Expansion chamber wizzard

[karthead]

I need an expansion chamber wizzard or similar to answer my question.
I have a Yamaha IT250 motor in a go kart I built. The engine didnt come with an expansion chamber, so I went to the only motorcycle wrecker in my area which had only one IT250 pipe which was totally butchered. I reluctantly bought an expansion chamber from an IT175 which was a fairly similar shape to the 250, after they told me it would definitely work.
What do you guys think? Performance wise, will there be any significant difference? Am I better off with a pipe from another model 250?
Cheers!

[sickpup]

Yes.

[karthead]

[A100man]

Expansion chambers have many critical dimensions to work correctly, Header length, stinger length cone lengths and diameters etc.. etc.. they need to be tuned to teh port timings of the bike to get optimum performance and the carb tuned to suit.

A generic chamber will probably work to some extent but if you're looking for top performance get something custom made.. Expect to pay a couple of hundred for a single pipe.

[karthead]

That makes a lot of sense. I know expansion chambers are highly specific to an engine, that's why we went with the one that was similarly shaped to the one that was on it before. I guess its better than nothing! Perhaps when I have the resources I could attempt one myself. There are equations out there that determine all those dimensions of the chamber aren't there?

[A100man]

[karthead]

[c_dug]

How butchered was the correct one?

It'd surely be easier to weld a few patches into a proper pipe than to try and design your own.
____________________
I am a bellend, I am a man of constant sorrow, I am a gummy bear, I am a rock.

[karthead]