Thread: pros an cons of 4bar fp over 3bar

i would like your guys imput without ass hattery, thank you

4 bar isn't good for some injectors. Also, some fuel pumps cannot support over 80psi which 4 bar boosted setups hit a lot of times.

You get more fuel flow with 4 bar, and better fuel atomization.

yeah just make sure you have a good fuel pump, 4 bar has been proven to be better as long as your using the right injectors and a good fuel pump such as a walbro 255, the stock fuel pump is only good for soo much.

Would 370's be able to hold up to 4bar?

on my old turbo car i ran 4bar with 370s and a walbro 255

And another bit about 4 bar fuel pressure. Injectors can lock open if too high fuel pressure is seen. If boosting to high levels (2+ bar) the fuel pressure will be at 6 bar (instead of 5 bar). It's easy to see how you'd lock open the injectors easier with higher base fuel pressure. This obviously isn't something to be too concerned about as not many run that much boost, but it's something to know. You don't want to build 35 psi at 5k and all of a sudden have a deluge of fuel.

I ran a stock fuel pump and 259cc injectors for 100k miles at 4.13bar. I only changed the fuel pump becuase I thought it was cutting out but it turned out to be a maf problem. I say the stock pump is just fine at 4bar. At least the 99g20t pump is.

so 370s +255 walbro will work?

Work for what?

Yep, did you ever get a walbro 255 yet?