Perusing through a Summit Racing catalog I see an engine break-in oil additive with Zinc & Phosphorus added. It's recommended to be added with each oil change, and the last oil change I did was with Mobil 1. This being my first street/strip engine, I wonder if it would help if I added this stuff on future oil changes, or maybe just the next two? I have performance parts in my engine, rebuilt by the previous owner, with about 6k miles since then. I firmly believe in frequent oil changes on ALL vehicles in my stable, & this additive seems logical for my Z28 but I'm not a chemist. At 6k miles, 6 passes @ the track, & a couple of "highly spirited" drives home from work I figured she's "broke in" by now.

 

Not needed with a roller cam.

 

Yep - not needed. Only for flat tappets.

 

1994BmtZ28:
Zinc & Phosphorus are good high load additives but are poisions to catalytic converters which is why modern oil formulations don't use them. Differential lubes do but there are no converters to worry about.

 

Good to know fellas. Thanks for enlighteneing me.