With my first B, I used Pennzoil, Havoline, Valvoline or Wolf's Head straight 30W. Auto-X'd about every other weekend... On one oil change interval I couldn't find those lubes so went with Q-State. First run thru the course, I pulled the dipstick and it was FOAM!!! Ended my day and I never used THAT stuff again. I know they've changed, now are owned by Pennzoil but it's a deep-seated prejudice. /ubbthreads/images/graemlins/devilgrin.gif
When anyone asks about "additives" my Standard Response is: "Yeah, sure. Pour it in there... you don't plan on ownin' that British-hit-box for more'n a few years anyway, right? Let th' next poor schlub worry about it."