My 1966 150F with a 150HP conversion had a true airspeed of 110kts. at 8000 feet when turning 2650RPM and was burning 8gph.

A 150 with 150HP is faster than a stock 150 but not what I would consider a fast airplane. I did the 150HP conversion for better high altitude performance. The Del-Air STC allows for a 10% gross weight increase. About 100lbs. of that was lost to the heavier engine and propellor.

David Rowland 7CO0
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