12-15 psi. with a ls 400 i dont get no fuel cut.

Travis89Turbo · 09-29-2010, 02:08 AM

U didn't specify what engine u have. so I'm assuming its a 7mgte.
Standard boost is 5-7psi. Fuel cut around 10-12psi

Check your vacumm line from the turbo to the wastegate. It just a Lil guy... if it is good then unbolt your wastegate and see if u can manually actuate it freely. If it binds up then its bad. There is a spring so it will have tension. If its free and everything else is good then u have a bad diaphragm in the wastegate causing pressure to leak there for not opening the actuater at the proper psi...

09-26-2010, 08:05 PM	#1
john_lauj Stock Join Date: Mar 2010 Location: frresno Posts: 20	turb boost increase every gear this is a very weird boosting that i have. 1st gear it wont be boosting 4 lbs. 2nd gear will boost anywhere from 6-8 lbs. 3rd gear i dont know cause its way above 8 lbs. then 4th gear i get fuel cut so im guesting its pretty high boosting on 4th. same goes with 5th gear. any one has an idea wats causeing that to happen??

09-29-2010, 02:08 AM	#4
Travis89Turbo 12psi boost Join Date: Jul 2010 Location: Utah Posts: 332	U didn't specify what engine u have. so I'm assuming its a 7mgte. Standard boost is 5-7psi. Fuel cut around 10-12psi Check your vacumm line from the turbo to the wastegate. It just a Lil guy... if it is good then unbolt your wastegate and see if u can manually actuate it freely. If it binds up then its bad. There is a spring so it will have tension. If its free and everything else is good then u have a bad diaphragm in the wastegate causing pressure to leak there for not opening the actuater at the proper psi... __________________ 1995 Toyota Supra SE 71k miles. Master power T70 stock 2jzge 1989 Toyota Supra. 1jzgte swap 5 speed of course.. Driftmotion 60-1 single turbo kit. Cxracing FMIC. 2jz 550cc injectors... soon to come..... EMS Stinger. BC 264 cams 680cc injectors Spec stage 4 clutch and A LOT of boost!------SOLD 1999 Ford F350 diesel 2004 Jaguar XJR Supercharged If it hasnt broke you haven pushed it hard enough!!

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09-28-2010, 09:06 PM	#2
89ST Intake Join Date: Sep 2010 Location: Hamilton Ontario Posts: 40	boost controller installed? Boost is dependent on load right. my car also will not boost as high in first or second as it will in higher gears. i do have a manual boost controller installed though. So it's very possible that your car when at full throttle in first only produces enough load to build roughly 4psi. but let me know if you have a BC installed or not. hope that helps

09-29-2010, 01:52 AM	#3
john_lauj Stock Join Date: Mar 2010 Location: frresno Posts: 20	no i have nothing installed.. it boost 4-6 lb on 1st gear. if im correct it should only be boosting 4. wat really gets me is i get fuel cut. that means im boosting anywhere from 12-15 psi. with a ls 400 i dont get no fuel cut.