GLADIATOR 344ci / 390ci

The AC-AERO GLADIATOR™ liquid cooled cylinders are a game changer for the decades of cooling challenges that have faced the GA market and aviators.

A complete kit that comes with AC-AERO Liquid Cooled Cylinders, Hardware, Plumbing, Pump & Pump Circuit. Wrist Pins. Choose AC-AERO liquid cooled cylinders for increased power and weight savings.

Increase your power

Liquid cooled cylinders offer a substantial improvement over air cooled cylinders in power output and wear characteristics. The Gladiator product line in addition also boasts substantial weight savings over the stock cylinder components. 

GLADIATOR™ 344ci / 390ci

Individually and custom built for each and every customer. We can recondition your existing Lycoming 320 & 360 engine and convert to a Gladiator 344ci / 200hp and Gladiator™ 390ci / 220-265hp.

Air cooled engines are usually run rich during take off and climb, it is not unusual to run some air cooled engines at BSFC’s of .65 and even more if turbocharged. Liquid cooled engines can be run at best power without the need to cool the engine with fuel. By running liquid cooled cylinders we can close up the tolerances and thereby reduce blow-by gases and harmful emissions, at the same time realizing higher output due to better detonation margin.

Advantages of liquid cooling:

  • Increased power output
  • Lightweight design
  • No airflow and baffling cooling difficulties
  • Uniform cooling, no shock loading
  • Reduced oil consumption
  • Lower emissions
  • Lower fuel consumption
  • Increase in detonation margin
  • Better and lower wear
  • Longer Service life



The beauty of the Legion 344ci and 409ci  kit is that it can also be combined with our Gladiator Liquid cooled cylinders for even more performance and weight savings. 



The beauty of the Legion 613ci kits is that can also be combined with our Centurion™ Liquid cooled cylinders for even more performance and weight savings.