sierraspringsjay

Hi everyone, I just found this forum while searching for some opinions on a prop. I have a 2001 30' SSB Heritage, step hull, whipple supercharged 502 (720hp on dyno) 1.5 ratio with bravo one 27p. At WOT I'm @ 5100rpm and GPS @ 63mph. Looking to go to a 28p, could I expect to see some improvement. Thanks to all who respond, much appreciated. By the way, we only run her in the lakes around here.

bbladesprops

Was the 27 B1 prop made from a 26 or 28?

Sounds like your rpm's might be a little low. If this is true, going up in pitch could hurt over all performance and aid only in cruise speeds.

sierraspringsjay

Sorry Brett, my bad I just realized I had put down 27 not 26. I thought the rpms were low to. I'm only running about 5 pounds of boost, but should be seeing a faster top end than what I'm getting. I was running about 25 gallons and 3 adults for those #'s. Prop slip maybe?
http://s108.photobucket.com/albums/n...ent=Boat-1.jpg

Griff

I think you need more rpm, not less. The 28" will lower the rpms 300-400 and you'll be lugging the engine and creating a greater risk of detonation. What rpm did it make 720hp at???? At 5100, you might only be making 620hp. Your speeds seem way slow for 720hp. How much does the boat weigh???? Your slip #'s are pretty high even for a heavy boat. I would think with a stepped bottom you should be at 12-14% prop slip even in a heavy boat and you are over 20%.

sierraspringsjay

Thanks Griff, I thought the slip was high. Just had the prop examined, and found out its completely out of wack. The tech thinks the previous owner might have tried to repair the 26 at sometime cuz it has been shaved down. He also thinks the rev limiter has been set way to low, so its back to the water for some new test and bump up the boost a little. Thanks to all for the responces. Great site!!!!!!!!