Here's the way the car's set up as it sits

350, warmed over vortec heads, xe274cam, 10.68 compression, Forged trw's, Xrods, 4130 eagle forged crank, balanced, 1 3/4" headers, 780holley vac sec dual feed.

Feeding that is a 6psi, 110 gph Carter street pump, that has so far held 6spi constantly. Feeding that is 3/8 line back to the picup, a single 3/8 line to the fue "rail" it's a splitter for the bowls basically.

As it sits, i'm fairly certain the fuel system is adequate, only having to support tops about 420 hp.

However down th road ways i'm planning on running a dual stage shot of nitrous something on the lines of a 75/150 shot, launchin on the 75 with the 150 on delay.

What type of up grades are necessary, when i take the rear out to put the 12 bolt in, i'm going to upgrade the fuel system. I do have that sinking feeling i'm going be running an8 lines from a bigger pickup all the way to a bigger pump.

Any suggestions for line Size, and a good mechanical pump that would support the present 400hp+ and a small-moderate size shot of the juice safely and effectively.

Thanks

 

I always recommend on carbed applications, that a second line added to the fuel tank and dedicated pump be installed for the nitrous system. some exceptions might be; a 305 carbed car with a shot like yours or smaller. when considering a pump, a tiny blue holly electric pump can barely supply an engine but works great as a dedicated nitrous fuel pump. a carter electric can also do it but not the engine and nitrous both.

 

What about a mechanical pump. I'd assume it would have to be quite large, in order to supply them both. IE something with a 1/2 inlet and a half inch outlet to supply the volume.

I do like the two pump idea, with the secondary pump being electric...

As for primary pumps, I Tend to shy away from them, Not a big fan of intake pumps.

The only reason i'd run an electric pump for the primary means of fuel delivery is if i ran a fuel cell in it.

 

you wrote "intake pump" but I will assume you meant "in-tank" and thats not what Im suggesting. I mean add another line so that your mechanical (carb) and "in-line" electric (nitrous) pumps are not competing for drawn fuel from the tank. I know of no mechanical pumps that can make that kind of support (some close but not quite) by themselves. I know that $ome belt driven mechanical race car fuel pump$ can do it definitely.

 

yeah you got me on the "intake" pump... my typing hasn't improved over the years...

so your basically suggesting two stand alone fuel systems. two pickups.

I can see how that would be beneficial.

I'm not exactly sure if a mechanical pump will be able to take launching, like that anyway, i've heard of them haveing "fuel stack" problems when you get in the 1.5-6 60er range.

I'm starting with the research now. the second(nitrous system pump) ... you think a rail mounted pump would be sufficent?

 

A mechanical pump is not enough for both. a holley blue pump is enough for a 250 hp kit (.070 jet), with its own feed line. fuel stall is not a major issue with a carb because the bowls will act as reservoirs until the car is a second or two downtrack. that's part of the reason pro-stocks were able to get by with blue pumps and still run high 7s in the quarter up until the early 80s. a nitrous kit has no reservoir so if you get fuel stall, you get a full lean condition. run the mech pump for the motor, feed the blue pump with a 1/2" line and you should be fine.