I was wondering where you guys think a stock fuel pump wont meet demands of a 540 in terms of rpm. I know most likely as soon as one gets into it the fuel pressure will drop but im not sure. maybe 3000 rpm?

:rolleyes: I always thought horsepower determined the need for fuel not rpm.

the faster the rpm the more fuel it needs to keep up with the intake stroke. hp is a what hapons when you have enuff fuel to feed the cylinders at that rpm

A Carter 172 mechanical pump supported 696hp from my 540 (w/single 1050 dominator) on the engine dyno and never fell below 5 lbs fuel pressure.
The engine presently sits in my '70 and will be running later this week.
I do have a Mallory 140 electric installed in the car if needed.

Im getting a carter 172 in a few days but having trouble what to do with the lines. Limited budget so I dont want to go with braided bc its 4x costlier than aluminum, and I dont know what to do about size bc the carter needs (5/8") -10 AN line in whereas stock from the tank is like 3/8". How do I hook up 5/8" to the tank? Cut off the old fitting and replace? I know the best bet is to sump the car, but would prefer not to unless I can find a sump for $20.

Originally posted by chevelleracer:
the faster the rpm the more fuel it needs to keep up with the intake stroke. hp is a what hapons when you have enuff fuel to feed the cylinders at that rpm Did you see my vid yet? Let me know what ya thought for my 1st time out

Originally posted by doggy69:
I dont know what to do about size bc the carter needs (5/8") -10 AN line in whereas stock from the tank is like 3/8". How do I hook up 5/8" to the tank? Easy!
You can buy an adapter the will reduce the -10AN fitting on the pump to -06AN male. Then install a -06 AN tube nut and 3/8" tubing sleeve on the car's steel fuel line, flaring the end of the line. Another option is to buy the type fitting that doesn't require flaring.
Then all that's needed is a short section of -06 AN braided hose, male on one end-female on the other, to connect from the car's line fitting to the pump inlet adapter.

i put an adapter fitting on my 3/8" hard line, to go to 8an stainless braided, to the carter, and 8 an to the carb from the pump.

Wont running stock(3/8"?) sized fuel line to my carter 172 restrict flow at all? The stock pump is only around 60gph.

i cant get that vid to work. :( you going to be out this weekend coming up? if so let me know ill head up your way to hang out.

your from Tom's river, probably no more then 1 hour, 15 minutes from englishtown, this coming Sunday i'll be at Englishtown (most likely without my car), however my racing friend will be there with his car, turning low 10 second passes with a 3/8" fuel line and mallory 140 pump, dead head regulator, drawing fuel from an unbaffled, un-sumped, stock fuel tank.

if you're interested in attending, it will be an enlightening day for you, if not, thats alright.

Id like to be out playing this weekend but Ill be workign bout 50 hrs bc chevelles are damn expensive

Originally posted by Motor Martyr:
your from Tom's river, probably no more then 1 hour, 15 minutes from englishtown, this coming Sunday i'll be at Englishtown (most likely without my car), however my racing friend will be there with his car, turning low 10 second passes with a 3/8" fuel line and mallory 140 pump, dead head regulator, drawing fuel from an unbaffled, un-sumped, stock fuel tank.

if you're interested in attending, it will be an enlightening day for you, if not, thats alright. Only thing that concerns me is that an electric pump which is pushing the fuel whereas mine will be pulling through 15ft of line. Does it matter?

Originally posted by chevelleracer:
i cant get that vid to work. :( you going to be out this weekend coming up? if so let me know ill head up your way to hang out. Why wont it work?

the electrics work better, and you're building a pretty big motor, but Tom (MC45471) has an equally large motor running 10.70's with a Carter 172 pulling through the line. i dont know what size line he uses, maybe he will chime in.

Hey there,

I use a -10 line from a sumped tank. Actually I would try using the stock 3/8 line first.

http://www.boomspeed.com/mc71454/fuel6.JPG

This pic is a few years old, but you can see the fittings that were used. The other end of the braided hose is pushed on to the stock 3/8 line over the nipple end and double clamped, never had a problem using this system for 2 seasons and 11.30's to 11.40's.

I went to the sumped tank because I needed a new tank anyway and I used -10 line because I got such a super deal at a swap meet for a whole bunch of -10 fittings for peanuts. The -10 line is overkill for what I do, but the cost was 1/2 than -8 because of the fittings deal.

SO, try the 3/8 line first set up with the fitting adapters.

Thanks Tom