Summit Racing oil

I have 12 qts of the summit oil. 10w40. I bought it at a swap meet last year for 3 bucks a quart. I will use it in one of my engines.

With that said, Brian @ IMM Engines, who built my supercharged small block with a solid roller cam, only recommended 20w50. I know he did a few oil mods, and set up all the bearing clearances, so I will run what he specified for my particular engine.

I am curious to run a 10w30 or 40 oil though.