I'm getting 5000 rpm with the Michigan Wheel Apollo 21 that I have. That puts me at the lower end of available pitch for the Bravo 1 props. I am wanting to decide between a 21" Mirage Plus and a 22" Bravo 1.
I'm happy with the planing and ride with my current prop, I'd make the change to get more cruise efficiency and top end.
I imagine the 3 spoke Mirage will do better speed and the Bravo a little better low speed plane. Am I right?
If the Bravo will be within a mile per hour of the Mirage I'd go that way to get the lower speed planing and reduced slip.
I don't have a speed reading and won't be able to get one unless I borrow a prop. I bottomed my Apollo last Sunday so I'll be limping on an old aluminum propeller this weekend.

Alpha 1 gen II, 1.5 ratio, 10:1 forged piston, cast crank, roller 383 with Quickfuel 750M carb; small port, small valve Dart Iron Eagle heads and Thunderbolt V ignition. Never dyno'd so I don't know HP. I kinda hope it's approaching 400 HP and 460 TQ. But if it's a dud I may be getting less.

I would steer away from the 22" Bravo. The 21" MIrage will likely not be significantly different than the Apollo you have now. You need more RPM to get more MPH. The only way to do that is go down in pitch. You will likely enjoy the results. A 19" Mirage or perhaps Laser II would be on the faster end of props. I've found the best props for out of the hole work to be a High 5 and the Rev 4. Personally I've become a fan of the Rev 4 for my particular application. Puts the power down like no other prop, very responsive in trim due to the longer barrel and large blades. It also has the least slip of any prop I've used (with the Mach Sterndriver being nearly equal, BTW if you can find a Mach Sterndriver in 18 or 20" pitch get it).

Try a 19" Mirage or Laser II, and a Rev 4 in 17 or 19" pitch (18" would likely be ideal but is a custom prop for the Rev 4 line). Keep in mind the Rev 4 will load the motor like a 3 blade with about 2"+ more pitch. You need to get your motor in the 5400-5700 rpm range.

Go with a 21 Mirage Plus over the Bravo. The Alpha may not survive with that much bite and a Bravo prop will just barely fit because of the larger diameter.

The 19 pitch props appeal, but I believe the Thunderbolt V will rev limit me at 5150 RPM. Maybe my next move is to ditch that ignition for one that allows more engine revs.

You motor likely peaks at 5400-5700 rpm which is why I suggested the lower pitch props. At least get to your existing rev limit and go from there. I was able to raise mine when tuning but I'm EFI.

I grabbed a pristine 19 pitch Mirage Plus from a lakeside homeowner yesterday. But I had left my prop wrench in the truck so I didn't get to run it. I have an oil leak to attend on my next boat day, probably Sunday, then I'll report back.

The reason I was thinking the Bravo 1 was that they run 2" under. So a 22 acts like it's 20 pitch. Winnipesaukee is usually choppy with a wind down the length often causing rollers and whitecaps. So the 4 blade appeals for low speed planing with tucked drive and lots of tab in the chop.

I'll probably get a Mirage plus 21 if the 19 revs too high. It won't work the drive as hard and it's more likely to get me top end.

That long barrel on the Rev 4 looks like it would assist quite a bit in managing trim.

Damn, I don't want to be that guy with rows of props on the shelf in the boat shed!

LOL. That's me. Unfortunately for you (I'm on same lake) they are all mostly 3 blade Cleavers.

I've never run a Bravo 1 4 blade, but most of the comments I've seen are they run 1" under, not 2". I guess I need to add to my prop shed and get a Bravo 1 database started..

Bravo 1 props are generally .5-1" lighter than stamped pitch. The extra blade also reduces rpm. A 23 Mirage Plus and 22 Bravo spin about the same rpm.

Could be wrong but I doth think Thunderbolt V has a Rev Limiter. Anyway the 4 blade will eventually break your alpha. So if your are looking to save gas by increasing efficiency at the expense of of you drive... Then it wont be efficient. It will be expensive. I think the Mirage will be the fastest and the easiest to tune "Lab"

Chris