[Chad Rhodes]

Originally Posted by Alan Roehrich

After working with several people who had the DLC fail on tool steel lifters, when used on cast iron core camshafts, I spent a few hours speaking with several DLC applicators, including three who coat tool steel lifters for various vendors. Every single one of them stated without reservation that their DLC coating was completely incompatible with cast iron camshafts. Their position is that the rough abrasive nature of cast iron will always cause the DLC coating to "spall".

One of the DLC applicators said that it was possible to run DLC on tool steel lifters against a cast iron core camshaft, IF you also coated the camshaft, and used certain brands of oil. They wanted $1500 to coat one camshaft and one set of lifters. They refused to offer any sort of warranty that it would actually work. One of their representatives did however claim that there would be a gain of 30HP in a flat tappet Stock Eliminator engine from coating both the camshaft and the lifters.

There are some people who are running DLC coated lifters on cast iron camshafts, you will always find some people who manage to do things that do not normally work. However, when the people who apply the coating to the lifters, and charge $400 or more to do so, tell you that using it against cast iron is a recipe for disaster, and failures are common, proceed at your own risk.

I've got a few piles of scrap parts that will verif this. Btw little flakes of DLC coating will wreak havoc on bearings.