I've been using Castol 30 wt.

 

Mobil 1, syn. 0 - 40W.

Opps, forgot where I was. Use 20 - 50 GTX in my 84, 383ci.

 

In my 70 I used 10w-30 Valvoline, In my 00 SS and 01 GAGT I use 5w-30 Valvoline. For dirt track racing, I used 30w Valvoline.

 

Havoline 10w-30. Pretty much as basic as it gets.

 

Haven't changed the oil yet. Probably Castrol or Valvoline though... 30W or 30W-HD.

 

I used to run 20x 50 Castrol GTX, but I think on the new motor Im gonna go to synthetic

 

Castrol GTX 10-30 this season. Now that the engine has a few thousand kilometers on it I'll probably switch to castrol synthetic.

 

I currently run Castrol GTX 10W30 in my '02 Z28, but I also ran it in my '81 Z28 w/383. My dad uses it as well in his '73 Camaro! IMO, it's a good non-synthetic oil (so far, no blown engines!!).

I honestly don't know how to "compare" various oils in day to day driving, so that's why I've basically picked a good oil and stuck with it. I don't care to use synthetic either...........I put a lot of miles on my cars, so I'd rather spend ~$15 per oil change instead of almost $40 per oil change every couple months.

 

I have run the Mobil one syn. in my 96 Dodge Dakota 318 magnum since I bought it new and so far no problems with a little over 70000 hard miles. I broke in my camaro's 383 on castrol 10w-40 and have since changed over to Mobil One syn. after 3000 miles.

 

For my everyday vehicles I'm using Castrol 10W30 during the summer and 5W30 for the winter. My 86 TA has castrol 10W40 in it and in our 67 race car we use Castrol Syntex 5W30 or Mobil 1 synthetic 5W30. I tried Valvoline back in the 80s and I kept getting a white waxy substance in the lifter area so I stopped using it and will never use it again.

 

Quaker State or Mobile 1 20-50 in the Chevelle 383

 

I'm running Castrol Syntec in my 454. It looks like new after 5000 miles compared to the Mobil 1 that I used to run in my old 93 Z28. That would change color and get dark within 1000 miles.

 

Valvoline MaxLife 10W-30