Triumph Repair: 76 Spitfire, castrol gtx, high compression

Question
I'd like your recommendation on the best oil (make & grade) & gas (octane) for a
76
Spitfire.

Answer
Oil?  Castrol GTX of course!  Grade depends a bit on engine condition and your local temperatures.  If the engine is still tight then 10W40 or the heavy duty 15W40 should be fine.  If you're in Texas with 100+ temps then you'll definitely need 20W50 for summer day time driving.

I've found Bardahls "No Smoke" to be effective at keeping the car looking environmentally friendly looking.

As to gas?  I like BP, but mainly it's for the British connecction.  The 76 should have been a "high" compression 1500 if it's still the original engine with correct pistons.  Mid-grade should be adequate unless it's pinking (pinging) under load, then step it up to the premium.


Cheers,

Jim