carb jetting and pressure?
#1
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I have holley 700's on my small blocks. The engines are chevy 355's pumping about 400 hp. Edlebroch performer rpm intakes with 1" spacers. What jets should I have in the primary and secondaries?
I also have holley mechanical 110 fuel pumps with a regulator. I noticed my fuel pressure would idle at 6psi but at higher rpm's would cut down to three. I took off the regulators and am running the 8an fuel line straight to the fuel rail. Is this normal or am I endangering my engines?
I also have holley mechanical 110 fuel pumps with a regulator. I noticed my fuel pressure would idle at 6psi but at higher rpm's would cut down to three. I took off the regulators and am running the 8an fuel line straight to the fuel rail. Is this normal or am I endangering my engines?
Last edited by wstultz; 09-07-2006 at 12:19 PM.
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Originally Posted by wstultz
I have holley 700's on my small blocks. The engines are chevy 355's pumping about 400 hp. Edlebroch performer rpm intakes with 1" spacers. What jets should I have in the primary and secondaries?
I also have holley mechanical 110 fuel pumps with a regulator. I noticed my fuel pressure would idle at 6psi but at higher rpm's would cut down to three. I took off the regulators and am running the 8an fuel line straight to the fuel rail. Is this normal or am I endangering my engines?
I also have holley mechanical 110 fuel pumps with a regulator. I noticed my fuel pressure would idle at 6psi but at higher rpm's would cut down to three. I took off the regulators and am running the 8an fuel line straight to the fuel rail. Is this normal or am I endangering my engines?
#3
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Thanks wobble....that answers one question. I looked up the pumps and they have a shut off at 6.5psi to 8 psi.
As for the other question......no answer.
Come on, I need some engine guys to chime in or I will be forced to another weekend of cussing and breaking things.
As for the other question......no answer.
Come on, I need some engine guys to chime in or I will be forced to another weekend of cussing and breaking things.
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Right now I have 70 in the front and 74 in the rear. Had 72 in front and 82 in rear and she was bogging down at 4000.
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If your psi is between 6-8psi with regulator off and it stays in between this range up thru WOT you do not need the regulator. If you are 8psi or over, get that regulator back on. If your psi still goes under 5psi without regulator, you have a fuel supply issue.
As far as jetting - can't help you there. Sorry. But the plugs + performance will tell you everything you want to know about jetting while a vacuum guage will help tell you idle micture setting and power valve choice.
As far as jetting - can't help you there. Sorry. But the plugs + performance will tell you everything you want to know about jetting while a vacuum guage will help tell you idle micture setting and power valve choice.