Dtile

I was just wondering, after seeing a few fuel pumps on ebay...Is there any differnece in performance with a electric fuel pump than a manual pump installed on a late model GM with supercharger (250 B&M). Currently mine is manuel. And what gph is recommended if I decided to go the electric route? Thanks for any input.
mike

cooltoys61

Better get an Aeromotive 1100 and wire it to cut out if you lose oil pressure. It will support 800-900HP and set up with the return(re-circulating) regulator by Aeromotive also (forgot the #) call Aeromotive, they are very helpful with the tech line.

Vinny P

I just rigged up a complete Aeromotive system. I used their 11108 pump, 13207 Return Regulator, 12307 pre-pump filter, 12306 filter after the pump. I also used an Edelbrock mechanical pump with a check valve coupled to a 'T' fitting. All lines are #10, including a tank pick-up that I made myself.

Crazyhorse

The stock Merc pump on the seawater pump will support 700-800 horsepower.

Dtile

But my motorr only turns about 550 hp, single carbs on the 454. Would electric increase hp?
Would a crossover kit increase hp too?

US1 Fountain

iTrader: (1)

Carb will only flow so much fuel. Doesn't care how the fuel gets there as long as enough of it does. You don't gain HP by more volume with a bigger pump, you lose HP with a too small of a pump. Which leads to no HP immediately after. I ran the stock pump on my HP465 (502) motor with B&M 250 and 1050 Dominator with no problem. A fuel gauge at the carb will let you know if your pump is pushing enough fuel or not.
A crossover won't make any noticable difference in HP on the water. Just in the numbers on a dyno. There are pros and cons on crossovers. Best to do a search on them here.
Not sure about your setup, currently a stock 454 with the plan of repowering with a 250 with dual carbs and adding a crossover?

Dtile

US1,
Currently my setup is unknown, I just bought the boat and the last owner wasnt too clear. He claimed the motors were done by Innovation Marine, one 30 over, the other 60 over...I see some posts with people getting over 600 hp on stock 250 blowers, and was wondering why since my motors are likley higher end guts, Innovation marine has a reputation of installing higher end stuff, how to get there without going crazy with breaking down the motors. New cmi headers, a 250 blower (thought not sure since I see some pics of 250's with two carbs...I was just wondering how to get another 50 hp out of the two.
The boat TOP is 84 @ 5400, claims to be 7-8 psi boost, 35 fountain, 89'. 160 hull hours, 40 hours on the motors. speedmaster 2's trs's...(whats the Top hp on those btw)?
last owner claimed 540-550 hp each. Thanks for the replys!
mike

Crazyhorse

I'd guess that you're making more than 550 with seven to eight pounds boost unless the motors were 330's before. My 509 engines with B&M 250 superchargers and single 1050 carbs, mild hydraulic flat-tappet cams make 696 at 7 pounds.

KNOT-RIGHT

In your posts you refer to"The boat TOP is 84 @ 5400, claims to be 7-8 psi boost"
Have you ran the boat yet?
I see fuel pressure gauges on engines is there boost gauges on dash?
If your suspecting fuel. A presure drop at WOT may be noticicable.

600 hp is starting to push the limits of the TRS drive. possible upgrades
are the Konrads. Also if your running stock 72-c borg warners they have limitations
also.

Stock mercury Fuel pump is good to 700 horse power as Crazyhorse said. I beleave its close to 110gph.

My last boat I purchased the owner claimed it did 106 Mph . No trial run. (Port motor in a
box) Finaly built it and droped in the water. 91 mph was all it had. laying down at 5000rpm.
Tank pickups were to small. No way did it run 106. So I installed 1/2 inch pickups with a Claysmith mechanical all #10 lines with return style regulator back to the tank. this will easily suport 1000 hp and its simple.
Remember its harder for the pump to feed one single carb then it is to feed two carbs.

Gerry

Dtile

Jerry, yeah no gauges yet, I just purchased a few to install on to dash...I did take it out for an hour before I winterized it and the gps was at 84 WOT. Planing was bad. And all the joints at the exhust were leaking a bit. The oil pressure on both engines were good, at 50-75 all day. I guess its all I can get out of those drives, I wonder if Innovations keeps records of the motors they built, cant find them on the web anywhere though, but I have heard of them doing good work over the years. Though I never owned a performance boat like this., so its all new to me.. what would you do to squeeze another 50 hp each, if at all.. thanks for the input.