I've talked to several people who said they know---they have said that
"Regular" grade gasoline is acceptable for R2 Avantis since they have a
fairly low compression ratio.  Also, they have said that I whouldn't
worry much about unleaded gas in an original '63.  Any comments.  For
the difference in price and how much the car is driven, I would just as
soon run premium but maybe it is a waste.

Mike N
---------------------------
   If you are running the blower even modern premium is marginal in an
R-2. The supercharger raises the effective compression ratio to at least
the R-1's level. If you start to pull any boost on regular you'll get
severe detonation and could do some real damage.
-- 
John Poulos
---------------------------
Premium fuel is not a waste for an R2.  An R2 has a conservative
9.0:1 static compression ratio which, by itself, might permit it to run 
on 89 octane.  But add the supercharger and the actual working
BMEP (brake mean effective pressure) within the cylinders exceeds
what 9.0:1 for a normally aspirated engine could produce; it is more
like a 10.75:1 compressioned engine under boost.  

R2 pistons are also cast, not forged, from Studebaker and they will
not survive long under conditions of severe detonation.

My R2 is run on 92-93 octane; the cost differential between it and low-test
isn't worth a broken piston.

Finally, unless you run your car hard when you drive it, you'll never experience
any appreciable valve recession, so leaded fuel or hardened valve seats are
unnecessary.  This isn't necessarily true for other brands of engines, because
of the relative hardness of Studebaker's cast iron compared to theirs.

Thanks,

Chris
---------------------------


---------------------------


---------------------------