motor mounts & bellhousing question

are the bellhousings innerchangable between the early flat head fours & the F heads fours?
How about the flywheels?
Do you have to modify the steel motor mounts on the frame or will the two motors bolt right up?
Thanks...Tom

 

I think everything is the same except for the CJ2A L-heads. They had a different mounting spot and used a lighter flywheel. I believe it was 1951 when Willys switched to the heavier one.

 

http://www.cj-3a.com/interesting_parts.htm engine mounts

http://www.cj-3a.com/Starters&Ringgears.htm fly wheels

 

Maybe someone more educated can confirm or reject this.

 

I shaved .280 off my flywheel (f-head) when I resurfaced it. I lost a little torque, but not enough to notice, It should accelerate faster, and be less hard on the clutch.

I lost 7 lbs on the flywheel taking that much off.

 

ring gear tooth count is different, some L heads use a starter that the end of the shaft goes into a hole in the bell housing, so if you keep the bell housing, starter and flywheel together, should be a bolt up deal AFAIK

 

yup. block design changed ever so slightly in '51.

it was smaller too, flywheel and clutch ( in the 2a)