why am i hitting fuel cut ?

[mk3supra978]

people say i can turn it up safely on stock turbo stock fuel system to like 12lbs i have max redline intercooler kit 3 inch hks exhaust hsp intake kit how come i cannot boost to atleast 10-11lbs ? i set at 9lbs right now but if i turn it up just a little it hits fuel cut WHY ? please help me......

 

[dubsupra209]

no codes...? im at 9psi with my 57trim

 

[mk3supra978]

no codes.. i wanna run atleast 10-11lbs but it wont let me no leaks no nothing but when i turn it up fuel cut kicks in

 

[Moy]

what temperature are you doing this at? colder air is dense, meaning you need less air to hit FC

 

[mk3supra978]

it was pretty cold out...so your saying cold air makes it go fuel cut ? O_O

 

[JStoked]

Lexus maf installed?

 

[mk3supra978]

no still got the stock maf........

 

[IJ.]

Fuel cut ISN'T Pressure it's Volume, there's a difference...

 

[mk3supra978]

i still dont get it why am i hitting fuel cut if its safely to turn up to 10-11lbs on stock fuel system n stock turbo ?

 

[IJ.]

xx flow through the engine will trigger fuel cut, whatever you've done is obviously enough to get there, might be cold dense air helping or a leak in the IC piping you haven't found.

 

[JStoked]

bro i have a Lexus maf ill sell for 50 bucks shipped.Also your going to need 550 or better injectors. and so on. more boost equals more upgrades.

 

[mk3supra978]

but i dont wanna upgrade people keep saying that its safe to boost up to 12lbs on stock fuel system n stock turbo so i was just wondering why i hit fuel cut...but ill check into that intercooler pipe leaks

 

[Moy]

bro i have a Lexus maf ill sell for 50 bucks shipped.Also your going to need 550 or better injectors. and so on. more boost equals more upgrades.

and then you need to drill out the j-tube or bypass it, install a higher flowing fuel pump, and for safety an adjustable fuel pressure regulator.

sure you can go lex maf + 550's, but if the O2 is reading lean lean lean the ECU is going to say "add fuel add add add" and if that happens it'll burn out the stock pump from running 100+% all the time

 

[radiod]

if that happens it'll burn out the stock pump from running 100+% all the time

Correct me if I'm wrong (this is an honest I don't know question), but doesn't the fuel pump run 100% all the time anyways? I know there's a 9V/12V switch, but beyond that, it's either on or off I thought. That's what a pressure regulator is for, isn't it?

As for the OP, fuel cut is affected by air temp, humidity, and your elevation. Generally the cooler it is and the closer to sea level, the lower fuel cut will be. As it was mentioned earlier, fuel cut is by volume, not by pressure. If you're pressurizing your larger intercooler/piping with the same pressure, it's more volume as well, further lowering fuel cut. I have 2.5" hard pipes and a 57-trim and on a cold day, I hit fuel cut a touch over 10psi. On a hot summer day, I hit 11-12 before it cuts.