Open Modified Tecumseh Motorsports

racerx427

Member
Looking to make my Motorsports H50 into a open modified. The stock stroke is 2.500", I'm lookin to get a 2.702" piston to make 14.335 cubes. I know the crank journal will need to be ground down and piston cut, to exactly what I don't know. What Piston and Rod will work to make this?
 
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The deck height is very close to that of a 5 hp flathead briggs. So piston and rod combo will be the same.
I built a 3 inch stroker into a 6hp tecumseh block. Used the same rod and piston family as the one I built in a briggs block. Cut the top of the piston for proper popup. Of course, I used commonly available briggs crankshaft and made a spacer shim to put tecumseh cam drive gear on.
 
I had good luck stroking the techumseh cranks, 2.6 - 2.7” stroke (since the journal was getting cut anyway to the Briggs size) and the using available pistons(for the Briggs)
The H50 stock bore is a .060 over compared to the Briggs IIRC

only issues with the H50 was breaking lifters, but that was before I found out there were billet lifters available.
 
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