Hawaya Racing has just released our new Stainless Steel exhaust head flanges for UPM heads. In the past, we had used carbon steel head flanges to build our headers, which worked well with carbon steel tubing, but no so good with stainless tubing. The different materials expand and contract at different rates which would cause cracking and eventual failure. These new S/S head flanges will be a great improvement over the Carbon Steel pieces.