Thanks for helping

The thermoquad carb on my car was dripping gas around the bowl vent, plus i know the top gasket was weak from taking it apart a few times, so i took it off for a rebuild

i'm also replacing the performer 440 manifold with an indy 2d. car has rpm heads, 231/237 @0.050, ~0.560 lift, tti headers, 2.5" exh, 2.76 rear and a 727 automatic

so my question is about the fuel pump. the car would i think starve for fuel in long 1st or 2nd gear pulls, around 4000rpm. it has 276's so it takes a while... i have a wideband and the tq is pretty spot on till it starts missing and goes lean, so i figure it is emptying the bowls??

i put a new stock fuel pump on for $40 and not much difference

I was thinking a carter M4862 http://www.summitracing.com/parts/crt-m4862/overview/make/chrysler

or something like that. i'd like to run a -6 AN line to the carb, i have a fitting on it, and i dunno if i need a regulator for a pump like that? i surely want a mechanical pump

also should i think about up-sizing the line to the tank. it's probably 5/16"

cheers and thanks Moparts

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was thinking a carter M4862 http://www.summitracing.com/parts/crt-m4862/overview/make/chrysler

or something like that. i'd like to run a -6 AN line to the carb, i have a fitting on it, and i dunno if i need a regulator for a pump like that? i surely want a mechanical pump

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I tried this exact pump on my 499 stroker. It died after a few months. I disassembled it and found that one of the valves was not sealing allowing gas to flow in both directions through it. Maybe I just got unlucky but an expensive experience being left on the side of the road when that sucker died.

I went back to the Holley pump and so far, so good. You shouldn't need a regulator on the Holley or Carter pumps. My Holley puts out 7 psi at idle.

I am running a 493 also,,and at the drag strip the hi volume Carter pump couldnt supply enough fuel to the carb and leaned out ,,at the 1000 ft mark after shifting at 5600 thru 1.st and 2 nd..as it got close to the 1320 it bogged ,,flat ran out of fuel to the carb...so I then installed an electric boost fuel pump...no more problems.. never had fuel starvation on the road..only use the electric pump at the track..

A mech fuel pump feeds the Dominator on my 499" MOST of the time. I have an electric for supplement when needed.

The pump depends on the entire fuel system to do it's job. Check your fuel pump push rod. Even a little wear can cause a lack of delivery at maximum demand. And any restrictions in the entire fuel system can cause a delivery issue.

One quick test I did when trying to figure out my fuel system was to run a hose from the tank directly to the pump to see if that alone addresses the issue. That area is where I spent the most time and got the biggest increase in flow.

Good luck!

What I would suggest is (1) T at the carb inlet & run a neoprene hose out to a round vac gauge taped on the windshield (most have a psi scale) & see if you have 3 or possibly 4 psi at the load/rpm when it starts missing. (2) measure the pushrod (iirc need 3.250") (3) plumb a 2 gallon can of gas in the eng compartment to the pump inlet & repeat the run. (4) make sure the filter between pump/carb ain't restricted (need a hi flo type). Our stock car with 5/16 line/OE airtex mech pump (class rules) did not starve at 6200 RPM at the end of the straights at WOT (tho it was a 360/2bbl & would be less thirsty than yours). Not sure if the TQ could easily be opened up to 3/8" fittings/dual feed & not being a TQ guy if that is even needed but I'd be inclined to think not but you do have alot of cubes & it's WOT/high RPM. Easy stuff first (gauge/pushrod). EDIT "the carb shop" in Eldon Missouri (Google it) may have larger needle/seat assys (IF) needed. He mfrs alot of parts in house/tech sharp/personable guy to work with. MORE EDIT You might confirm that the psi part of the vac gauge is accurate by comparing it to a known quality fuel psi gauge as fuel psi gauges in general are notoriously inaccurate

I use just an electric pump to feed my 493. One reason is I can run the fuel line in the upper part of the pass wheelwell and keep it away from the eng and eng heat as much as I can until it goes to the carb. I am using the Holley black pump and it has worked fine for me feeding my 850 Holley DP. I use a 3/8 line and it runs in the 10's with no fuel problem. Good luck , Ron