You need to contact a Corvair Club for an answer from people who really know, based on experience with this engine. I would probably use 10w30 but you may need to use 10w40. I am not 100% sure on this engine.
10/30
how much oil does an yamaha xt500 take
Most Pontiac engines will take around 6 quarts of oil....with a filter change.
A Pontiac engine will usually take close to 6 quarts of oil with a filter change.
A Honda CT110 will take 0.9 liters of oil
it should take 4.7 quarts with oil filter
10L
How much oil in a 7.5L 460 engine? It is in an RV
how much oil dose a 1.6 suzuki vitara take
4 quarter of oil
1 liter