David Bennett wrote:john2189 wrote:If you can get more power with the dometop pistons, why would anyone not use them when rebuilding and engine, even if you had to buy the head to match the pistons ?
how much of a differance is there between the domed and flat pistons ?
The 154 s had 15 Hp The older cubs had 10
It would cost a great deal to by all of the parts needed to make the change Carburator, manifold, cam, pistons, governor etc Then you would
be using a 50 + year old crank that wasnt designed to be turning the extra rpms
I put the doomed pistons in one of my cubs I did not have to change the head, has a little mower power in tall grass.
David
There were many factors involved in the increased power. Probably the least important was the pistons. They were mostly important because of their lighter weight, allowing higher RPM. The higher RPM was made possible by changes to the carburetor, manifold, and governor working in concert.