At last the latest magazine arrived into my mailbox as well and what a nice history of the FH motorcycle.
The twin cam engine looks very attractive and I trust there's extra power compared to standard J model. As we all know the twin cams are very rare and expensive.
I've been thinking what are the real differences between the engines? It would be nice to upgrade my 1928 JD to the same power level as the JDH.
If someone knows the cam specs, is there any problem to re-grind the JD cam to JDH specs?
Also I would need to change the inlet valve springs, right?
How about the compression ratio?
Is the carb 1 1/4" or bigger?

I would like to hear opinions. Have someone else ever been thinking of this upgrade?