Stock Fuel System Potential?

[RyanSinibaldi]

i know its a terrible idea, so spare me the "dont do that's" and "do it the right way"

but how much boost can a run on a totally stock fuel system and are there any tricks i can do to run a little more boost?

i have a 1991 coupe w/ an automatic and i have a manifold and a t28 turbo

i have another KA that sits so if this one blows, it doesnt bother me...it will give me a reason to do a 5-speed swap

one more question, how much horsepower can automatics hold? and how are they when boosted...thank in advance

-ryan

[Craving4Boost]

i wont give you a dont do that or a do it the right way...but ill give ya a "Search"

[Structure240sx]

"dont do that's" and "do it the right way"

get a $100 fmu at least and a fuel pump or hardwire your stock pump at the very least, if you arent worried about blowing it up. just think of the time, work, and money you will save by doing it right

stock auto transmission is good uotp about 400rwhp, limits have actually been found yet

[Import_Ant]

hot offa' page 1

zerothread?id=134635

good read

[RyanSinibaldi]

so do you guys think i could just get a fuel pump, maybe an a/f ratio just incase to monitor things, and then run 6psi daily making sure i use 93 octane?

[Craving4Boost]

you need a FMU...the upgraded fuel pump is just to ensure the pressure the FMU is demanding is withheld

[Import_Ant]

so do you guys think i could just get a fuel pump, maybe an a/f ratio just incase to monitor things, and then run 6psi daily making sure i use 93 octane?

it's not about how much boost. it's about 1) the efficency range of the turbo you're using and 2) power output of the motor. saying 6psi is worthless if we don't know what turbo you are using and other supporting mods. 6psig might be ok or it might not.

in the thread I linked it covered that in a fair amount of detail. the jist is, if you are keeping your turbo within its efficency range and keeping the motor's power output within the injectors capacity you'll be fine. Ckwik posted some math showing the stock injectors to be capable of ~190 hp

keep your motor below that in terms of power and the turbo within its range of efficency and you should be ok.

[fabio420]

Ok, this is something i know, because i tried it myself. You can boost 6 psi on a t25 on stock injectors. With a 8:1 fmu I ran my stock injectors to 220 hp at 12psi. I know alot of people will call me a liar for this, but I know what I did, and I have a dyno sheet to prove it. You wanted a no "don't and do's" so this is it. I know these numbers to be true because I ran them. I still have that fmu, if you want it. I've moved on to bigger injectors.But it can be done. although not recommende for long term, or high horses.

[sunnys14]

i ran a 12:1 FMU with stock injectors@ 8psi on my t04e. ran mad rich but still boosted fine. like people are saying, i dont recommend this for a long term setup.

[Craving4Boost]

should have gotten a bleeder valve to let out some of that pressure