My machinist told me to use valvoline vr1 20w30 and I just want to make sure that the engine can handle a thick oil like that for 500 miles

 

NO!
VR1 has a high zinc content which can dramatically shorten the life of you catalytic converter.
Use a MINI approved oil and change it after 500-1000 miles (or however long you think the break in will take).

 

I don’t have cats…..🤣🤣🤣🤣 it’s a race motor and the exhaust is straight piped so I’m not worried about that I’m more worried about engine life than my cats

 

If you prefer, just find a high zinc content break in oil with a lower cold start viscosity spec. (10w30 or even 5w30) as long as it has a high zinc content for your break in period.
​​​​​​But honestly, the 20w viscosity spec shouldn't be a problem as long as your still in warm weather (above 70° or so), esp. with the extra zinc. Once the oil is above 110° the cold start spec goes out the window anyway.

​​​​​But do what you're comfortable with.

 

awesome then I’ll go ahead and run it with the vr1 for 500 miles I live in south Texas anyways so the lowest we get is like 50 degrees Fahrenheit so that won’t be a problem but thank you for the reassurance

 

South Texas...
No problem at all then.