Jamie77905

Ok guys I know I am probably opening a can of worms, but here is my question. I have a 1990 32 excel with twin 454 motors( a lil motor work) and bravo 1 drives. I have 25 pitch 3 blade mirage props on it, they have not had any work done to them just stock. I am full throttle a at 74mph. Do you think a different prop set up would get me more top end? If so what would you recommend trying?

donzi matt

iTrader: (1)

What is it turning for RPM?

Jamie77905

4800

fastdonzi

If your max rpm is 4800 with 3 blade props you may want to try some Mirage+ 23's or some Bravo1 22's

Jamie77905

Ok please help me out,as I am prop stupid lol. What would the23 or 22 accomplish? Also I hear a lot of people going with a 4 blade is there any advantage to that?

donzi matt

iTrader: (1)

What 454's are they? Mag or 330's? A 4 blade will help holeshot, usually at the expense of a couple of MPH.

Edit: Is this GPS speed or from the dreamometer?

Jamie77905

The speed is off of GPS. As far as motors go, and I know this sounds dumb, but the guy I bought the boat from bought it out of repo from the bank, so I have no idea about whats done to the motors. They run great I can tell they have a beefier cam and they have roller rockers, stainless marine exhaust as far as internals I have never pulled the top end apart to look. I added Quick fuel 750's to them at the beginning of the year and it really woke them up

donzi matt

iTrader: (1)

Without knowing what the motors are, and where they make power, it is hard to tell if propping down and bringing the RPM's up will make more power. If they are cast crank 2 bolt motors with peanut port heads (330) version, leave them where they are. If they are rectangle port mag motors, they will benefit from spinning a bit higher. Not knowing what cam is in them adds another question to the setup.

Jamie77905

Yeah I figured 74 was respectable out of a lead sled lol, but I really do not want to tear into the motors just to find out cause they run way too good to do that the way they are now! I might try to find a set of used props just to see if it makes a difference or not.

donzi matt

iTrader: (1)

I don't blame you.

I would probably limit the RPM to 5000 not knowing what the bottom ends are. It would suck to spit a rod spinning it to 5400 and finding out it has 3/8 bolt rods instead of 7/16 bolt rods that way.