I have the 96T/A OBD1 .030 LT1 with forged pistons, ported heads ...etc. What should the fuel pressure be set to? I currently have it set at 40PSI at idle with the vac line off. It has a 255lph intank pump and 30lb injectors BBk58mmTB. any ideas?? thanks any help would be appreciated~~~rob

 

Is 40 PSI ok, or set it lower with the big pump?

 

Whatd did your engine builder/tuner recommend? Mine told me 47 pounds on the stroker. Somebody more technical may ghave a better answer but my understanding is the spray pattern and pressure need to be matched for optimum efficiency.

 

You didn't mention what cam you are using. You also didn't mention if you have custom tuning. With 30lb injectors I would definitely use custom tuning. These are two extremely critical points but also go ahead and tell us what CAI, MAF, Valve size (stock?), headers, and rockers you are using. All of these things affect flow. If you are having someone like pcm4less tune it, then they are usually really good at recommending what pressure to go w/. PCM originally told me 47 w/ my setup. 45 ended up being the sweet spot.

 

Ok, here ya go:

.030 over96LT1 block
forged 10.4:1 pistons with a .039 head gasket
Moly rings
Reconditioned rods with ARP bolts
polished crank, all new bearings(duh)
CC306 cam, AFR Hydra-Rev kit
Comp R lifters, ARP head bolts ,ARP rocker Arm studs
Crane gold 1.6rr's
Ported stock heads with stock valves, Ported intake, about a stage 2 port job
BBK58mmTB, Ford SVO30lb injectors, Aeromotive AFPR
RK Sport 1-3/4 headers,!cats, OBD1 conversion,
Hooker aerochamber 3inch exhaust with cutout
I have the Ram air hood for the T/A so no CAI
Descreened MAF ,Custom tuning by cz28.com's very own MADWOLF
Hmm im sure im forgetting things

 

Rob, I just thought I'd mention that your injectors are programmed as 31.6 lb/hr. This is their flow rating at 43.5 PSI, so that's what I'd say you should set it to.

 

I was told by my mechanic that you will get a better spray pattern part-throttle if it's 39-40 psi as this the pressure the injectors were designed to run under. That would put WOT at about 43psi. This should be the pressure unless you are trying to compensate for injectors that are too small.

Putting a Racetronix kit in has raised my fuel to 46 which has had a noticable effect on my idle (rougher) even though it's holding 14.7:1. That jives with the "better atomization" theory.

-Alex