sidmanic

Is there a max fuel pressure for 60lb injectors? Is 75psi too much?

hammeron

if you mean with the car running, i wouldn't think
75psi would be too much. i routinely go over 70 psi
WOT and i have 39lb injectors


if you mean with the car not running, i am not sure

sidmanic

Running. I know that all fuel injectors have a minimum pressure (something like 43 psi), I was wondering if it could work against you having too much pressure? Sometimes more is bad.

mygt500

Well, I have 60 # injectors and more is definitely not bad IMHO. I did have a problem with running a bit rich and my tune had to be changed to fix that. I know Saleen 0607(something like that) had a stumble problem on start up just as I did and it was the O2 sensors that could not get the A/F right until the car warmed up a bit (about 10 min). I read in a different post that his was fixed by doing something with the tune so it won't switch to closed loop/open loop system after warm up for 10 minutes as opposed to 30 seconds. (dont quote me) and it fixed his problem. I actually picked up about 10 more RWHP on the dyno but it was 30 degrees cooler and the humidity was less which makes a difference in HP/TQ. So a tune is everything and I was told the spray pattern is better than the smaller injectors as well. I love this forum and the info it provides!!!!!! Hope it helps J

sidmanic

My concern is only if it is too much. There is a fuel pressure regulator installed (return style system) so turning it down is not an issue.

The O2 sensor is something that I will mention to the tuner to see if it might be an issue with the idle problem that keeps coming up. (high idle)

Saleen05797

Someone correct me if I'm wrong but the idle can be changed with a tune, correct?

And Mygt500, did doing that to your O2 sensors fix your problem too?

sidmanic

Yep.

Dex

high idle on start up?

sidmanic

Yeah, I think we got that figured out. Not giving the O2 sensors enough time to warm up. Gonna have the tuner fix that.
Car would idle sometimes at 1500-2000rpm on startup then go back to normal idle after 1-3 min.

Fullsayl

Have you replaced the TB on your ride? The reason I ask is that improperly set TB voltage will cause the same thing.