A new exhaust system wasn't required for my Continental O-200, but one thing that my airplane needs is some cabin heat. Unfortunately, the old exhaust wasn't fashioned in a way that (easily) allowed for a heat muff. I did make a heat muff many years ago, but it was too small and didn't have enough capacity to produce hot air. It was lukewarm at best. The old exhaust was a "two into one" system on each side. There was a member at the Tailwind Group that posted a message stating the ideal exhaust length for a Continental O-200 was between 28"-32". There were follow-up replies to that message, but nobody disputed the claim about that specific length of 28"-32". Furthermore, I spent a fair bit of time googling and binging to find an answer to the "ideal Continental O-200 exhaust length" and there is NOTHING to be found on that subject. Seriously, nothing! With that in mind, I went ahead with the intention of making a new exhaust system that would be comprised of four individual pipes (aka "four into none") and each pipe would be the same length.
I have once again failed to take photos of this process!
Essentially what I did was cut the old exhaust off about 3-inches from the flange. That way I wasn't required to buy new flanges and weld new stacks onto them. Once I had the exhaust removed, I reinstalled the four short stacks and then positioned a crossbeam (red arrow) down below. Dave Sharp (from Sharp's Fabricating & Muffler) then measured and mocked up a system in which each pipe ran from the short stacks and exited at the same height just above the crossbeam.
Each pipe is 36" so I need to measure them all individually and come up with a uniform length. Once that is done I'll need to figure out how to make some hangers so they don't vibrate and crack apart. Stay tuned.