MAC 4 into 1 on 1980 KZ550C Question...

Hi Folks, I have a 1980 KZ550C with only 7,000 miles. It runs great and I've had no real problems since purchasing it this Spring from someone who kept it in great condition. My question has to do with the new MAC 4 into 1 exhaust that I (started to) put on this weekend. I did use new copper gaskets and the new pipes seat up against them well, but the pipes don't seem to want fit using the two half-circle shaped pieces (are these called "C clips"?). Each pipe has two of them.

More info: The MAC exhaust comes with thin collars attached to each pipe. These collars are much thinner than the OEM collars on the original system. They aren't much thicker than a couple of quarters stacked on top of one another. They seemed so thin that I re-used the old collars and simply tighted the slim MAC collars over them. This seemed right at the time...but now I'm not sure. I'm unsure because the pipes didn't really fit using the "C-clips" when I did this. When I left the "C-clips" off, it when right together...but seems to leak air and is really loud. They say the MAC is loud but this loud?! I don't think I'm doing something right here.

I'm pretty sure I have to go back and use the "C-clips" but then I don't think it will all go together. What I mean is that when I used the clips and BOTH collars...I ran out of room to thread the nuts on. Do I just need to "jimmy" it some more? Or, should I not be using the OEM collars and just use the thinner collars already attached to the new pipes along with the "C-clips"? Note here: the MAC collars are fitted in such a way that they can't really be removed from the pipes, so only using the OEM collars by themselves doesn't look like an option. The only other answer would be that I don't need the "C-clips" and using both collars is correct..but I don't think this sounds right.

My sense is that there is an easy answer here that will save me a lot of time and muttering while trying to get it all to fit properly. Any help would be much appreciated. Thanks ahead of time!

Because of the terminology you are using, I am not sure what you are using. The end of the header that fits into the head has a small lip on it. You will use the two split keepers against that lip with the unflanged side toward the head. The cast stock mounting flange than fits over the flange of the split keepers and presses the pipe against the coper gasket and head.

Couple things

On the Mac system for my KZ550, I didn't use the split collars or the original flange plates. I used only the hardware that came with the Mac, plus the copper crush-washers.

Make sure the old crush washers are out of there. If not, there won't be a smooth surface for the new washers. It's real easy to leave the old ones in there because they look like part of the head.

Yes, the Mac's are much louder, and have more tendency to leak at the head since the hardware is thinner. You just have to be meticulous with everything and make sure the head surface is very clean and smooth so the crush washers seal well.