Prop?
 

Im almost done with my build. 462ci, Bob m cam, 781 heads, with forged domed pistons 13.8cc.. 750 holly, sm exhaust, .027 head gasket, around 9.25 compression, +/- 500 HP Where do you guys think i will be with a prop? Its a 1989 24 Pantera. Had a 21 with prob 360 hp before.
i was thinking at least 23, do they make a 24?
thanks

What drive are you running?

If you go from 360hp to about 500hp then its about and 800rpm gain if you kept the same prop. Being 500hp, you probably want to spin the engine at a higher rpm than you were.

If you switch to a 23" prop, you will still be reving about 400rpms higher than you were. It all depends on what you target rpm is compared to what it was with the old engine.

Use BBlades test program.

i was running a similar set up and ran a 25 four blade

25 4 blads seems big, what rpm and speed were you getting??

I havent talked with bob m yet about what max rpm he recommends. my old motor was only turning 4800 wop w/21 3 blade and needed a valve job, 2-3 cylinders low compression.

Bravo 1 drive

If the drive height was set by Pantera at 17" you will probably like the 3 blade props best for top end, Mirage or Mirage plus in 23. The Mirage plus will spin more like a 24 pitch, about 200 rpm's less than a standard Mirage.

Agree with Ironman above, my hull didnt like the 4 blades(except the Trophy plus), Did you call again yesterday Adam, sorry if ya did, I had another missed call from a 954 #, I turn my phone off when in meetings, so just leave a message. I have a standard mirage 23 that you can try, and also have that 4 blade in a similar pitch, like I said, it has been reworked, and not stamped, so knows the real pitch?? The only thing I have in a Mirage plus is my 21.

Rick

Mine likes the 3-blade Mirage. A 23" will probably be the ticket depending on the recommended rpm range. I've got slightly more HP than you will have and turn my 23" between 5600-5800, solid 75 mph...

Jeff... isn't yours a Mirage+? At least it used to be.

I was thinking it should be a plus also, but a standard mirage 23 will get him close.

I don't think it is...it doesn't have the "plus" on it. Unless it's an early version of one. Pressed in hub too rather than the interchangeable. (don't know if all plus's have them or not though)

Either way, it runs good with whatever version it is... :drink:

If you get a chance to try a 25 Merc. Tempest plus 3 blade (bass boat prop) by all means give it a try.. Its a high rake prop & will lift the boat well,,

Not sure what you are looking for but if its top end then the 3 blades seen to work best on the 24's & as mentioned the mirages & mirage+'s work well, but if you can get ahold of a tempest or tempest plus give it a shot.. My old 79 24' had a low X due to the TRS and was no doubt a several hundred pounds heavier than your boat with about 450-475hp with 454 cu" & a 25 pitch Tempest plus worked best on it from what I tried.. I would have really liked to tried a 23 in the same prop but never got a chance to.. the boat ran right at 70 on GPS and was a blast to drive a speed due to the lift & high trim it took to run it all out..

I appreciate all the help guys i will let you know what happens, still waiting on parts for 2 weeks now.!!!

I have run a 3 blade Mirage and a 4 blade. If I recall, the three blade runs better. I am going to have the same basic set up as you, with a new engine going in this spring. 89, 24, with a stroker 496 at about 525 hp. I was running about 70-72 with about 450 hp around 4800 RPMs. This was with the three blade.

What rpm range should i be running?

Somewhere around 4800-5200 I would think, did ya ever get your motor done? I'll be out of town this weekend, but if ya wanna run the following I am up for it.

I finally got cam 1 month later, the motor should be ready to drop in by tuesday, wednesday.

I would bet closer to 5400-5500 rpms or so. Check with Bob M to see he what he thinks.

Just trying to keep him safe, at least until broken in:drink:

Give me a day or so heads up when your gonna get it wet, and I'll run out with ya.