Outdrive Ratio

[FreeBeeTony]

Is it OK to use a 1.50 ratio with a 6 cyl? I know the ratio should be 1.65 but I found one really cheap and was wondering if it would be OK. Maybe with a different prop pitch?

 

[Trent]

Re: Outdrive Ratio

You will not be happy with performance if you do it.

 

[FreeBeeTony]

Re: Outdrive Ratio

How is the ratio determined? If the prop turns once for every 2 engine revolutions, is this a 1.5:1?

 

[Bondo]

Re: Outdrive Ratio

NO, That'll be a 1.98/1.....<br />2 revs/ 1 rev...<br />You need a 1.84/1....<br />the 1.65/1 is for a V-6, Not the I-6....

 

[FreeBeeTony]

Re: Outdrive Ratio

Bondo, are you sure the ratio I need is a 1.84:1?<br />I have been told in the past the IL6 used a 1.65:1. Also, would the 1.98:1 be close enough to the 1.84:1?

 

[Bondo]

Re: Outdrive Ratio

Tony,<br />I posted this for you on a previous post of yours.....<br /><br />1.98/1 for I-4s, 120hp, 140hp....<br /><br />1.84/1 for I-6s,+ sometimes the I-4, 470 mercruiser...<br /><br />1.65/1 for the V-6s...<br /><br />1.50/1 for V-8s....<br /><br />There's about 6" of prop pitch between the ratio steps.... So, It is possible, Sometimes, to use the Wrong outdrive,+ make up the difference with the prop.... IF you can get the prop pitch Needed....