nine-44

I just pulled the head off my 951 engine today. I'm doing the head gasket and most of the external seals before the eng goes in. I wanted to go with the wide fire ring HG, little did I know, it already has one. It appears to have aftermarket studs as well, does anyone know how to visually ID the aftermarket studs? I'm basing this assumption on a lighter color than the stock ones I've seen, mild install marks that I've never seen on stock and a higher pitch ring of the metal composition. From the ring they give they sound pretty hardened(possibly a chromo ring). I've gone to school for welding and machine trades, so that's my experience. Thanks, Andy

Danno

Hmm, could be aftermarket studs. Raceware is plain steel that has a hard-coating, like nitriding. Black in color.

One way to tell if they're aftermarket studs is to measure the nut and thread-pitch. Both Raceware and ARP uses SAE threads and 12-point nuts instead of metric.

I don't know about pitch since you've got a fairly thick stud, which will always be high-pitched regardless of material.

nine-44

The color is light, and the nuts are 6pt. They look like stock but there is no corrosion whatsoever. May just be new stock replacements. Either way, there was no reason other than piece of mind to replace the HG. I'm not going too extreme this time around, and it would be easier to do studs in the car with the engine bolted down. Thanks