I was impressed with these....
Ribs were used through out for heat transfer
Cheers,
J
Damn, those are WAY too much work! Modifying the stock (German) ones is
much easier then starting from scratch. You can't use the stock fins in any instance due to the shape they are inside, but there are many other ways to add fins for heat transfer. I think a variation of the 40hp boxes would be simple and effective. I didn't build any 40hp style ones, but I would give it a thought before doing anything too drastic. Less work in the end.
Andy