Upgrade To 4 Blade Prop?

[sleek]

i currently have a powerquest laser 27 footer with a 454 mag. i run a mirage plus 21p prop and was considering changing to a 4 blade bravo 1 or revolution4. any info or suggestions? the mirage plus that i was running has some light damage to the cup area of the prop and i want to atleast get the one i have fixed so i thought i might save the money and go for a new one. any advantages of drawbacks to switching?

[mike37]

I'm not a prop expert
but you will see a better hole shot with a 4blade
and a little loss in top speed
it is passable for you to see a better top speed
with the 4blade if your slip ratio on the 3blade is hi

[TIMINATOR]

Typically if the "X" dimension is high, the boat will go faster, if it's lower, it will probably slow it down. Take a pic of it from the rear with the drive in the neutral position and measure it too and post it here. The more info that you post, the better answers you will get. TIMINATOR

[Tahiti350]

X dimension is how deep the drive sits in retation to the botom of the hull? If so, how can I move it, and how much would be suggested. Can't get pic's or measure as I am out of country, boat is in Pacific NW. Will be home in mid-Jan. Running a 20' Tahiti with SBC/OMC 800 (trimmable) that uses the rubber boot in the transom so should have some leeway. Can I just shim the motor and drive mounts up (thinking about building a rail mount like the V-drives use)? What kind of gaines are possible with 1" less "X", as the boot should give me that much without streching it? Always looking for a little more SPEED, and better handling.
GaryB> Tahiti 350

[Essex502]

I found that my hull responded better to the 3 blade Mirage Plus 25P than the 4 blade Bravo 1 24P. With the 3 plade prop the hull is rock solid. With the 4 blade the boat was squirrelly and didn't want hardly any trim. Out of the hole the Bravo 1 was a rocket while I couldn't get the boat to settle well enough to see what it did to the top end. With the Mirage Plus, I am a little more sluggish than the Bravo one on the bottom end but all the way to WOT it'l sit like it is on rails at any trim angle.
Each hull is different and reacts differently to the shape and size of the prop you select. Some props provide more bow lift while others have more stern lift. Only experimentation will tell you which type of prop works best for your boat. You should look for a retailer that will let you try the prop you are interested in before you buy it or let you trade it in after purchase for a different one if it doesn't work. Teague Marine used to do this but I think they now have a restocking fee. Check with them to see what their policy is. Otherwise, see if you can find a friend that will let you try the prop before dropping $400+ bucks on a new one.

[Havasu Hangin']

With the 4 blade the boat was squirrelly and didn't want hardly any trim.
A 4 blade will have more stern lift. On some boats, too much stern lift will make it tough to carry the nose.

[STVBOY]

A 4 blade will have more stern lift. On some boats, too much stern lift will make it tough to carry the nose.
AHH thats not really totally true. Depending on what the prop is designed to do the fourth blade just adds that much more of bow lift or stern lift. I would say if you have to give it alot of positive trim than I would consider a 4blade or if it blows out in turns the 4th will keep it hooked up.

[Wild Horses]

Also the smallest you can get a bravo 1 is a 22 pitch, and the largest you can get a rev 4 in is a 23 pitch.
I don't know if you could run a 22 bravo it would probably be to much prop and kill your top end.
I run a 23 rev 4 at 5700 rpm and it runs a lot like my 25 mirage plus on the top with a better hole shot and no blow out on turns. :clover:
Clint