80, but personally thats to much power for that boat.

chine walk
 

Any boat without a pad wil walk.....way cant u just drop the tabs a bit

Thats what I was saying in my post. You can fool with the tabs a little, but it scrubs some speed .... but you can make up for that with more horsepower. If you get the tabs down a little to far, you further unload the rear of the boat, shift the cg of the boat farther forward, and it can start to bow steer. If you get the cg too far forward, you will end up with the rear of the boat coming around the front of the boat and everyone will be swimming. Is your boat a stepped hull or straight hull. The straight hulls handle the horsepower better, from my experiences.

27 fountain has a pad.

chine
 

Its a stepped hull....i will index my k planes and drive...i will not drop the taabsbelow nuetral......also how bout a one inch shortie lu

not really
 

Look at a allison...bullet....hydrostream....boat needs a flat surface to get up on

95 would have probably had a low X dim (~17" or there-abouts), so you probably could benefit some with a shorter drive.

My 97 27 stepped hull stock 502MPI with CMI exhaust runs 70 all day long on a 23 pitch prop at 5000rpm at 650' elevation and 102 degrees out. Adding 240HP will gain at least 10-12 mph!! Unless the non step version is that much slower, I would certainly think he will be high 70's to low 80's. There are several whippled 502's in 27's that are pushing mid to high 80's

x dim
 

Does anyone with a newr 27 have a xdim measurment and im assuming it has to be a lefty lower

I was told by Fountain that my '97 has an X of 17.25". I have recently installed a -3 lower and the bottom of the boat is now even with the top of the gear case