Wtf??

MK34me · 06-25-2010, 08:43 PM

I just picked up a '91 Turbo. It's a bit of a basketcase but I have made great strides!! Here's my dilema. The car has a aftermarket turbo, a T-65 I believe and when I hit it the turbo spools up and right about the time I should be waving bye bye to the punk in the lowered Civic with the neon green hub caps, (no, seriously) the turbo bogs out. It is roughly at 4000-4500 rpms. Every shift, every time I punch it!!!!
Vacuum lines are all good to go. Can it be the external wastegate on the turbo? I was told it could be my injectors, that they aren't supplying enough fuel but what does fuel have to do with spool? I thought it was the airmass, quantuty & temp that made the dif.
It's my first turbo, heck my first Supra and I am not that savvy yet.

Any help would be greatly appreciated.

Mike

btwilson86 · 06-28-2010, 05:19 PM

How much boost are you running when it cuts out?

It sounds to me like someone slapped a Big @$$ turbo on the car without upgrading the fuel system, and you're now hitting fuel cut.

What your fuel delivery has to do with spool is this: your car is constantly trying to maintain a safe air:fuel mixture, while you're spooling you're cramming a ton of air into your engine, so the computer needs to cram a bunch of fuel in there to even it out. If the amount of air exceeds the required amount of fuel, the computer cuts the fuel delivery to protect the engine from running lean and BAM! Fuel Cut.

Green7mgte · 06-28-2010, 08:59 PM

ye sounds like fuel cut.. you can go acouple different routs here..
first I would suggest getting a wideband monitor so you can see what your air to fuel ratio is..

then either upgrade to 550cc injectors (about $400) or a cheaper but more technical and probably not as efficient rout would be to get a safc (super air flow controller) with that item you can manually control how much fuel to air your putting out.. 50% either direction. (about $200)

I have an safc2. if i could go back I would get an safc NEO.
I used it in conjunction with my upgraded Lex afm. I can correct my air flow 50% either direction through the rpm's to maintain a good mixutre. this PIGGYBACK system is acceptable but the more reliable and non tuner way would be to get a STANDALONE witch would be Upgrading to 550CC injectors and getting a walbro 225 fuel pump and upgrading your fuel pressure regulator

06-25-2010, 08:43 PM	#1
MK34me Stock Join Date: Apr 2010 Location: Oceanside, CA Posts: 5	Wtf?? I just picked up a '91 Turbo. It's a bit of a basketcase but I have made great strides!! Here's my dilema. The car has a aftermarket turbo, a T-65 I believe and when I hit it the turbo spools up and right about the time I should be waving bye bye to the punk in the lowered Civic with the neon green hub caps, (no, seriously) the turbo bogs out. It is roughly at 4000-4500 rpms. Every shift, every time I punch it!!!! Vacuum lines are all good to go. Can it be the external wastegate on the turbo? I was told it could be my injectors, that they aren't supplying enough fuel but what does fuel have to do with spool? I thought it was the airmass, quantuty & temp that made the dif. It's my first turbo, heck my first Supra and I am not that savvy yet. Any help would be greatly appreciated. Mike

06-28-2010, 05:19 PM	#2
btwilson86 Super Moderator Join Date: May 2007 Location: Billings, Montana Posts: 1,034	How much boost are you running when it cuts out? It sounds to me like someone slapped a Big @$$ turbo on the car without upgrading the fuel system, and you're now hitting fuel cut. What your fuel delivery has to do with spool is this: your car is constantly trying to maintain a safe air:fuel mixture, while you're spooling you're cramming a ton of air into your engine, so the computer needs to cram a bunch of fuel in there to even it out. If the amount of air exceeds the required amount of fuel, the computer cuts the fuel delivery to protect the engine from running lean and BAM! 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

06-28-2010, 08:59 PM	#3
Green7mgte Supra Forum Moderator Join Date: Nov 2009 Location: Green-Ohio Posts: 1,297	ye sounds like fuel cut.. you can go acouple different routs here.. first I would suggest getting a wideband monitor so you can see what your air to fuel ratio is.. then either upgrade to 550cc injectors (about $400) or a cheaper but more technical and probably not as efficient rout would be to get a safc (super air flow controller) with that item you can manually control how much fuel to air your putting out.. 50% either direction. (about $200) I have an safc2. if i could go back I would get an safc NEO. I used it in conjunction with my upgraded Lex afm. I can correct my air flow 50% either direction through the rpm's to maintain a good mixutre. this PIGGYBACK system is acceptable but the more reliable and non tuner way would be to get a STANDALONE witch would be Upgrading to 550CC injectors and getting a walbro 225 fuel pump and upgrading your fuel pressure regulator __________________ 92 Ma71 7mGTE Auto. SafcII Supra FAQ Supra MKIII FAQ Classified Section guidelines :