The International Cessna^® 170 Association

Has anyone seen alternate exhaust systems for the O-300?

Other than the bartone tailpipes, I have been unable to locate anything beyond the OEM parts.

Would a Maule M4 exhaust fit the C170?

Rocking the Nation ?

Any mufflers other than the original pancake mufflers and the Hanlon Wilson would need approval. Would a Maule system fit don't know, never seen it done. could you build your own exhaust? Sure. But here is that approval thing to overcome.

FWI the Bartone or Benham pipes are only that, exhaust pipes, not mufflers.

When rebuilding my project I purchased a engine [O-300] with exhausts fitted and was told it was the same set up through all the models of cessnas of that era. This engine came off a Cessna 172 A model . The paper work for engine fitment and prop was completed until the cowls were to be fitted. Bottom cowl would not fit and many new swear words were used that day.
It was at Oshkosh when looking at a Cessna 170b when the penny dropped that the diameter of the mufflers were different .
So a engineering order was raised to fit the mufflers[fitted to 172a model] to the 170a and modify the cowl. So I had now lower blisters on my cowl. I have now seen 2 other Cessna 170,s fitted with the blisters on the lower cowl.
I will look for the engineering order [done 20 years ago] and see if it can be used on other Cessna 170,s .
However after that experience I would buy new correct muffler system with paper work. In my country there wasn’t available any thing new or second hand that would be legal.

Keep in mind that the early “pancake” style is not to be mixed with the later Hanlon Wilson style exhaust system. When replacing pancakes...replace BOTH sides completely.

The early airplane is converted to the Hanlon Wilson style by using two LEFT mufflers rather than the right muffler PN used on the 53/later B-models. (The ‘53 B-model introduced increased cabin heating and used a different right muffler.). The rest of the mod uses the correctly specified matching hardware as shown in the IPC.)

172 exhaust systems do not fit a 170 cowl as mentioned by Ozzie. Blisters are ugly IMO, and there are other issues when swapping FWF complete assys from a 172 to a 170. (One example is the oil gauge rod/dipstick will be incorrect due to the stance of the airplane.)