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I'll throw a large case on one of my boats and run with Craig for no points in 750 as long as I can get both boats out there and there is props for both of us. If not, Craig is welcome to my 25 pitch prop. It's about 12" diameter or a little smaller. Never measured it. If there is time in between the classes I can just bring one boat and swap out lower units at the race. It would only take about 10 min to switch them out. If we find out what kind of handicap if any might be needed to run a large case with the 750 boats, racers being able to quickly swap out lower units between races might be an easy way to get a bigger boat count in 750 and allow racers to run 2 classes with their boat. Just looking at the lower unit, I think it might be able to run the same height and get water to it if only the bottom holes were left open and and the case was contoured a bit to help the water get there.

Also, since the big case has the same ratio as the 2 cylinder gears, would that not mean the same prop would be used on the 2 cylinder as it would the 3 cylinder if they were running close to the same or does the big case cause more slip requiring a higher pitch?

A T850 56er with a big case is not even close to a fair race with a 2 banger, you'll be running in the 60's all day while the two banger will be back in the 53-54 ish numbers. A 70hp 49er with a big case is a better comparable.

You need the higher pitch cause you got the power to turn it while the 2 banger doesn't.

Kevi, the guys running the big case on their 49 VooDoo's run 22 to 24 pitch same as the T750 nitro races. The difference is they have more diameter. We may find the small diameter props do not work with the larger case.
My guess is the large case will be poor into the corner, but fast out of the corner. The pure T750's will catch them on the straights. Driver will and does make a difference.

[quote="LittleChargerA T850 56er with a big case is not even close to a fair race with a 2 banger, you'll be running in the 60's all day while the two banger will be back in the 53-54 ish numbers. A 70hp 49er with a big case is a better comparable.[/quote]

Don ran his 56 big case VooDoo at Gravenhurst last year. We didn't get a good read on the boat because of the trim being stuck in the out position. LC is correct. The 56 is not a close to fair match with the 2 cylinder or 43 cubic inch 3 cylinder T750s. The 49 longs will be a good match. DOC ran a long, big foot Yamaha. I think it was a handful to drive especially with rack style steering. The intent is to get family, cottage boats with their 49s on. Not race hulls. Jake's Checkmate is a type we want to see. A cottage boat you can race time to tome.

That's what made me wonder why Craig would need a 25 pitch to use for testing? I figured if the motor was working at about the same speeds he would be running the same pitch prop. So really what he should be looking for is a 23 but bigger diameter then if it's going to be running competitive with the 2 bangers. I guess that 23 x 12 3/4 Hdog mentioned he had would be a better one for him? Anyway, my 25 is available if needed

Anyone going to Gravenhurst from my area that can tow a boat? I might throw my 2 banger on critch and run it in 750 if I can get it there.

fun fact - on our checkmate with the longshaft big gear case. Normally I run a 23p 12 3/4 chopper with a massive through prop exhaust, @ 6400 rpm maybe? I just tried a 27p 12 cleaver, and it slips like crazy. My tac was hitting 7000 no problem, and It went 5mph slower than the big chopper.

Sounds like the prop to run at GH Jake