Classic 18 Duoprop swap question

[glenncal1]

Hello all-purchasing a 1971 18' which currently has a 270 single prop drive. Motor is a 351 Ford. I was thinking about putting a duoprop on it (might just do the lower unit, might upgrade the entire drive). What would be the better gear ratio 1.78 or 1.95? Thanks Jim

[ZXXX Donzi]

Originally Posted by glenncal1

Hello all-purchasing a 1971 18' which currently has a 270 single prop drive. Motor is a 351 Ford. I was thinking about putting a duoprop on it (might just do the lower unit, might upgrade the entire drive). What would be the better gear ratio 1.78 or 1.95? Thanks Jim

Why do you want to go to a duoprop?

[glenncal1]

More stabilty, better hole shot. Not set on doing it but I think it would improve the performance for water sports etc.

[Scott B]

The 18 hull runs well with a Blackhawk and a very high X dimension, but I can't say I have heard of one with the Volvo setup.. If you have the lower it would be a cool swap to play with, but if you have to go buy one I think I would have to seriously think about the cost vs value thing..

The other Scott B

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[onesickpantera]

Originally Posted by glenncal1

Hello all-purchasing a 1971 18' which currently has a 270 single prop drive. Motor is a 351 Ford. I was thinking about putting a duoprop on it (might just do the lower unit, might upgrade the entire drive). What would be the better gear ratio 1.78 or 1.95? Thanks Jim

My buddy has a Four Winns Unlimited which is a deep V 19 footer and he has a DPS drive. I know he runs F9 props and I am pretty sure his ratio is 1.78. I can find out if you want me too.

His boat has a great holeshot and a wicked mid-range for having stock power!