Is 20W-50 too heavy for my 340?

Wreck0nin said
I just changed my 360 out from 10-30 to 20-50, oil pressure with the 10-30 would bottom out in gear when warm, now I hold steady at 10-50 pounds idle to under load. For reference its a mostly stock 1973 360 that as far as I know hasn't been rebuilt, so my guess is the bearings are pretty loose. It just depends on how worn the engine is, but if it's mostly stock I'd say your fine, especially with the Temps your working with
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On one of my older 340's years ago, I ran 10W40, to 100,000 miles, then changed to 20W50, until 175 miles, then went to 50W, until I blew it up. By changing the oil viscosity as the motor aged, it kept the oil pressor up as needed. The reason a good oil gauge is important. I run 20W50 on my other 340's I use today. They have around 75,000 miles on them.