fuel pressure question on EFI

[NJB71]

So i have been driving my Bronco around w/ swapped EFI for last 4 months, really enjoy it. I was wondering, after a conversation with a skiff racer(flat hulled river boat, incorporates v8's jacked) he asked me what my FP was, I said I have a kirban adjustable and I set it to 48psi. He was blown away, he wanted to know why i had it set so high. I always thought 39psi was standard, and I had set a little higher, cause I run 24lbs injectors, big heads, e303 cam, yadayada......am I off mark? now the FP conversation started cause my idle still dances a little, he thinks I'm dumping to much fuel in there?

 

[broncnaz]

I'd drop it down to the stock 39 psi more than likely it will fix your idle issues. There's rarely a need to up the PSI with bigger injectors as your adding more fuel by virture of the bigger injector.
I've even heard of some guys running lower than stock FP and it fixed the idle issue completely with no other issues. At most you'll get a code that indicates the AF mixture is to lean and you may need to up the FP from there.

 

[NJB71]

I will try and Ty broncnaz

 

[DirtDonk]

Is stock 39 psi at idle and low load conditions (with high vacuum signal), and 45 at lower vacuum (more load) on a stock setup with vacuum modulated regulator?
Or does it just maintain the same 39 all the way through the load range?

Reason I ask is that with a stock regulator, the V6 runs 35 at high-vac, 40 at low-vac, and thought the V8 acted pretty much the same way.

Thanks

Paul

 

[hartbronco]

Is stock 39 psi at idle and low load conditions (with high vacuum signal), and 45 at lower vacuum (more load) on a stock setup with vacuum modulated regulator?
Or does it just maintain the same 39 all the way through the load range?

Reason I ask is that with a stock regulator, the V6 runs 35 at high-vac, 40 at low-vac, and thought the V8 acted pretty much the same way.

Thanks

Paul

It should change through the range , The fuel PR has 90psi on the pump side and 38-40psi on the fuel rail side , and when you mash the skinny pedle it should change up and down as fuel is needed .