Strongest engines:60's--->90's

KT Cummins
HP Range as used in production trucks: 400 - 600
Torque range as used in production trucks: 1,250 - 1,375 foot pounds
Bore and stroke: 6.25" x 6.25"
Displacement: 1150ci
Weight ~4,000-4,300lbs.
Arrangement: pushrod straight 6, turbocharged, optional aftercooling.
Approximate years of regular installation in commercial trucks: 1974-1985
Other applications for this series of engine: marine, construction, and general industrial use, including generators, pumps, heavy equipment, cranes, etc.
Variations found in trucks:
-KT-450 (factory ratings 400-450hp)
-KTC-450 (Aftercooler added to meet California emissions in mid-'70s)
-KTA-525 (Aftercooled, with same higher compression pistons found in KT-450s. Also available in a Formula KTA-525, designed to operate a lower RPM)
-KTA-600 (Aftercooled, low compression pistons. The largest factory setting KTs usually seen in trucks)
-KTTA-750 (Aftercooled low compression pistons with an industrial compound turbo arrangement [2 turbos]. The examples fo this engine found in trucks have been retrofitted. No evidence has been found of a factory KTTA truck installation.



cat 3408 450