Valve guide seals LA 318 ?

What RRR just said--
340s no SBM came with Dual Counterwound interference fit springs or dual with a dampner between the coils
The hp cams had a red single spring with a dampner
a good spring
and cheap but will not take much lift
I usually use a dual spring and set it up tall if a mild cam
the installed height of a SBM is short- so are Pontiacs and many other motors
BBC and BBM springs have wide availability and choices
Isky 6006 work, lots of choices
Looks like I get to learn beehives, back when they were introduced I let my customers be guinea pigs and do not really remember what they made work (or not work)
stem seals should be the same
but umbrella seals do not work with the real dual springs and you have to cut the spring seats with very few "drop in" exceptions- which are clearly stated tlll you tear down an unknown build
that raised step is what locates the single spring
do not count a flat dampner as a spring