I just purchased a full 3" TBE for my 04 evo. Im wondering if I should alter my order to include a down pipe with a flex joint. What is the function of the flex joint? Is it necessary for fitment issues? Does it stop engine vibrations and movements from stressing the rest of the exhaust system? Do most people run a flex joint? I dont remember seeing one on my stock down pipe, so is it really necessary. I've searched but could not find anything. Thanks for any/all info.

 

Stock one doesen't have one so I see no purpose on having it.

I run RMR with no flex for 2+ years and no problems.

 

the only time i've heard flex joints required were when i was purchasing exhaust manifolds (300zx) they were supposed to relieve some stress of thermal expansion/vibration of the exhaust and make tubular exhausts manifold last longer. i don't see a benefit of such with cast manifolds. i've owned 3 turbo cars and none of them came stock with one.

 

so, it is not really a necessity when selecting a down pipe. More of an extra precaution....I take it.....anyone else have any input?