stevebez

Any reason they are welded in and not installed with pipe / sleeve connectors? or even flexible connectors? Seems main reason these headers fail is that they are too rigidly installed or ?...??

skratch77

Mine only had to be welded to where you cut the cats out,they give you a middle piece that you weld on one side where you cut your cats off and the other side connects to the headers with 3 bolts and gasket.there is no direct welding on the headers at all.

skratch77

here is a picture to better understand.The only welding is where you cut the cats out

Worth the wait

I agree. They are great headers at a fair price, but I never understood why they don't just bolt to the stock cat and the downpipe (which would eliminate the primary cat) require welding

skratch77

after looking at the whole exh setup on the e55,the biggest bottle nech is where the cats connect to the stock headers,its a huge restriction there.

I can see why kleemann did it this way,it flows so much better but needs to be welded in place.

lowprofile

I believe Kleemann reported a defect in a batch of headers, in that they were not properly back gassed prior to welding. You have a good idea on using a flex joint. Even though that would reduce the stress on the header, I do not see that as the cause as none of the other header manufacturers require one. Keep in mind, a flex joint, while reducing the stress on the header, would also increase the stress on the hangers. Make sure they are up to the task.
I have had Kleemann, EC, FF, and MBH in my hands during the past year. Simply put, the Kleemanns appeared to made of thinner guage stainless. The overall feel and even sound was cheap.