Herminator

I did a search and could'nt find anything on this. Can someone help me out. I my old setup was 310 cc injectors with 10:1 disk in my FMU. My setup is B16, greddy turbo, 225lph high flow in tank fuel pump, I just installed 440 cc injectors and was wondering should I keep the 10:1 or something leaner like 8:1?

turbosol

More like a 4:1, I used a 6:1 with 370s. What Are you using to idle your injectors? Have you considered the AFC hack or SMC. Then you could ditch the fmu all together. I'm pretty satisfied with my set-up on the AFC hack, I run plenty rich at 10 psi.

spooled b16

10:1 that's stupid rich that's what i run with the stock fuel pump and stock injectors.

4:1

spooled b16

Whats the rest of your fuel set up and how satisfied are you? Looks like we live in the same nieghborhood slightly. Just wondering cause i was thinking about going with a walbro 255lph with 370cc injectors and a V-afc on my b16a2. I want to run 10psi daily driven, but i wonder if the engine will live on stock internals. It seems fine now, but im only running the tial .35 bar spring (4.5psi) and when i mean daily driven, i mean i drive this to college and work everday

your thoughts

93H22ACX

i dont understand the FMU disks....so the lower it is the leaner it is? is the 10:1 on the FMU lean? If so, how does it correlate to the A/F ratio? Wouldnt 10:1 A/F be too rich?


Thanks

turbosol

The fmu ratio is "fuel pressure:boost pressure." So with a 10:1 fmu for every 1 psi of boost your fuel pressure would increase 10 psi. At 5 psi of boost your fuel pressure would raise an additional 50 psi over your baseline fuel pressure, usually 40ish. Resulting in 90 psi, plus you should also take into account that your stock FPR is a 1:1 so there's another 5 psi of fuel pressure, 95 psi. Running more than 100 psi of fuel pressure isn't the best thing for your injectors, though at one time on another motor I have ran in excess of 125 psi of fuel pressure with no issues. But, I certainly don't recommend it.