I talked to redline performance engineering, and asked if I would need collector flanges welded onto the Pacesetter LT's if I bought them. He said:

"There is nothign to worry about with those. The y pipe is flaired
for a slip fit design. The y pipe fits over top of the collector.
SO if installed properly you will not have any leaks."


What do you guys think? Do you think it won't leak if I clamp it?

 

you should be fine if you tighten it well enouhg

 

I would have it welded, not clamped.

 

if your going to have it welded, you might as well just use flanges

 

I've got clamps on my 4" exhaust and no leaks. A properly done clamp isn't going to leak.