The Colemill Bearcat conversion for the Cessna 310R improves the
aircraft's performance significantly. The new IO-550A engines
improve single-engine service ceilings as well as improved rate-of-climb
and cruise airspeed.
A Colemill conversion is much more than an exchange for more powerful engines.
Colemill is concerned with all aspects of improving the performance of an
aircraft. A Colemill conversion is a fully integrated and practical performance
package, engineered to deliver satisfaction for the life of the aircraft.
Colemill has been converting all other Cessna 310s since the early seventies.
Since the Cessna 310R is already a good performer, we felt to improve the
Cessna 310R, we would have to come up with something very special.
What was needed was more power without any additional fuel consumption,
and a proven engine that incorporated the latest state of the art engineering.
The engine must have a TBO of at least 1700 hours and above all be reliable
and trouble free. Our research led us to the 300 horsepower Continental IO-550A
engine which met all our requirements and then some. The IO-550 was built under
the minimum horsepower rule, that requires the engine must produce at least 300
horsepower minus nothing, plus five percent. The engine has a different case
casting than previous engines and has additional hold downs on the cylinders.
So far, the engine has been the answer to the old case cracking problem. Colemill
has been using the Continental IO-550 engine on the Foxstar Baron since 1984 and
the owners have been very satisfied. Beechcraft started using this engine on the
A36 Bonanza in 1984 and recently announced it was going to use it on all new
Barons --- more reasons why we decided that this engine was the best one for the
310R BEARCAT conversion.
Our 310R BEARCAT prototype picked up an additional 14 knots in cruise and climbs
over 1800 feet per minute with both engines. This single engine rate of climb
was improved considerably and the single engine ceiling was raised to 10,400 feet.
Our research, found the three blade McCauley Propellers and Woodward Governors
work very well with the Continental IO-550A engine, so we use your propellers
and governors to save you money.
Colemill also offers complete interior, exterior and avionics packages to bring
your aircraft up to "almost new" and state-of-the-art in electronics.