boatman747

I just installed 2 540,s on my 31 ft Formula. 632 lift cam and new dominators. At 4500 rpms it seemed to run out of fuel. It was jetted at 97,s all the way around. Does any one have a good electric fuel pump suggestion. I have the 110 gallon per hour Holleys on right now. Is the jetting to high ?The boat was running 75 mph on gps at 4600 rpm with 30 inch bravo 4 blades.

CIG3

You have to look at more that fuel pressure. What size is the pick-up in the tank? What size fuel lines are you running?

When you get up to the 540 CU.IN. range you need lots of fuel. 1/2" lines from tank to pump with 1/2" NPT inlet and 1/2" NPT outlet. This is a #10 aeroquip. The line to the carbs should be 3/8" or #8 aeroquip. This is probably a little big but very safe to 750 HP.

You can get a 120-130 gallon per hour mechanical pump from Summit. Make sure you have a light weight fuel pump push rod or you will get cavitation.

Edelbrock- EDL-1712
Carter - CRT-M4889
Holley - HLY-12-454-20

Use the formula of 1 pound of fuel per horse power per hour. This is for wide open throttle.

Example:
500 horse power 500lbs. (fuel) per hour.

Fuel weighs 6.8 to 7 lbs. per gallon.

7/500=71.428 gallons per hour

Vinny P

I just finished setting up a fuel system for my new 540. I feel it is very important to use a return style regulator to keep the pump from dead heading. this will increase the life of the pump tremendously.
I started from the tank with a 9/16" I.D. tube to #10 lines. I used an Aeromotive 11108 electric pump, Edelbrock mechanical pump, Aeromotive pre-pump screen, Aeromotive final filter, Aeromotive By-Pass regulator with a #8 return line, #8 lines to the carb. This might be a bit over kill for a N/A 540, but in this case too much wont hurt. It will just go back to the tank.

boatman747

What size carbs did you use on your 540 set ups ?

Vinny P

I have only 1 engine. The carb is a Nickerson built 1050 Dominator that was flowed to 1160 cfm.

mcollinstn

what's your fuel pressure at WOT (taken close to the carb)?

rbtnt

CV Products has a carter style billet mechanical pump rated at 140gph I use on my 650hp motors. Here's a link to a thread that has info on them.

http://www.offshoreonly.com/forums/s...ad.php?t=38204

ratman

RANDY AT COBRA POWER has PIERCE mech 160 gallon per hour mech fuel pumps. these are the highest output mech pump i could find, i paid 160 or 165 each. he uses them on 1000+ hp blower motors. they should do the trick for you. that is once you install larger fuel lines from the tank pickup back to the fuel pumps. good luck whit your new mills. ratman

44MTI

If you want to be coast guard compliant you need to run at least a #10 line all the way to the carbs or put fire resistant sheathing on any #8's. I would run #10 as it looks cleaner than sheathing and will eliminate any questions about line size.If all you lines are correct you should not need an electric pump a good holly or BG will be plenty.I have run N/a 750 HP and now 1050hp supercharged with only mechanical pump. This will also make the rigging much cleaner, simpler and cheaper.

boatman747

My engines are gen 6 models