don't know where to start?
 

Im doing a project boat and I have never run the boat before so I don't have a clue where to start with a prop.
The boat is a 1990 Profile gt 26 it has a small pad and I am running a 475/500 hp big block with a bravo 1 with a 136 drive it has a Bobs nose cone with a low water pick up on it. Any help would be great.
Thanks Keith

24-26P Bravo1 ???

Yes its a bravo 1 and its A drive from another boat that I had in the garage.
I never ran the boat and never had one with a pad. would you run a four or a three blade
Thanks Keith

Keith. Powerplay J was talking about the Mercury Bravo1 prop.

It depends on where the power is made. Even if the motor spins "only" 5200 max, a 26" (25") B1 would put it at 80 mph with a 12% slip. I think that number is too high with that power. I would prop for about 73-75 and go from there. Overall, when stuff is new, baseline testing is needed. Either 23" Rev4 or Bravo1 24" if spinning 5200 and up. The Rev4 has an overall better lift than the B1, so that would be my first choice.

thanks I dont know the weight of the boat but it seems very light looking at the lay up and in way its built even kinda cheap I hate to say. I have a new transom in it would you consider raising the drive? now would be the time to do it. I hopeing it will be a fun good all around boat its pretty much a 24 x 7 with a foot and a half added only a 6 foot wide transom.

i agree with A.O. Razor use a smaller prop . i have a 24baja with a 136drive . i use a 24bravo one prop.truning it at 5800 and i have 718hp 540dart motor . prop your boat to the redline on your motor if it is 5200 then make shore you put the prop that make it spin that good luck :drink:

Yup what A.O. Razor said. I know there are a lot of variables but I would start with a 24 B1 4 blade. It might spin a bigger prop but I think its a good place to start.

I do not disagree with you one bit but I believe this hull likes the lift from the B1 props.

I would probably start with 24 Bravo 4 blade. It should run about a 70-75mph if the slip is correct.
Being an older boat, the drive might be set pretty deep and it may actually like a Mirage Plus.
The 24 Bravo should get you decent baseline though.

thank you very much guys Ill give that a try