Hi Dick,
As I recall from my long-ago road-racing days, my SBC 'vette used about
20 gph and put out a guestimated 350 or so hp with a 7000rpm working
redline. And that 20 gph includes turns and braking when little fuel is
used, and certainly was not at full revs even when at full throttle,
except just before shifts, etc. Hence, I gotta think that 700+hp at
full throttle and full revs continuously is gonna require on the order
of 60-100 gph. The 3/8" tubes used on stock street high perf engines
only flow about half what a 1/2" tube will.
Conclusion: Go with the -8 fuel line and a bigger pump.
Alternatively, how about two -6 lines with two pumps in parallel (with a
low-pressure checkvalve in each line downstream of the pumps to prevent
backflow if one fails--that is, if the pumps themselves don't have a
checkvalve built in)?
At the least, I'd put a pressure gauge at the carb so you can monitor
pressure there. If you've got the pressure there (I assume 6-8psi or
so), then the flow should be adequate. (I'm not familiar with the large
Holleys, but would assume that the needle/seat assemblies also flow
substantially more than, say, a "little" 650cfm unit.)
Benn
"opinion worth what you paid for it"
----- Original Message -----
From: "Dick J" <lsr_man@yahoo.com>
To: "land speed" <land-speed@autox.team.net>
Sent: Thursday, July 28, 2005 7:43 AM
Subject: Fuel Flow Question
> I spoke with a Holley Tech Rep for a while this morning, and he said
that my 454, at sustained 7000 RPM, would require 919 CFM and he
recommended a 1000 CFM carb.Now my question is, how much gas will it
need. I know some of you guys are running real exotic fuel pumps, but I
already have a Holley blue pump and regulator which flows about 70gph to
the motor at 14psi which should be enough pump.
>
> My question is: Will the stock 3/8" fuel line flow well enough to
feed this motor?
>
> Dick J
> In East Texas
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