Blue Meanie wrote:
I got a question. I just installed a 390 Holley carb on a spreadbore manifold and i was wondering about the E.G.R. The E.G.R. valve interferes with the carb body so it had to go. I didn't go with a block off plate but i did get rid of the diaphram housing and gutted the valve. This way i have a soild base to anchor back to the manifold. I was able to seal the valve port but im not too sure about the 2 smaller holes that are on the underside of the base. I didn't think that they passed thru to the intake side but i question this because i cant get the motor to idle down below 800 RPM. If anyone has any input on this i would gladly like to hear it Thanks...
I think that autozone or pep boyz sells a block off plate. it wouldn't hurt to call and ask.
the holes in the EGR are for the diaphram to actuate. you might want to spray some carb cleaner on the EGR housing to see if you have a vacuume leak.
on some holleys you can adjust the idle using the secondary throttle plates. you might want to look and make sure yours doesn't have an adjustment. I had a 390 on my 3.8, but can't remember if it had that adjustment.
I would also say to check the idle screw, idle mixture and the float bowl fuel level.
hope this helps