The aftermarket pipes pointed out above are better than a stock pipe. I am not sure the exact increase in power some are made to do different things. The klemm was A high rev pipe. The bills, dynoport and DG I believe were an overall pipe. Not sure on sprock and powerpros. The stock pipe has been proven to make better horsepower then the FMF.
I just received this email from JEMCO about a pipe for the T4. I had them build me a pipe for my 84 T3 which I could not be happier with.
Joel, I do build a system for the Tecate 4. It sells for $275.00 + $30.00 shipping. Delivery is 2-3 weeks after pre-payment by money order. Give me a call at the shop to discuss and place your order. Thank you for your inquiry.
I do not have a pipe for the T4. I had Jemco build me a pipe for my 1984 Tecate 3 last year. I just picked up my first T4 and figured I would check with Jemco to see if they have ever built a pipe for the T4. I will check with them and see if they have any pics of a T4 pipe they built before.
Yes the expansion chamber. To me the exhaust system has two parts, the pipe (expansion chamber) and the silencer (silencer and mid-pipe) I am in snowmobile rebuilding mode and I use the term pipe often. Here is some pics of my Jemco expansion chamber for my 84 T3