I've been using the VR1 conventional.

I used to run Mobil One 15w50 synthetic, but it got to be VERY hard to find. The conventional VR1 I can get at any parts store around here. The synthetic VR1 isn't as readily available and in only one or two viscosities.

I've been running Lucas HotRod 10/30 for years in my solid flat tappet engine. I run 10/30 because my bearing clearances are more typical of a street engine than a race motor. I typically change it once a year, in the winter when I also do a valve adjustment. Important to note that my car sees well less than 1000 miles a year. So far so good.

As recommended by my engine builder (HPMIKE on this site). 20w50 vr1.
July will be 2 years it's together. I drive it all over, probably has close to 5,000 miles on it.

Another vote for the Valvoline 10W-30 VR-1. I can find at Napa for $6.99 a quart.

Ask machinists that are drag racers what they use. Joe Gibbs, Lucas, royal purple.

Always like Valvoline oil also, nice to have options.

With the results I've seen from using "normal" oils like Mobil One and Valvoline VR1, I've seen no reason to spend the extra money on oils like Joe Gibbs, etc.
If your oiling system is up to the task of what your engine needs, any good quality oil will work. Just my 2 cents.

10000000000%

Same hear as I run the VR1 conventional non synthetic and I just bought 7 qts the other day for $5.99 per Qt and Salvo's. Ron

I use Brad Penn 20w-50, usually get for $60 a case. $5 quart

Mobil 1 Synthetic. 5 quart container at Wally World or Amazon for about 25 bucks. Have used for many years....Multi years between oil changes for almost no annual mileage cars.

Run in engines with both flat tappet and roller cams Zero oil issues.

If GM says good enough enough for ZR 1 and Z 06 Corvettes and Porsche or Benz say good enough for them,,,who am I to argue with engineers that are far more knowledgeable and have far more on the line than I.

Just as asking the best beer, religion, political persuasion or perhaps hair coloring one might favor in a woman.

Uh, oh! When does the ground war begin?

Brad Penn

Conventional for me...Joe