USMTS Engine Size

[LateModel B23]

The July edition of Speedway Illustrated has a article - more like a infomercial - on Roush/Yates USMTS modifed engines. It does a fairly detailed listing of the components used like Little M block, Callies crank, Carillo rods, JE, etc. Nowhere does it list the size(s) of what is being built or what is most commonly going out the door.

One time it says "Since the engine is a stroker........" But, nothing more about what stroke.

Any ideas? I am sure a minimum on bore of 4.125, but 3.625? 3.75? 3.875? 4.00?

[02mod]

Its says in one of the captions, the engine is a 420 & that by the rules its restricted to 8,400 by usmts

[LateModel B23]

Okay thanks, I see that now by the distributor description. So I am guessing 3.875 stroke.