Group,
I've just taken receipt of my 70 SS, and now am in the process of determining what has already been done and what needs to be addressed first.
Engine oil is one of my first priorities, and as mentioned in a pinned thread here for engine break in, the ZDDP (zinc) additive that was prevalent back in the pre cat converter days with pretty much any motor oil has pretty much gone bye bye. Now days it's high detergent, no /low ZDDP, and a move to synthetic/blends.
The newer engines with roller tappets do not need the additive, but our old original flat tappet motors do. The ZDDP creates a sacrificial barrier between the cam and lifter. While it's critical for engine break in, the additive also is being recommended now for every oil change.
1 common fix is to go with Delo or Rotella diesel oil as they have that additive. As I'm researching though, I'm finding that those oils are also high in detergent, which washes away the ZDDP. Some simply add a container of cam break in additive to pick up that additive. I'm finding now though, that break in oil additive also was low in detergents, to help rings seat. Great for break in, but I don't know that thats a great idea for every day use.
Racing oils tend to have the ZDDP additive, but then they also have a higher viscosity, which can increase oil pressure. I don't know that a significant increase in pressure is good for the older engines, but then again I don't know that it's not. Just thinking oil leaks might become more common.
I found an interesting read on a corvette forum ( http://www.corvetteforum.com/forums/c3-tech-performance/2484100-list-of-flat-tappet-oils.html )
My question to all of you is this:
Which oil do you run? weight/brand/name
Do you use a ZDDP additive?
Any other thoughts that I'm missing?
