Fuel Pump Pressure - Dyno issue
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Joined: Jan 2002
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From: Marietta ga
Fuel Pump Pressure - Dyno issue
What is the GPH rating of a stock fuel pump???
I was on the dyno yesterday and having trouble keeping my top end from leaning out, especial above 5k RPMs. The car stayed at 13:1 untill 4500 RPM, then climed to 14:1 slightly over 5k RPMs. The car made 305 rwhp at 4950 and 340 rwtq at 4250. I will post the dyno graph later
I changed my fuel pump to a holley 80 GPH mechanical pump. This seemed to help, but my secondary fuel bowl still went a little low, but not below the sight window. I am running a Demon 650 mech sec, 110 needle and seat, 76 primary, 82 secondary, 6.5 power valve, and fuel at the top mark in the sight window.
355
230/236 cam - comp xe274h
Air Gap RPM
10.5:1
Ported and port matched to headers/intake -186's
36* total timing
I was on the dyno yesterday and having trouble keeping my top end from leaning out, especial above 5k RPMs. The car stayed at 13:1 untill 4500 RPM, then climed to 14:1 slightly over 5k RPMs. The car made 305 rwhp at 4950 and 340 rwtq at 4250. I will post the dyno graph later
I changed my fuel pump to a holley 80 GPH mechanical pump. This seemed to help, but my secondary fuel bowl still went a little low, but not below the sight window. I am running a Demon 650 mech sec, 110 needle and seat, 76 primary, 82 secondary, 6.5 power valve, and fuel at the top mark in the sight window.
355
230/236 cam - comp xe274h
Air Gap RPM
10.5:1
Ported and port matched to headers/intake -186's
36* total timing
Last edited by Cory1970; May 10, 2006 at 05:51 PM.
Thread Starter
Pro
Joined: Jan 2002
Posts: 624
Likes: 0
From: Marietta ga
Originally Posted by big_G
I was thinking the peak hp should be more likely at 6000rpm with that cam.
I am guessing it is because of the loss of fuel pressure. Does anyone know how much fuel the stock fuel pump flows???
