Dual valve springs stock on 2.02 915 J Heads?

Cudafever said
Yes.
But you must have a single groove valve stem to us it. stock chry valves are 2 or 3 grove valve and keeper style.
In other words, you would need to buy all new valves to go with a single groove lock/keeper

Ok, don’t want to buy all new valves :)

So I need to buy 2-3 groove keepers? Or is there some special formula that I don’t know about?