The notches look cast not machined. I measured the
piston above the top ring along the length of the pin
and perpendicular to the pin. The piston was a bit out
of round but I heard somewhere that they are supposed to
be a little bit oval to compensate for uneven thermal
expansion. The other set of pistons (Jahns) came out of
a different motor. I have the head that came with the
Jahns pistons. The combustion chambers look like they
have been ground upon. It has a B-cam. I think I will
clay the piston. This is done without a head gasket
right? What is the minimum clearance? I think the Bob
Sharp book says .008"
Thanks
NT
> Some of the aftermarket pistons have a small notch (looks like a
> 3/16" chunk carved out) machined on the top forward periphery of the piston.
> I think it indicated the front side of the piston so the notch would be
> toward the front of the engine.
> !!Don't quote me on this cause it has been a while since I have seen
> any like that!!, but I do remember such a set. Does this sound like
> what you have?
>
> Jim
>
>
>
>
> Gordon Glasgow wrote:
> >
> >
> > There shouldn't be any notches on the pistons. Do they look machined?
> >
|