Originally Posted By Heinz
Craig, I think your subject is very important. If the Sigma has a leaky exhaust and no matter how low it is, it loses a lot of power at high revs. I had exactly the same problem as you have today for years. The notches on the follower tube were cut too long. No matter where the exhaust clamp was fixed, it remained leaky.

I'll take pictures of my solution tomorrow. My local exhaust guru, who also built the manifold for me, replaced all connections with flanges. First without gaskets, which was not good but now with additional gaskets. I can highly recommend you to replace the pipe connections with flanges. Only if everything is really sealed the Sigma engine has full torque and full power at high speeds.


Thanks Heinz

Craig Jezz