Big Boys Toys

Looking for some suggestions on which way to go regarding propellers.
Application 1989 Formula 292 SR1 Bravo1 Drives, 502 CU IN Crate Motors 450 HP each Currently running 72 MPH at 5400 rpm.I'm currently running 14 3/4 " X 23 Pitch three blades rubber hub. I did spin the hub out one propeller, had it fixed and I'm back running. Do I go three blade 25 P or four blade 24? Solid hub or rubber hub!
Thanks
Brian

throttleup

You'll need solid hubs for your engine application. The rubber hubs just won't hold up. If you have the old style props a solid hub can be welded in.

It depends on what you are looking for from your props. In your application a 3 blade would most likely give you a better top end. A 4 blade would give you a better cruise speed but might cost you 2 mph on the top end. The 4 blade props handle better and are better in rought water than 3 blade props.

If you boat in smooth water most of the time the 3 blades may be the way to go.

Depending on which 3 blade props you have now will determine what pitch prop to go with if you are considering new props. YHou may be able to go with Mirage Plus 23's if you currently have Mirage 23's now.

Matt

BajaRunner

Matt

Ive always wondered this, how do 4 blades make your boat handle better in the rough?

HOUSTONPROP

BIG Boy Toys The ACCLERATOR PROP WORKS GREAT ON YOUR BOAT.

Jason ,if you need call me and I will glady explain your question.

throttleup

Multiple blade props have a huge advantage over 3 blade props as fas as handling and acceration. There isn't a single spec boat in the offshore race circuit that runs 3 blade props. Some run 4 blade but most run 5 and 6 blade props.

One reason is the ability of the mulitple blade props to handle rough water. When a boat is properly set up for rough water the boat is running almost flat and the props are near the surface of the water. When the boat hits bumps the props come closer to the surface. With multiple blades the props stay "hooked up" which allows the throttleman to stay in the throttles thus increasing the speed of the boat.

The same is true when turning. As the boat leans into a turn one prop comes closer to the surface. With multiple blade this allows more throttle to be applied to the prop near the surface than with a 3 or 4 blade prop.

3 blade props work well on older boats that require bow lift with non stepped hulls. Newer boats with multiple steps typically perform better with more blades and don't need the bow lift.

Of course there are exceptions to every rule. It still comes down to testing as many different props as possible to find the one that performs the best for as individuals style.

Matt

Live Wire II

I have a newer 292 with 6.2s, 1.65 gears. I'm running a bone stock set of 28p bravo 1, 4 blades. Seems to be the best so far, just wondreing if something else would work better all around, great cruise, good WOT.

Grog

A 5 blade Hydro P5 really woke up my 1999 271 Fastech. One of my complaints about the 4 blade Merc prop was about how long it took to get the heavy Formula stern out of the water, especially with a full load. Now I use about 1/4 throttle and it really hooks up well. With the P5, I can stay on plane at 25 mph now which impossible before. Midrange acceleration is great. No complaints on the top end either. I am sure I can do 1-2 mph better top end with a different prop but the overall performance in the speed range where most of my running is spent is so good that I am willing to make that small sacrifice. Slip #'s are in the 10-12% range at WOT.

Talk to Julie at Throttle Up. She'll set you up.

Live Wire II

Just in case any one is interested, I have a set of Merc Racing labbed 30p, 4 blade for sale. Give me a call, we'll talk about price.

gferdon

Live Wire...

I have an '04 Fountain with the exact engine, drive and props as your 292...let me know where to call, I may be interested in your 30" Bravo 1's (yes?) but they may be too much prop, let's talk.

GF