Originally Posted By: rrounds
It's a flat tappet engine, I would look at Lucas Hot Rod & Classic Hi-Performance Motor Oil SAE 10W-40.
p/2373
z/2045
I'd be a bit leery about putting that much extra zinc/phos into a vintage 1973 engine. I doubt the API SD/SE specs of the 1970's were anything near those levels....probably closer to 1200-1500 ppm Zn. And that can essentially be met using a current SL rated oil...such as the Castrol 0w-30 from just a couple years ago...or even some current SN high mileage oils with 1000-1200 ppm Zn. From what I've read, way too much Zinc can be just as detrimental as too little. In any case I'd do more research on the topic before loading up on Zinc beyond original factory specs.
It's a flat tappet engine, I would look at Lucas Hot Rod & Classic Hi-Performance Motor Oil SAE 10W-40.
p/2373
z/2045
I'd be a bit leery about putting that much extra zinc/phos into a vintage 1973 engine. I doubt the API SD/SE specs of the 1970's were anything near those levels....probably closer to 1200-1500 ppm Zn. And that can essentially be met using a current SL rated oil...such as the Castrol 0w-30 from just a couple years ago...or even some current SN high mileage oils with 1000-1200 ppm Zn. From what I've read, way too much Zinc can be just as detrimental as too little. In any case I'd do more research on the topic before loading up on Zinc beyond original factory specs.