Is there any reason not to install 3/8″ exhaust stud in lieu of the 8 mm that seem to sheer off. Are there higher strength 8mm studs available?
[Response] Stainless studs are an excellent idea for aluminum heads. Try to find a local fastener supplier that offers high-strength metric studs (8mm x 46mm: (std pitch, 1.25mm), 45mm long with approx. 15mm thread on one side (head side), 25mm on the other and 5 mm of no thread.). They are hardened to 10.9 grade. Always use high-temperature nickel-based anti-seize on all studs. Search yellow pages under nuts & bolts. [Response: Jeff] Open up the manifold holes and the holes in the head. Retap the head for 10m-1.5 size bolts. Use 10mm Allen Head Cap Screws to secure the manifold to the head. You will have to open up the holes in the gaskets as well to make them fit. This is about as bulletproof as you can get. [Paul Seminara] I do question the use of socket head cap screws….I don’t know if these are that great of a choice for this application since they are weak at the head. [John B] Almost any stainless alloy is going to be weaker than a good steel alloy…it’s only advantage is it’
