Fuel pump question

DSYenko · #1 07-22-2005, 06:25 AM

Is there any difference in factory GM fuel pump outputs or pressures.I have built a street performance 454 with 400-450 horse and used a 74 454 block and a 750 Holley and was wondering what fuel pump to use.I am trying to keep it stock looking but was'nt sure if a LS6 or Vette tri power pump had more output than the average GM pump? Also thought maybe they were to big to use without a return line since the heavy hitters in the later 60's had a return line .I am putting the engine in a 76 Malibu and it has NO return line.Any knowledge on this would be appreciated,Thanks Duane

Chevy454 · #2 07-22-2005, 06:37 AM

The Holley carb'd cars didn't have return lines...the Quadrajet cars got those. We run the standard big block AC pump on our Camaro, and we're putting out around 430+ HP at the rear wheels...last summer I swapped in a hi-flo Carter mechanical pump, and noticed no change...

DSYenko · #3 07-22-2005, 06:51 AM

NUF SAID on pumps,but why did the quadrajets only get the return line,and did they use the same pump as the Holleys that didnt get the extra line?

DSYenko · #4 07-22-2005, 07:38 AM

Any idea what that part number is for the AC pump you use?Id appreciate it,Thanks

**k92** · #5 07-22-2005, 10:09 PM

My low mile all original ls6's fuel pump has the return line.I believe early ls6's did not have the return line.My car is a june car.

**COPO** · #6 07-22-2005, 10:17 PM

I saw a July LS-6 car that had a return line as well. I just assumed it was an LS-5 car. Is this change documented?

bad1racing · #7 07-22-2005, 10:50 PM

DSYenko,The part number could be 1 of 2.73-75 Chevelle 454 4" from bottom to mtg holes #6472381.73 Chevelle 454 4.5" from bottom to mtg holes #7470761.These are OE applications so anything is possible.Hope this helps.
Kendall

Chevy454 · #8 07-23-2005, 12:46 AM

DS: ours is the stock 396/427 AC replacement, available from our sponsor above (D&R Classic Automotive)...not near as fancy as what a lot of the guys are running, but it carries our fat @ssed Camaro through the traps at 113+...

DSYenko · #9 07-23-2005, 04:17 AM

Rob Thanks I will contact them and tell them i want what you have unless you have the number right off hand?
Thanks again

Chevy454 · #10 07-23-2005, 05:51 AM

I believe this would be it, but when you call, make sure this is for the solid lifter big blocks (read: Holley cars):

http://www.drclassic.com/catalog/Cam...el/S00021.html

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