RE: Rebuilding a 30 year old Dumas DV 40!
Exhaust systems: New and Old.
Nothing wrong with that old pipe, I'll save that for a future project. Back in the day, I wanted to squeeze all the power I could out of that old Fox engine. Now the engines are so powerful that is not a concern.
In fact I specifically avoided that new OS Turbo plug 0.21 Marine engine for this project. My son will be driving this (he is six) and I did not what a powerful high revving engine in this boat. There really is nothing out there in a low-revving recreational marine engine in the 0.40 size, thus the desire to use a converted aircraft engine again.