how much HP with the stock fuel/sea water pump support? has anyone tried the new KEPP fuel pump upgrade? I have a fresh pair of 540's that I don't want to starve for fuel

Me too ........ same question, 'cept I have a single BB, close to the same CI.

Anyone ???

A Holley or Carter high volume pump diaphram assembly will screw right on to the Merc armature housing. Works great!
Dave

Merc. used the stock fuel/water pump on their SC-600hp. The KEPP fuel pump upgrade is good for 700hp. This Billit pump is rated for 850hp.

Dave, Have you tried/used a Holly or Carter diaphram on the Merc housing ? If so, which one did you use and how did it work out for you ? I have a 557 that should max out in the 5700-5800 RPM range. I'd like to stay with the mechanical pump if possible.

Thanks - Bill

Bill,

What's the PSI on the pump you mention ?

Bill,
The Holley 12-454-11, 12-454-13 and 12-454-20 will all bolt up as will the Carters with the six screw flange (the Merc armature housing is a Carter unit)
Yes, I have used the -11 for a supply pump for the high pressure pump on supercharged EFI setups up to 1000hp. The -13 and -20 will require a regulator.
Dave

Thanks Dave !!

It's 8 psi and 1200 lbs. per hour.

I think I'm going to try the KEPP pump, they are self regulated right? who's got the best price on a pair??