[WDCreech]

Originally Posted by garysredrod

I am running a good mechanical pump with a non socked 3/8 line pushing through a Summit wafer style filter and a large .149 dia. seat which I did notice a difference when I went to that size and was also told by SD that I should be fine into the 11's if everything was as I told them with about this combo. I have not ruled out a pusher pump, I have just not pursued it yet.
As far as the cam goes it is basically a Comp XE284 with 1.5 Harland Sharp rockers

The problem is not your cam! As David Jones said, your fuel pump can't keep up with the engine at full throttle. When I drove my 461 cu in '63 LeMans on the street, I had the same problem. I put two diaphram type electric pumps, back at the tank, with a switch to turn them on when needed. It completely solved the problem. The mechanical pump has no trouble pulling through a diaphram pump, but would through a vane, if it were shut off, so you don't need to run the diaphram pump, for normal driving.

[Gary D]

Do you have a recommended pump for this application that does not break the bank?
I notced you said 2 pumps! Were you running the mechanical up front with the 2 you mentioned in the rear? Total of 3 pumps for racing and only needed 1 for street driving.

[WDCreech]

Originally Posted by garysredrod

Do you have a recommended pump for this application that does not break the bank?
I notced you said 2 pumps! Were you running the mechanical up front with the 2 you mentioned in the rear? Total of 3 pumps for racing and only needed 1 for street driving.

I assume that this post was addressed to me. Yes, I ran the mechanical pump on the engine, with two pumps at the tank. I ran this combo on two different engines. First was a .030" over 389 with dual quads, the second was a stroked 428 with a 1000 cfm Thermoquad. I think the electric pumps were Stewart Warner, but not sure. It's been over forty years.

[Gary D]

Originally Posted by WDCreech

I assume that this post was addressed to me. Yes, I ran the mechanical pump on the engine, with two pumps at the tank. I ran this combo on two different engines. First was a .030" over 389 with dual quads, the second was a stroked 428 with a 1000 cfm Thermoquad. I think the electric pumps were Stewart Warner, but not sure. It's been over forty years.

Yes this was directed to you Bill. I am new at this format of trouble shooting and this forum. I was on Summits site and they do not show a electric diaphram pump. I like the idea of not having to run it unless I need it. Thanks again for your help and Davids also.