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Numbr, length,Width,RPM


Well-known member
OK I have herd spin up re' diameter and max prop RPM /and same thrust less rpm with more pitch. Like i'm wondering what I have to keep an eye open for to finish this boat. But would be really good is if everyone could get a good idea what diameters and rpm /pitch can do for you. Really engine and boat reactions to the different DRIVE Options (direction) as well as RATIO'S and length from crank to prop and really didnt need to be LAST, Counter rotating! :lol:
Cold to start with there are so many variables that there is no one answer. So what hp are you running, is it DD or gear box, or belt drive, what ratio is it. What prop are you expecting to run, how big a prop can you run, what rpm are you wanting to run your engine at, and the list goes on so give us a specific and we will try our best to completely muddy ythe waters to whare you end up just puttin it on and tryin anyways. BUT we will be doing it with the best of intentions. Oh yeah how much money you want to spend also is important. let us know
I'll have a 2.68 box sitting on my doorstep soon. Was thinking 3 blade sensenich wide but I seem to recall waterthunder saying nobody runs a prop that long on a ride boat. I just thought it would be interesting to see what everyone else was running. HP? 489 bbc, 10/1 should get 500 anyways?
Lot's of people run big props and you will generate more thrust with the long blade however it's just like country said it depends on what you want your combo. Your boat will perform better in several areas if you give up a little of that thrust and not run the 80" or 82'' or larger props. Nothing is the best it's all about building a matched combination that performs best in the areas you prefer.
Cold Eh

I am running a 78 three blade Sensenich Ultrawide Q series set up on my boat now and I have a 520 hp WaterThunder LS6 and if I could have I would have run a 76 in like Thunder runs you can make up for the length by adding more pitch the nice thing about the shorter blades is that they Don't torque roll like the longer blades do.
You are a very fast learner Sniper them longer blades will develop more thrust but as you have learned first hand they will torque roll your boat. That's great you got your three blade please post your performance spec's when done. Snipers boat with a two blade 80" will dip the side under water if you tried. This is a case where peak thrust numbers don't mean peak performance. Because I could run a prop that will make less thrust and run circles around the 80"
It is the torque roll I was worried about with the 80/82" props. Sensenich has narrow, wide AND SUPERWIDE? I just looked at the Classic site for price guess and they don't really diferentiate. Thanks!
If you want just tell me the size of the hull, what est HP level and motor size, what gearbox ratio and the weight of your boat as in light heavy, heavy with poly or heavy with rod lockers, three seat's walk around.
OK here goes! 16' hull although it's 2' wide at the front and 8'3" wide at the back. 22" sides at the transom. The bottom works out to be about 105 square feet of flat area. Glass hull with poly. I would say medium to heavy. 489 BBC, 2.68 rotator. 500 hp should be acheivable, 10/1 cr. rod lockers. side by side rear driver with 3 in front. Thanks!
A 1/4 '' stroker 454 with a 2.68 will swing a big prop I would run a 78'' Sensenich super wide Q series 3 blade.
yepper 3 blade 78" superwide and call airboatcaptn2 on here to get one. he is giving the best deals anywhere.
Yeah, from all the post's I have learn't from in the last year I have to say I agree with your recomendation. I'll call Faron later because it's the last thing I have to buy, but i will try to comunicate with him. This thing should ROCK!!!
Cold, you've come a long way since you first started posting on here .....
If I remember right the first project was going to be with a 4 cyl. Toyota. Now you're into a big block with a gearbox, and a superwide Sensenich prop. Wow.

You've come a long, long way, sir. I'm happy for ya though, and we're all lookin forward to that boat.
You're right. That combo will kick butt 8)

I guarantee you saved thousands of dollars and years of disappointment by starting off with the gearbox instead of the DD. WELP I’m off to the river to race some A/C race boats.