[blykins]

I think a lot of the failures come from the use of an aluminum chain tensioner. They will directly cause chain failures. There have been several "upgrades" for the SOHC engine and a lot of nice parts have come out lately. Robert Pond is making a ductile iron tensioner which won't flex like the aluminum one and there are some new chains and gears out there as well.

Robert has done some Spintron testing as well, while he was R&D'ing his own SOHC heads, which helps with valve spring selection...