To be honest I don't believe that you need a 140 gph pump. I just installed Mallory 140's but on the dyno I ran an internally regulated Mallory 110 and it supported 600HP easily.

(Mallory 110 Marine Electric Fuel Pump)
This Mallory Marine electric fuel pump delivers 110 gallons per hour with a 7 PSI output. Built for reliability, the construction of this pump features a billet aluminum housing with 3/8" NPT ports, a highly efficient gerotor design for quiet operations with a stable fuel output, and corrosion resistant coatings to withstand abusive marine environments

is the mallory 110 gonna cut it? i like the idea of it being sdjustable also though so the 140 may be better? i am looking into aeromotive now also, the 11211 and 11212 pumps. i am not sure what to do. i keep finding deals on automoyive pumps but not marine. i know everyone says not to use automotive ........

That's what I did, and I used the standard merc fuel pump for a 500hp. I started with gen VI 502 415hp long block. Realy easy to install and setup - two bolts and your done. I'm also running thunderbolt ignition and 850 holley.

i cant go mechanical due to my sea pump. a new sea pump will cost more then a electric fuel pump