He could be right, that the latest API service ratings have adjusted the detergent (vs. ZDDP) additive package to a balance that is no longer harmful to flat tappet camshafts, but I'm not ready or willing to trust it. I've been using Valvoline VR1 high ZDDP formula in my FT engines ever since the mid-late '00s when it became obvious that the API oils of the day were causing FT camshaft failures, and I've had zero problems doing so. I really can't see any good reason to switch to a regular OTC oil in my dinosaur engines at this point - those "normal" oils might be fine now, or they might not, but why take the risk?

 

My late neighbor had a dozen old collector cars and bought zinc additives for all of them. No harm right? I followed that advice with my 1987 SS Aerocoupe and 1974 AMC Matador X and no issues. Cheap insurance.

 

if you watch the ...oil guy....he does NOT recommend using a zinc additive....he tells you to use a oil that has the extra zinc in it

 

Another internet expert. I listen to the guys that actually own the cars, and have for decades on end. I think the companies that make the additive would disagree as well. I never had an issue and I'd like to hear from someone that actually did have an issue that was caused by a zinc additive. I would listen to someone like that and take it into consideration.

 

Lake Speed Jr is a TRIBOLOGIST ....an oil expert....so he just might know what he is talking about

 

Modern SN rated passenger CAR motor oil is Very Very good- for Modern passenger car engines.

If you are running flat tappet equipment from 3 generations ago, use the correct oil with ZDDP.
VR1 is properly formulated for this application.

 

My thoughts as well.