[pontiacphil]

My rebuild of a 1967 Pontiac 400 motor is nearly complete. Bored .30 over, crank turned .10, forged pistons, Crower cam kit, 3-angle valve job on stock #670 heads, forged CAT connecting rods, new Ram Air Restoration D-port exhaust manifolds, 2 and a half inch exhaust system using a true "X" pipe. Hope to have it in the car and running within a couple weeks. After it is broken in what is the best motor oil (brand & weight) to use? This is in a 67' GTO convertible, 400 tranny, not raced but driven regularly on short cruises. Probably drive it about 1,000 miles a yr. Live in NW Tn. which has moderate temps. Been hearing some horror stories about flat tappet cams wearing severely with the newer motor oils. Not enough ZDDP metals in them to act as a lubricant. Hope someone can tell me from firsthand experience with older Pontiac V-8 motors the best motor oil to run. Thanx.

 

[SANDU002]

I have been using Castrol 10w-30 since my engine was rebuilt last year. Living in Maryland, the weather is very similar to yours. I have almost 2500 miles on the engine. I suggest you change the oil and filter after the first 500 miles to get rid of any metal particles from the rebuild. After that just change before you bring it back out from winter storage.

 

[Steve A]

Shell Rotella T - full synth - 5W/40.

It is a diesel rated oil and has all the neat additives. Try it - you'll like it.

Also pretty inexpensive @ WalMart or Sam's.

 

[johnebgoode]

I always broke in my race engines with 20-50 on the dyno.....made 2 passes and drained it. Then I used Synthetic. Never an issue and bearings always came out like new after 100 passes.