Will HFC's crack without flex in the exhaust?
 

I'm thinking that if I was to install my Stillen HFC's there's a chance they will crack eventually, as there is no flex pipe exhaust and there's no mounting bracket on the stillen hfc.

What do you guys think? If so would using the exhaust bolts with springs after the cat help?

im running mine with fast intentions hiflows and stillen silver series ypipe no flex pipe anywhere. so far so good. but only have about 300 miles on all of it. but i do plan on getting a differnt ypipe with flex pipes.

Do you hear any diving board type of sounds when you are on a bumpy road?

I think cracking cats are a gamble.. i've seen some members crack and some havent.. i've had mine for roughly 8-9k miles and close to a year w/ no problems..

What makes them crack? Is it engine movement, if so wont the Stillen engine damper help. Just a thought.

The bumps on the road, makes the exhaust bounce as a whole, from the rubber mount to the flange on the end of the cat, which is supporting the other 1/2 of the exhaust weight itself... the shock and the weight might crack the weld in time.

nah but without that mount for support from the stock cats im thinking the stillen ypipe might not be the best idea, ill probably order an aam very soon.