625 Road Demon

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Sep 1, 2007 | 01:20 AM

johnboy427

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From: The Vieux Ford, Kansas

625 Road Demon

I jut put an old Holley Streed Dominator intake and a 625cfm road demon on my 79 F-250 with a 400, the cam is a Crane Engergizer with .524lift and 272 duration. Now my bellows black/blue smoke and i can't seem to get the float level set on the secondaries, I just keep screwing them down and still can't even get it to register in the window. I have had many holleys and they seem to be pretty much the same as the demon. Could the float really be about ten complete turns high? I didn't even thing they had that much adjustment in them. I can get it to idle fairly well at about 850 RPMs other than the smoke. Any help would be much appreciated.
-Johnboy

Oh yeah I took it around the block and it runs great (smoke seems to lessen as RPMS increase) and it didn't smoke at all with the two barrell i didn't pull the distributor but i did take the cap off.

Last edited by johnboy427; Sep 1, 2007 at 01:23 AM. Reason: more info

Sep 1, 2007 | 05:26 PM

LxMan1

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From: Louisville,Ky.

Sounds like a piece of debris in the rear needle and seat. Pull it out, clean it then reinstall and set yout floats. They should be just below the window.

Sep 2, 2007 | 12:34 AM

johnboy427

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From: The Vieux Ford, Kansas

Thanks I tried that this evening and even tried an old Holley I had with the same result I am starting to suspect intake gasket leak on sucking a little oil and causing a low vaccume condition and mabey opening the power vavle causing the rich condition. I have ordred new gaskets and its looking like wednesday before i can mess with it, I also think i will be buying a Weiand #8010 intake, I knew that single plane street dominator wouldn't have the best low end but was worse than i excpected.
-johnboy

Sep 2, 2007 | 04:43 AM

LxMan1

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From: Louisville,Ky.

Good luck, I hope that fixes it.

Sep 2, 2007 | 11:25 AM

fastback69

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From: Heart of Dixie

What is your fuel pressure? I had to put a FP regulator in front of my holley to prevent the pump from blowing the needle and seat open and overfilling the bowls. I had to lower the pressure to 6 1/2 psi but it works much better.

Sep 7, 2007 | 08:01 PM

johnboy427

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From: The Vieux Ford, Kansas

Well I got the truck running good now, intake was sucking oil at cyls 2,3,5,and6. I put a fuel pressure gauge in the port on the dual inlet line and it reads about 6psi untill it warms up then it reads just above zero. What might cause this? Is the pump bad, or is it most likely a bad line behind the pump sucking air? I had custom exhast put on that goes no where near the fuel lines or gas tank so i don't think its boiling gas in the line. Will this cause a lean condition and ruin my motor?