Club Cobra - Fuel Pressure

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On my aluminum 427 by Gessford Machine (454)
I have a 2X4 holly setup
The numbers on the carbs are.
C3AF-9510-BK-2804
C3AF-9510-BJ-2805

They have never been right, they always seem to be rich and run better on hot days, on cold days they really run bad. Today I started the car and it seemed to be running rich and possibly fouled one plug and dumped fuel all over the intake ( a puddle!). So needless to say I pulled the carbs and boxed them up and I sent them to Pro Systems. Has any one had any experiences with them?
I also noticed that the fuel pressure is a little high at 7- 8 lbs. Is this normal?
I have a mechanical Carter fuel pump, is there some kind of fuel pressure regulator I can add to adjust the fuel pressure?

When I turn off the motor I can see fuel continue to trickle down into the intake as the fuel pressure guage slowly goes to 0. This explaines the rich condition when I try to re-start the motor after going into the store. How do I correct this problem?
Below is a photo of the motor and the fuel log.
http://www.gessford.com/quotes/images/LaGrone-3338.JPG
http://www.clubcobra.com/photopost/d...csx312_35_.jpg

You might check the recomended PSI for your carb in the manual or the holley site. I think it is around 7PSI. There are many regulators on the market that go inline, some with a guage option. I like the this one offered by Pierce http://www.piercemanifolds.com/Image.../99901.419.JPG but Holley & others make them that might fit your look better

Mike,

If the fuel continues to trickle while the pressure goes to zero, then the problem is a bad float needle valve. If the valve were OK, the pressure would stay up for a while (assuming you aren't using a return line to the tank). Since it's probably new, I would just suspect some dirt in there. With the valve constantly leaking, you're also going to run rich all the time.

I don't have the Holley spec sheet here, but 7-8 psi fuel pressure seems to be on the high side.

Liquid filled fuel pressure gauge

If you have one of these,you could be setting the pressure too high by mistake.
As the tempt of the liquid increases the reading on the gauge will drop.

If in doubt,after it is at operating tempt,put a cold rag on the gauge to cool off the liquid in the gauge.

It seems to me that you have multiple problems with you install and setup--
First, you need to get control of the float settings and some needle and seats that will contro; your fuel level--start off by lowering the pressure to 3 lbs to until you get control of the inlet fuel problem
Second- if it runs better on hot days and worse on cold days you are probly way too lean
Third--which carb do you have on the front and which one on rear? The carbs set on the manifold backwards on these engines, do you have the linkages correct?
What caused the puddle of fuel on the manifold? An external fuel leak is courting disaster, more so if it is in your garage---
If you are using a liquid filled guage-most of them have a screw hole to vent the guage to atmospere so the pressure reading is balanced and correct.

8 to 9 pounds is way too much presure for carbs- 5 -6 is marginally possible to control if the needle/seat assy aren't too large

Generally a engine with a single 4v carb and center hung floats is more driveble than the side hung floats in moderate to hard turns because the floats will close off the fuel supply in the turns one way and hang open in the opposite turns

Jerry