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BowlingSS
January 12th, 2008, 02:10 PM
Fuel Pressure with a Walbro pump?
I just installed a fuel pressure gage on my fuel rail so I could check the PSI. I do have a Walbro pump. My PSI was only 52. Is that low for a LS1? It was a cheap gage. I am planing on going to #42 injectors after my head install and wanted to know my fuel pressure. I though it should have been aroung 58 PSI. This PSI was at idle.:cheers:


Bill
:cheers: :cheers:

5.7ute
January 12th, 2008, 02:14 PM
If it was a failing pump the pressure would drop further when the fuel demand went up. I would say your guage is either incorrect or your regulator is on the way out.

BowlingSS
January 12th, 2008, 02:17 PM
If it was a failing pump the pressure would drop further when the fuel demand went up. I would say your guage is either incorrect or your regulator is on the way out.
It could be the cheap gage I bought. The gage I bought is:
http://www.visionmotorworks.com/gmls1lt1enfu.html

Thanks,
Bill
:cheers:

mr.prick
January 12th, 2008, 04:20 PM
i had a mechanical gauge that failed,
and had the line in the tank come unhooked.
both of these things cause me some grief.
if you are experiencing fuel starvation you will know it.
there is always the autometer FP sending unit mod
if you want to monitor fuel pressure.
BTW i average 64psi with my walbro 255.

eboggs_jkvl
January 13th, 2008, 02:11 AM
Well, it looks like a Camaro in your avatar so I'll guess and continue.

58 is the normal idle and running pressure. You will drop down to lower than that (53-55) at WOT but you should adjust your PE tables to cover the lower pressure. Running my setup, I have a rising rate pressure regulator and something like a boost-a-pump for the aeromotive 1000 that I'm running. Normally I run 52 PSI cruising and normal driving. When i get to 0 vacuum, my B-a-P kicks in and my pressure jumps to 58. As my boost increases the fuel pressure goes up 1 PSI per every 1 PSI of boost. Thus, at full boost 12 PSI, my fuel pressure is 70 PSI.

Elmer