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kenhaw
04-05-2009, 06:05 AM
Ok guys, help is needed.

I have a 69 camaro with a chevy 385 Fastburn engine with the hot cam kit.
A couple of months ago I had my engine stall on me and just before that I noticed my fuelpressure was droping sometimes. I have a holley mechanical fuelpump and stainless steel lines. I have since upgraded everything with a RobbMc sending unit in the tank, 8 AN lines all the way to the RobbMc pressure regulator getting feed from a Carter mechanical fuelpump, 2 new RobbMc filters, 100 and 40 micron. All lines are new 8 and 6 AN. My pump should be able to provide 7 - 8.5 psi but I am not seing that much. I have a pressure gauge inside the car and also in the engine compartment. I am seing maybe 6 psi and sometimes 4. What is going on. I have had the car for 3 or 4 years and never had this problem before. Before the pressure would be around 8 all the time. Is this a cam lobe problem? Have read that it is important to use the right fuel pump pushrod and called a dealer who told me to use the standard non bronze tipped type. My engine has about 20.000 miles on it. When I changed the fuelpump I noticed that the pump pushrod was the normal one so I just installed that again. I have no return fuellnes since RobbMc told me that it isnt needed. I live in the south of france and it gets hot here but have never had this problem before so I dont think vapour lock is the problem either. If I change my pump to an electric which one should I get? My car is blown and carburated and if possible I would prefer not to run a return line.

Please help.

Thx

Kenneth

Vegas69
04-05-2009, 08:38 AM
Check your fuel filters for debris first. Then I would look at the pump and cam lobe second. There should be a spec from a cam manufacturer on how much travel the rod travels.

kenhaw
04-05-2009, 12:09 PM
It is a completely new installation. It is impossible that there is any debris in the fuelfilters. The fuelfilters are also RobbMc and are pretty big. The tank is as new inside and was completely empty before the upgrade. The pump is a new Carter pump.
I have a bad feeling that it could be the camshaft. How difficult it is to change a camshaft? I am not worried about all the disassembly prior to getting to the camshaft but the camshaft itself could be a problem or?

Kenneth

kenhaw
04-12-2009, 11:18 AM
Cant I just install one of my pressure gauges before the pressure regulator to check pressure further down the line? I am absolutely sure it isnt fuel line or filters or tank unit, so I the pressure is as low before the pressure regulator then it is the cam lobe.