I'm installing some GSC S1 cams into my car. I have them pretty much in there. My problem is the 12mm bolt I took out of the CAS is too small for the GSC cams. Was I supposed to get something else from GSC to make these work? The tread pitch in the new exhaust cam is a 17mm instead of the 12mm that came stock. You can see my factory pick up for the cas has a 12mm bolt hole in it. And the end of the cam in the lower picture has a 17mm bolt hole :[

 

No , should be a drop in install. Maybe check the part number on the cam and be sure its not a Evo 9 intake camshaft.

 

I managed to figure it out. The pickup in my cam sensor needed to be bored out to the larger 12mm bolt diameter and I picked up a nice grade 8 allen head bolt to use with it. After that it worked perfect!