I have a HSR and my FPR went out. Instead of waiting on a mail order on from Holley or an aftermarket one I just piced up a Buick one from the local autoparts store.
My question is I though that it would have a static fuel pressure of 43.5. Wrong, it is at 39psi... Should I let that bother me to bad?
My injectors are already too big IMO 36#.
I have a 355 with vortec heads. My cam only has .475 lift and a 108 lobe separation.
Thanks for any advice

 

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With or without the vac line connected ?

 

With it disconnected, it drops to 30 psi connected.

 

I used this calculator,
http://www.witchhunter.com/injectorcalc1.php
With a static pressure of 39 psi the injectors drop to 34 lb injectors. I don't believe that hurts me with my setup. Just looking for some reassurance that I am ok assuming that. B/c you know what they say when you assume...

 

With no vacuum you really want 43#. Lower than that and the fuel doesn't atomize as well. GM figured this out with the LS engines as they run much higher fuel pressure. AFPR aren't expensive and a good one will last many many years.

 

Thanks Tibo,
That was what I am worried about. We are only talking about 4.3 PSI but if that is enough to make the injectors not atomize correctly then I need to get a different regulator. I might go give Autozone hell and tell them to give me another FPR. Does anyone know if a Buick Grand National was suppose to have 43.5 PSI?
I should have just waited and ordered a Kirban...

 

Just ask them to return it as defective because it doesn't put out a proper pressure. If the guy says no ask for a manager and if he says no ask for the district manager, all while being polite. Buy an aftermarket.