VR-1 (Valvoline Racing oil), though high in ZDDP, is not intended for long, or even moderate drain intervals. It's a RACING oil, which means you run it-drain it. Its additive package is designed to work fast and furious - and be depleted quickly, which makes the oil a poor choice for cruiser motors.
The Delo 400 Multigrade SAE 15W-40 (API CI-4 PLUS) is a great oil for older flat-tappet gas motors, but the trouble is, it's F$!*%%@N' impossible to find, unless you have a fleet-lubrication sales place or farm/tractor supply near you. Out here in So. Kali, only thing avail is the 400 LE.
To kind of get around this, I run 6 qts of Rotella T, and BAM! - I kick it up a notch with 2 qts of VR-1 just to goose the wear goodies a bit. Drain at 3-5k miles.
Other thing is to buy some of the boutique oils ($$$) or diesel-rated amsoil prods
The Delo 400 Multigrade SAE 15W-40 (API CI-4 PLUS) is a great oil for older flat-tappet gas motors, but the trouble is, it's F$!*%%@N' impossible to find, unless you have a fleet-lubrication sales place or farm/tractor supply near you. Out here in So. Kali, only thing avail is the 400 LE.
To kind of get around this, I run 6 qts of Rotella T, and BAM! - I kick it up a notch with 2 qts of VR-1 just to goose the wear goodies a bit. Drain at 3-5k miles.
Other thing is to buy some of the boutique oils ($$$) or diesel-rated amsoil prods