635 h.p. out of a 502 ?
 

i'm looking at a boat that has twinn 502 motor's and the guy say's that they are 635 h.p. a peice .
is that to much h.p. for a 502 na. motor or is that over kill
he said i should get about 250 hour's before top end rebuild.
what do you guy's think :)
thank's for your help
mike

Re: 635 h.p. out of a 502 ?
 

supercharged or normally aspirated?

depending on the parts inside and the rpm it is designed to run.

635HP at 5000-5200rpm is pretty easy on most parts, 635hp at 6000 is a lot tougher on everything.

If it's a NA motor then it must have some good stuff, at least ask for proof of HP and what went into motors for starters.

Oh and wait for some more opinions :D

Re: 635 h.p. out of a 502 ?
 

carb motor
i will see the boat tommorow and ask for more info .
i just wanted to know what to ask :)
thank's
mike

Re: 635 h.p. out of a 502 ?
 

what cam
what heads
what compression

Re: 635 h.p. out of a 502 ?
 

Pistons should be forged
rods
lifters, rocker gear etc.


It's not easy to make 635 hp in a 502 without running fairly high compression and aftermarket heads with a big cam.

find out who built the motors, that will tell a lot

Re: 635 h.p. out of a 502 ?
 

thank's
if they had good part's. would they be a reliable motor package.
thank's

Re: 635 h.p. out of a 502 ?
 

You really need to see the verified build specs from the builder of the engines in that boat, insist on a sea trial, and a leak-down test, before writing any checks. --- Jer

Re: 635 h.p. out of a 502 ?
 

If they are all good parts, probably yes. Its hard to tell good parts from the outside. If the seller can answer the questions that Wobble and I said, thans its probably true. The other way to tell is on the water test. Depending on the boat and the speed it runs. If its say a 25' Outlaw, and it runs 65, than its no where near that HP. If it runs mid to upper 70's than it probably is. (gps speed, not speedo)

EDIT: I missed the twin engine part of your post. But I think you get the idea.

Re: 635 h.p. out of a 502 ?
 

thank's i am going on seatrail tommorow
33 powerplay . he say it will do low 90 mph ""92-94""
thank's

Re: 635 h.p. out of a 502 ?
 

If it runs that speed, than it is probably pretty close to those power levels. Very well built heavy boat.