Jump to content

Recommended Posts

The attached photo shows the muffler pieces as-received with my ca. 1912 Little Giant bus. The four shells are 4, 5, 6, and 7 inches in diameter and 20 inches long. The exhaust enters the inner shell through two 1 3/8" diameter pipes (one from each cylinder) and gets from one shell to the next though nine 3/8" diameter holes. Doing the math, that's 2.97 square inches inlet and 0.99 square inches outlet. Having no experience with this type of muffler, that seems like a LOT of restriction. In my case, the engine is a 2 cylinder, 5" bore and 4" stroke which works out to 157 cubic inches.

Does anyone know how this type of muffler is supposed to work, and how the hole size and number is determined?

Thanks,

Wayne MacDonald

post-61665-143138548165_thumb.jpg

Link to post
Share on other sites

I really think it should be the other way around. I have owned many autos and all of them had larger exhaust pipes than the tail pipes. Some authoritys may comment but I believe backpressure has some cooling effect on the engines exhaust valves. Look at the millions of model T Fords all have a larger exhaust pipe than the little tail pipe.--Bob

Link to post
Share on other sites

Mufflers kind of average the exhaust, it comes puffing down the exhaust pipe from the cylinders and gets smoothed out to a more even flow out the tail pipe. The exhaust pipe gets sized for the puffs and the tail pipe sized for the averaged flow, hence smaller size. At least that is my story and I am sticking to it!

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...