Bob & Phil,
The 1976 owner's manual calls for unleaded gas for the 455 and an
octane of 87 (an average of motor and research octane) at the end of the
para on "fuel". We've used regular gas since purchasing the coach without a
problem. The 1997 average was 9.3 with 83,000 miles on the coach.
I switched to a 180 thermostat for a few years and back to a 195
after installing a good engine coolant temperature gauge. On a flat road, on
a warm day, at highway speeds, the temperature was 190 to 197 and on a hot
day climbing long grades, 210 - 215. Since the engine didn't stay under 190,
I felt the 195 was better to prevent sludge, get rid of moisture, and lower
emissions.
I have tried 12 degrees advance with good success, (8 is the factory
setting), this past year and have installed a spark advance adjuster but
have not driven the coach yet.
Al Hamilton
The 1976 owner's manual calls for unleaded gas for the 455 and an
octane of 87 (an average of motor and research octane) at the end of the
para on "fuel". We've used regular gas since purchasing the coach without a
problem. The 1997 average was 9.3 with 83,000 miles on the coach.
I switched to a 180 thermostat for a few years and back to a 195
after installing a good engine coolant temperature gauge. On a flat road, on
a warm day, at highway speeds, the temperature was 190 to 197 and on a hot
day climbing long grades, 210 - 215. Since the engine didn't stay under 190,
I felt the 195 was better to prevent sludge, get rid of moisture, and lower
emissions.
I have tried 12 degrees advance with good success, (8 is the factory
setting), this past year and have installed a spark advance adjuster but
have not driven the coach yet.
Al Hamilton
