hdtvned

I have an 85 Scarab 1 with a 383 stroker and a Bravo drive. The hp should be around 425. I am currently running a 21P 3 blade prop at 5200 but I can feel a lot of slip. It will do 60 any time but it seems if I catch a wake or a bit of rough water that would bounce the bow up then I can get 67+ but it seems there is still a bit of slip.
The original prop was a 19P with a larger dia. It seemed to hook up better but I can rev this one way too high.
Should I try more blades or a larger dia.

Hollowpoint

I had a 222 Stinger with a 400 small block and alpha drive. Not sure of the ratio, but the original 21P SS prop wasn't near enough. If you are looking for only top speed, I put on a 15 1/2 x 25P Hydromotive on mine. That would be good for upper 70's to low 80's (speedo, not GPS) with around 450hp on my boat, but getting on plane suffered. Not being a prop expert, I would say a larger dia (like 15 1/2 vice OEM 14 3/4) and a 23P 3 or 4 blade would give the best all around performance.

My 2 cents