1964 CP77 Exhaust leaks

[Fastwater]

Hey All,
I recently purchased some repro pipes with new copper gaskets and packing. I am extremely happy with the quality and fit of the pipes. After I installed them I noticed that there was a little exhaust leakage from around the new rubber gaskets and a knocking sound while decelerating. Is any leak normal and is it causing the slight putter sound? Thanks for the help.

[allthumbs]

I've had the same sound for a while now. I have aftermarket pipes that are not air tight around the connections to the headers. some of the folks who know such things here swear its the air screw/idle screw combo on the carbs that is the prob. i keep playing around to find the right setting, no luck. I'm beginning to think that I need to rejet the carbs for the pipes, which are very unlike stock. I'm going to break down the carbs and do it at the end of fall if i can't get it figured out. maybe buy new mufflers