wrote in message
oups.com...
What exactly is involved in converting a 1989 Force 9.9hp (model 92F9A
Serial 1097) to a 15hp?

First, is the bore stroke the same?
Head/compression ratio?

Carb?

Timing?

Any comments?

Thanks,

Marko

Get a service manual for the two engines you mentioned. The specs will be in
there.