[granprix]

We recently built a fully custom header/muffler combo. It's CAD designed and we were pretty stingy when it came to keeping tight tolerances with this system. We know the header is in spec (dimension-wise) but we have a strange exhaust tick that we can't find. Pulling the header back off shows a good seal on all six gaskets so no leaks at the exhaust ports, muffler seal is good too and no leaks in the welds or cracks. The tick is coming from the passenger side and almost sounds like it's coming out of the muffler.

We pulled the lower valve cover off and everything looks good and no pieces of head studs floating around. Haven't checked the top or the other side just yet but did do a compression check:

1 - 95
2 - 95
3 - 100
4 - 100
5 - 108
6 - 100

The car is an '87 930 with just shy of 50k miles. Drives great and pulls hard. I'm just a fabricator with limited experience on these cars an the owner (friend of mine) only has a decent mechanical knowledge of these engines.

Any help would be greatly appreciated!