2:1 vs 2.3:1 belt drive

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2:1 vs 2.3:1 belt drive

Post by crazycoonass »

Just curious about which performs better. Pros/cons. Good/bad. Whatever. Just looking for opinions. I have a SBC 560hp/560t. Currently running 2:1. 78'' whisper tips 2.0 on a 15x7 aluminum hull if any of that matters. Thanks for any input.

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Re: 2:1 vs 2.3:1 belt drive

Post by BenBad »

I think you will like it. I went from a 2:1 to 2.4:1 and do not regret it one bit. I had a 76 inch "R" 2 blade prop. I ended up needing to a 3rd blade. With the 2 blade fully pitched when I stood on it it would instantly max out on RPMs so I was loosing a lot of push. I am now pitched about 2/3rds the way out with the 3 blade "R". I just had one more blade made to match my other 2 I already had. I have a SBC 465HP/470t.
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Re: 2:1 vs 2.3:1 belt drive

Post by RJC5778 »

all depends on how you use the boat and how the set up work IMO. adding more gear is better on the lower half of the boats performance curve IMO. like 3.73 gears to 4.10 in a truck, more gear more get up and go, roughly the same here (pushing air not tires to pavement) more gear allows for more pitch. look at the sweet spot of your blades and try to achieve max efficiency at that blade speed and angle of attack. i thought about switching to a 2.3:1 (14x7 robichaux - 540 BBC 2:1 3 blade NGR 80") keep the same blade but able to pitch more, im currently at pitch mark 2 with this set (alot of motor roughly 650hp and TQ) so im getting more push by having a large motor. i think it would benefit you being you are from Louisiana and we do alot of running shallow, heavy, and dry ground running down here. like i said all depends on the boats intended use. trade off get up and go for go and gone. tractor or truck

i stuck to the 2:1 cause the boat does everything i need it to do and then some by brute force. i may be wrong above but it opinion right??? lol

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Re: 2:1 vs 2.3:1 belt drive

Post by barhopper »

I don’t have the motor numbers you have but on my 16x7.5 GTO I put the 2.3 on it and it was night and day difference to the 2 to 1. If I knew what I know now back then I’d go with the 2.5 to 1

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