I cant seem to get my fuel pressure below 50psi with my bbk adjustable regulator. I know that this is a bit too rich for my 350 TPI but i have the adjustment screw backed out all the way to where its not even touching the plate and its still at 50psi. Anyone else ever experience this?

 

Maybe an bad gauge ? or incorrect installed diagraphm..
Maybe you need to loosen it again and dubbelcheck that its correctly installed.

Running 50PSI or more isnt good for the fuelpump over time..

 

Well I took the reg off and reinstalled it just to make sure it was assembled correctly and I didnt find any problems. What else would make the fuel pressure spike like that?

 

Check for restrictions on the return fuel lines.

 

I cant think of anything that would restrict the lines but in any event what could I do about it? Run some fuel system cleaner maybe? I just changed the fuel filter, thats not an issue....

 

A kink in the line maybe. I'm not sure if it was clogged that you'd be able to clean it. I'm also not sure how common this is. But I had a similar problem and that was suggested to me. Mine, however, turned out to be a diaphragm problem.

 

I too have a BBK but I haven't had a problem with mine. I have my screw all the way out and I have stock pressure. I only adjust it at the track before a nitrous run... These are good suggestions... I would try maybe the vacuum line that connects to it... If that doesn't work, I would put the stock back on and see if its still doing it...good luck

 

Can you higher the pressure then ? or is it always 50PSI ?

 

I think you can go higher...

 

when i installed my bbk i could not get lower then 45 psi lol...cant help u.

but hey did u have to trim the screw that the kit came with? in the kit i got it was like a 1/4inch to long and would hit the plenum. i trimmed it a bit so i could adjust it.

 

oh yeah, I remember I trimmed mine too...and btw do you mean 50psi all rpm's or idle? because 50psi sounds good for WOT but idle...38psi-42psi...

 

The pressure should be constant, WOT or idle, the electric fuel pump won't pump any harder unless its either adjusted for the higher pressure (AFPR) or the return line is bent or partially clogged. Only other thing it could be, is a higher pressure pump that I can think of.... If it were me, I would take off the fuel cap and blow pressure back in the return line and listen for it at the tank.

 

My TPI has never been like that... even when I had a stock pressure regulator...when I first installed my fuel pressure gauge, (interior) It would range at different points weather it was idle to WOT...

 

Fuelpressure shall change with the throttle, because the FPR is connectoed to a vacuum..

Thats also why you have to unplug the vacuum hose when setting the pressure..
Because the pressure is higher without vacuum..)

When idling the engine is not pulling much and you get maybe 38PSI of pressure, when giving throttle the engine starts to suck more air and the fuelpressure shall increase to give that extra fuel, and at WOT it shall be ~44PSI if you got 38 at idle...

So ResurrectingZ, an TPI engine shall have changing fuelpressure