The shortest distance between two points...

[Alvin A Klusman Jr (Torque)]

Terry, 

You are definitely correct that the rod is MC9 or newer.  47903, if I'm not mistaken.  This is not a pedigreed, factory built MC10, it is a clone, with parts from a variety of sources, hahaha.  It's been a learning experience.  

I understand your point that the centerline of the rod is constant.  I have assumed that there might be a tolerance range for the position of the rod's bore.  If a factory team engine builder was hand picking parts, what might he think of that one?  Good?  Bad?  Indifferent?  Go fish?

Torque,  

Good eye!  I hadn't even thought to inquire about a detail like that.  I saw that notch in the 3rd port area of the piston skirt, but I assumed it was for clearance in the area of the side cover's main bearing.  I've never thought much about it before, but is third port timing of much influence?  If it hasn't been 9-ported?  

Also, the piston is marked for MC6.  Any concerns or comments on that?

Kurt,

The piston markings indicate it is a stock bore (2.125) Mc-6 piston for a 1/8 (0.125) stroked crankshaft.   ( Bore 2.125 / Stroke 1.625 / 5.76 cid )
SO this IS a stroker piston.  Does your Mc-10 clone indeed have a stroker crankshaft (1.625 stroke)??  The piston is scolloped (probably a Moss ) so
that means the intake ports are effectivly raised from the stock location, without cutting on them. I'm sure that the exhaust ports have been squared,
(and maybe) raised. IF THE PISTON POPS OUT OF THE CYLINDER 0.0625 at top dead center it is a stroked Mc-10--IF NOT it is a stock stroke Mc-10.
If it is a stroked Mc-10, it will also have a head gasket AT LEAST 0.080 thou. thick or maybe thicker ( like 0.100 thou.or 0.125 thou. ).

The Mc-9 rod is a better rod-does not use thrust washers in the piston-has a smaller bottom end then even the Mc-10 stroker rod
( more crankcase clearance ). Also stronger!

Do you know how to use a degree wheel to measure the port timing of the engine?   You need to know when the exhaust opens--when the intakes open--
AND when the piston ports open (since the engine is not boost ported and is using the piston port intake).  Piston port timing CAN and WILL make a difference in how the engine runs when using the stock reeds and piston port type intake manifold!!


If you PM me your telephone number and best time to call, I'll call you and help you all I can!!  And give you my telephone number as well.

Best Regards,  "TORQUE"

PS--I'll tell you how to set-up the ignition on your Mc-10.  Set-up correctly it will run like a "Swiss Watch".  Done wrong and it will cause problems and blow condensers!!