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jtrains
09-20-2009, 07:25 PM
I just posted a question about the strut. It was answered very quickly. Thank you.

I have another question about getting the proper prop.

The MC manual sais that the 2004 x-30 should have a LH 14 by 20 prop. That is easy to follow except I am putting a different size motor and transmission.

The original motor was the 350 with a Hurth 1:1.5 trans.

I am replacing the motor and trans with a big block 454 and a Velvet drive 72 or 71 model trans. I belive it is a 1:1 ratio.

The question is should I keep the recomended 14 by 20 prop size and angled prop or

down size the prop and angle for the bigger motor and 1:1 trans ratio.

Any info is greatly appreciated

Jim@BAWS
09-20-2009, 07:36 PM
I just posted a question about the strut. It was answered very quickly. Thank you.

I have another question about getting the proper prop.

The MC manual sais that the 2004 x-30 should have a LH 14 by 20 prop. That is easy to follow except I am putting a different size motor and transmission.

The original motor was the 350 with a Hurth 1:1.5 trans.

I am replacing the motor and trans with a big block 454 and a Velvet drive 72 or 71 model trans. I belive it is a 1:1 ratio.

The question is should I keep the recomended 14 by 20 prop size and angled prop or

down size the prop and angle for the bigger motor and 1:1 trans ratio.

Any info is greatly appreciated

Your putting in a 1:1 tranmission in an X-30 that is designed for a
V drive 1.52 to 1.0

Bad move there

Jim@BAWS

jtrains
09-20-2009, 07:40 PM
I'm putting on the bigger motor and trasmission because of the excellent deal that I got on the motor and trans. I got the x-30 as a project with out the motor and trans, that is why I'm putting anything at all.

How is it a bad mover? If the prop is resized and still a LH turn will it effect the performance?

EJ OJPROP
09-21-2009, 07:25 AM
The 1:1 gear ratio will not have the low end power that the gear reduction transmission provides. You will need to run a 13" diameter prop. I would do do what I could to keep the gear reduction.