Topic: Crank Swapin'

[Mowindown]

Does anyone know if a 25 series crank (I think thats what it is a 11 HP) will fit into a non AVS 31 series block.  I heard talk on here about putting a 25 series crank into a 28 series block.  I have run into the problem of to many cubic inches for my class I race in (dang rule changes).  If the swap will work how many cubic inch would the 31 be with the 25 crank.  Thanks in advance.

[Don Gienger]

HI,
If you are looking at lowering your CID why not just go with a 28 OHV Briggs motor. Shortening the stroke is really going the wrong way in this motor. I know we have talked before but the problem is this. YOu don't have a rod availible to make things match up.
If you have a CID rule and it is only 30 CID then 28 Briggs is the way to go. Briggs 28 is really 28.4 and a 31 is really just over 30 anyway. So you don't gain much.
Just a thought.
Don