cjsdad62

Well,
I took the boat out yesterday and got about 50-52 mph, assuming 10-12 slip, but could only get 3500 RPM. It felt like the bow came up more than last time, the whole boat too, alot higher out of the water. That was with a 17 x 17 bronze prop. I thought I would be able to turn alot more rpm going down 5 on the pitch from 15-1/4 x 22. I probably lost some with the 2" larger OD. I think I need more than just a carburated big block for this size boat with only one drive.

The engine is:
9:1 Comp, .060 over on the bore,
small isky roller cam, .570" lift, 240 dur. @ .050, 110 centers
edlebrock performer rpm heads,
Victor Jr. Intake, and an 850 holley.
How many HP would you think? Enough for a 28' boat?
I haven't even gotten the weight or COG yet.

Anyone have any thoughts???
It was very nice getting up on plane at least. If I can just get it to 4800 or 5000 rpm, I would be happy.
Thanks for any help.

mmwalters

If you only turned 3500rpm that is not even close to the power band of that cam. Tell us more abour that drive. Did you build it? Any pictures? Seems to me you have plenty of HP.Just need to dail in the prop

cjsdad62

Here's a picture of it. I did build it. Got any ideas on what prop to try?

johnnyboatman

iTrader: (5)

looks like it needs more of a cleaver style prop.

mmwalters

That inboard prop Just will not work, Cleaver or chopper style prop will work much better