Now, i just had my headgasket done. I had a slight headgasket leak and i can tell you now what a difference. Now, i seem to be hitting fuel cut quite early at around 10-12psi. I bought an hks fuel cut defenser and i am a little hesitant right now to install it, before i get some information on it. Now, i am assuming the reason im hitting fuel cut is because my ecu is recognizing im boosting more than i should or is it because im running lean? Secondly, if i do install the fcd will that just stop my fuel cut and cause my motor to be constantly running lean when im boosting more then the stock boost value. Someone help me out please.
fcd question
- Thread starter huntin5L
- Start date
Depends on what FCD you picked up. Some of them just cap the signal, making fuel cut never happen - some of them scale the signal, moving fuel cut to a higher boost level. The former is junk, I wouldn't put it anywhere near my car, the latter is ok, but even so I'd spend a bit more money and buy a MAFT so it's tuneable. (Actually, I did just this... 
)
10-12 seems a little low, but could be correct - check for any boost leaks.
)10-12 seems a little low, but could be correct - check for any boost leaks.
ok
with the HKS FCD
here is what i recommend.
Get all necessary tools
Get HKS FCD.
Smash HKS FCS with said tools.
Done.
Do not install the HKS FCD. It is not a viable option. FCD is there to PROTECT your motor.
with the HKS FCD
here is what i recommend.
Get all necessary tools
Get HKS FCD.
Smash HKS FCS with said tools.
Done.
Do not install the HKS FCD. It is not a viable option. FCD is there to PROTECT your motor.
LOL nicely put. haha..What are you guys hitting fuel cut at, assuming your running the stock turbo. And if im hitting fuel cut is it because im running lean? Anywho here is the fcd i bought by hks. http://www.supraforums.com/forum/showthread.php?t=324075
well you will until you blow the motor then you will not be running anymore instead
so do not install it!!
so do not install it!!
well no
you can go
maft
Maft-pro
standalone (Megasquirt, AEM et al)
Greddy Emanage
so many options. BUT the motor wont last without the appropiate SUPPORTING upgrades (bigger injectors, walbro fuel pump)
you can go
maft
Maft-pro
standalone (Megasquirt, AEM et al)
Greddy Emanage
so many options. BUT the motor wont last without the appropiate SUPPORTING upgrades (bigger injectors, walbro fuel pump)
no
absolutely ZERO FCD's. Once again and please understand this.
Fuel cut is there to prevent boost happy driver from blowing the motor. Understand now?
absolutely ZERO FCD's. Once again and please understand this.
Fuel cut is there to prevent boost happy driver from blowing the motor. Understand now?
the answer everyone loves
It depends.
All MKIII supra are different
in one supra you might hit 11 psi and then Fuel cut and another supra you might get 15psi before Fuel cut. Also weather affects Fuel cut. So many variables.
It depends.
All MKIII supra are different
in one supra you might hit 11 psi and then Fuel cut and another supra you might get 15psi before Fuel cut. Also weather affects Fuel cut. So many variables.
FCO is not boost dependant, it's rpm/Karmann Hz dependant.
The best way to get "around" FCO is to get a fuel computer of some sort.
Just pulling the fuel that needs to be pulled to run in the 11.5 range will raise FCO a few psi on any given day (versus the same barometric pressure, temp, moisture content, etc)
The better way is to install bigger injectors, and scale the signal. This is done by a lexus and 550s, or with a maft, Fcon, VPC, etc...
We've tried the Lexus upgrade, and it was ok. It ran similarly as before, but I wouldn't expect it to run perfectly.
We then learned of the newly developed for the supra MAFT. We bought it, set the base settings to make the car run like stock, and it ran much better than it did with the lexus. After hitting the dyno, it runs much more consistantly than it did with the lexus.
One thing to keep in mind is that you never want to pull more than 15% fuel with any computer. This also means you don't wan't to scale the afm output to the ecu by more than some set amount.
The reason is because the more fuel you pull, the more timing you add, so pulling 15% fuel may lead to an increase in timing by a similar amount. This will lead to detonation which ruins motors.
That's called 23% timing pulled @ 21 psi with forged pistons. Actually, ross pistons, which are supposed to be the strongest.
FCO is in the system to keep the above from happening. THis means that if you intend to bypass it, you better cover all of your bases and know exactly what you're doing.
-Jake
The best way to get "around" FCO is to get a fuel computer of some sort.
Just pulling the fuel that needs to be pulled to run in the 11.5 range will raise FCO a few psi on any given day (versus the same barometric pressure, temp, moisture content, etc)
The better way is to install bigger injectors, and scale the signal. This is done by a lexus and 550s, or with a maft, Fcon, VPC, etc...
We've tried the Lexus upgrade, and it was ok. It ran similarly as before, but I wouldn't expect it to run perfectly.
We then learned of the newly developed for the supra MAFT. We bought it, set the base settings to make the car run like stock, and it ran much better than it did with the lexus. After hitting the dyno, it runs much more consistantly than it did with the lexus.
One thing to keep in mind is that you never want to pull more than 15% fuel with any computer. This also means you don't wan't to scale the afm output to the ecu by more than some set amount.
The reason is because the more fuel you pull, the more timing you add, so pulling 15% fuel may lead to an increase in timing by a similar amount. This will lead to detonation which ruins motors.
That's called 23% timing pulled @ 21 psi with forged pistons. Actually, ross pistons, which are supposed to be the strongest.
FCO is in the system to keep the above from happening. THis means that if you intend to bypass it, you better cover all of your bases and know exactly what you're doing.
-Jake