Ok so my FMU setup is proving to be just about a headache. So i'm starting to do the research about tuning with upgraded injectors for boost.

I'm either going with 370cc RC injectors, or stock 440cc WRX injectors as an upgrade. So without any kind of tuning i will be running super rich.

So, i figured this would be a good thread to get some helpful info from you guys as to what you use, and what would be recommended. I dont want anyone bashing other products, or incessantly pitching their sponsored products, just some pros and cons of their setup and other setups alike.

Ok so heres what i want. I am going to be running no more than 8 or 9psi with a AFR no higher than around 11.5 at full boost for safety vs power. I want to retain full driveability (this is my daily driver so i dont want a car that will bog down when i jump on the gas) and i dont want a sh*tty idle or anything either. I also want something that is fairly easy to tune myself without having to go through an insane learning curve.

I understand the basics of tuning, i understand what to shoot for and what not to shoot for, and i understand the basics of what each option is (RRM piggy, emanage, safc).

So what do you guys recommend? I was looking at the SAFC since A) a bunch of people are using it full time, B) it is easy to understand and change on the fly C) it doesnt require any extensive program usage or knowledge of the finer things that the ecu does. I just cant understand how i can change the curves enough during partial throttle and idle to compensate for the larger injectors. I know between the ECU and the O2 sensor the stock ECU will pull back fuel delivery a lot since it is sensing a super rich condition, but will it pull it back enough where i can adjust within the +/- 3% threshold on closed loop tuning? Open loop doesnt seem to be an issue since its just basically all in control of the hi throttle maps and i can just scale back fuel delivery by as much as i need to hit my desired afr.

I am close to deciding on the SAFC (probably neo to try it out) as long as someone can explain and reassure me that between the ecu/o2 sensor leaning out the curves due to the rich condition to target the 14.7 AFR and the fine adjustments i can make with the safc, i can nail in a comfortable stock idle and low throttle feel. I DO NOT want to sacrifice driveability for power. Theres no point

 

I know Z_Lancer_Man was/is running WRX 440 injectors and he was/is having a hard time tuning his car. You could go that route, or just use the 370cc injectors. That's what RRM uses in their stage 2 setup.

 

the 370's will be good to about 190whp. coupled with an adjustable fpr, you can get a bit higher potential. the stock fuel pressure at 14.7 psi atmospheric pressure is 47-50 psi.

with the safc, the 440's are getting to the point where you can't tune unless you can control timing. the larger the injector, the bigger the reduction in injector duty cycle, the more retarded timing gets at idle. also, larger injectors don't have as fine a spray pattern as lower volume injectors.

the ideal setup is 2 injectors per cylinder, but who can afford a custom manifold? one set for off boost, one set for boost.

also, don't forget that that your lo tune maps WILL affect your hi tune maps.

 

So 370cc RC injectors are the way to go for 8-9psi then.... Like i said, the safc appeals to me mostly because I dont particularly want to mess too much with timing, and I like it's appeal to be able to change things on the fly. Just out of curiousity. With the stage 2 RRM upgrade (which bumps up to 8-9psi) i know they ditch the fmu, use the 370cc RC injectors, longer fuel rail bolts, and a pretuned Piggy, but what else is significantly changed besides the tune and the injectors....

 

A new spring is set in the wastegate to allow more boost. Also a platic restrictor plate is removed from the MAF to allow more airflow to the turbo. That's pretty much it...

 

You don't need to change your wastegate spring if you use a boost controller. IMO, using a boost controller is preferable anyway because it should reduce boost creep (though an occasional spike is pretty much inevitable).