Fuel set-up

[chad_KAT]

Useing a Z32 maf, and a SAFCII, with phat ka-t's fuel system(550cc injectors)

Would that be too much for a safc II and if not how much power could this setup handel or what would a safe boost be?

[hannibal]

SAFC can handle the injectors (up to 2x stock size)350whp should be reachable with 550cc (50lb) injectors.

[chad_KAT]

oh ok, i rather use the safc then the aem ems becasue it will save me lots of money and this is my first turbo set-up so i need to calm down and start slow.

whats the BIGGEST the safc can handle....not sure on the stock size 270cc or somthing???

[Craving4Boost]

50% increase of your stock

[:: orion ::]

...and fuel is only half of tuning.

No matter how much injector you can add, you'll still blow the motor with a stock ECU when you start pushing past the ~250rwhp barrier...WAY too much timing advance.

So if I were you (and I was once)...realize that until you're ready to spend some real cash on engine managment (AEM EMS, or JWT...or "Enthalpy" tune if it's available for you), you're limited to 250rwhp or less.

Now, with that said...a set of SR20 370cc injectors will get you to about ~250rwhp safely...and the stock MAF will max out right about there as well.

And with your base timing retarded a couple degrees, you could have a nice, safe, reliable setup...maybe ~8psi from a standard T3/T4, and just under ~250rwhp.

...

So even though an S-AFC can handle injectors twice as big as stock...your motor can't handle the HP that those injectors would be needed for with a stock ECU.

- Brian

[Structure240sx]

50% increase of your stock

this is the incorrect way of saying it. the way you say it means that you can only handle 50% more than stock injectors which would be 405cc.

the safc can trim down 50% of whatever injector you run. so a 550cc injector will be trimmed down to 275cc, a 740cc injector will be trimmed down to 370cc and so on. the point it to be able to trim down enough to make it like the injector the ecu is programmed for.

[chad_KAT]

well i plan on starting out at 12-14 psi. but i KNOW i want to go higher. im just having trouble on what injectors i should choose and if the safc will be good enough for what i need it to do.

~chad

[fiznat]

What Brian is saying Chad is that you need timing control as well. There is no sense in going as big as possible with injectors on the SAFC if your timing is not up to it. 12-14 psi is too much on just fuel alone. Look into the MSD BTM perhaps, or maybe just switching over to an emanage or something like that.

That said, look at what structure said about how the S-AFC works with injector size. Also, check out our injector spreadsheet (the first stickey on the board), 2nd post. 12-14psi is a lot to start out with... I'd say around there, you are getting very close to the limits of what a SAFC type system can handle.... I would start exploring other options, especially if you expect the car to be able to accommodate your desire to increase the boost even further.

[chad_KAT]

Well i been reading on the e manage and im thinking on going that very rout...its going to be about 550 for the harnesses and software for my laptop. does that sound right....and would you guys recomend useing the timming settings with the e manage or go another route for the timming?

[Structure240sx]

thats the benefit of the emanage is that you can control timing, kinda wish i went with one instead of the safc

[Craving4Boost]

sorry struct. i got lazy on my explanation lol....

i know how to use it though! no offense to you seeing as you taught me how to use it and all