Yeah, here comes the avalanche of personal preferences....You are going to get a million opinions. I always just use conventional 10W30 in most of my cruiser/street cars. Whatever is on sale. Never any issues.
No need for synthetics. The seal technology is not o-ringed like today's engines. The old school gaskets will have seepage with synthetic oils.
There's been a bazillion threads on this topic already.
I use Valvoline 10/30 Conventional with Rislone ZDDP. It has worked for me as well.Rick Ehrenberg says 10w30. I worked with a Ford power train engineer back in the 1990s and he said 10w30 was the best "one size fits all" for muscle cars and classic cars.
I've used high mileage 10w30 and a bottle of Rislone zddp. About half of the members here will disagree with this, but it works for me (so far).
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