Better performance and fuel economy

About the Benefits
  • Overview
  • Getting rid of the heat
  • Heat - the top end killer
  • More power per cubic inch
  • Better performance and fuel economy
  • Radiator technology - past and present
  • Shock cooling - Problem solved!
  • The secret to achieving longer TBOs
  • Flying faster on the same power - reducing cooling drag
  • Side benefits - Safer cabin heat
  • Dispelling the Myths

  • Takeoff check: Mixture set to full rich
  • As most pilots know when taking off from lower altitude airports - usually at or below 3000' MSL our handbooks tell us to set the fuel mixture to full rich. Every wonder why? Well, in order to keep our engines from serious detonation our fuel delivery systems are calibrated to provide a super rich mixture when we set the mixture control to full rich. Those of us with fuel delivery instrumentation can watch a typical O-360 engine guzzle upwards of 18 gallons of fuel per hour in the full rich position with the throttle wide open.

    We are using substantial amounts of fuel to cool our engines during periods of high power settings at low altitude and we are not only getting nothing back for this (other than keeping our engines from blowing up) but we are also losing power! Yes, a super rich mixture causes a considerable amount of power loss. Why? Quite simply because we are cooling and absorbing a significant amount of the heat produced by combustion. There is less heat available to be converted into mechanical force.

    Now what if you could pickup an extra 5 to 7 HP on a typical O-360, 180HP engine during takeoff and use as little as 12 GPH during takeoff and high power operations below 3000' MSL? Well you can as soon as you convert your air-cooled O-360 or O-540 to water cooling.

  • Peak lean EGT or 50F lean of peak EGT at all times
  • Yes, it is possible. Imagine that you set your mixture to peak lean EGT on takeoff and keep it set to peak lean EGT at all times. Instead of burning upwards of 18 GPH at sea level you are now burning 12 GPH or less and making more power! Our dynamometer testing has shown that a liquid cooled, 180HP, O-360 engine will produce 187HP at peak lean EGT at sea level using about 12GPH without any sign of detonation. In fact we tried everything we could to make the engine detonate and we couldn't! We even lugged the engine down to 1600 RPM at wide open throttle (28 in/Hg manifold pressure) at peak lean EGT and left it there for 30 minutes. It was quite happily producing 355 ft/lbs of torque at 1600 rpm (108HP) as smoothly as it produced 365 ft/lbs of torque at 2700 rpm (187HP). At full rich the same engine fell to about 180HP at 2700 rpm and guzzled fuel at the rate of around 18GPH.

  • So you can have your cake and eat it too
  • Lets see - more power on less fuel - that's hard to believe - but its true! Water cooling so significantly reduces the temperatures of the combustion chamber that the engine can safely be run at full power at peak EGT, 50F to the lean side of peak EGT or even leaner! During our dyno runs we regularly brought the mixture back to such lean levels that the engine would barely run and yet we never had any detonation. Peak EGT and 50F lean of peak EGT mixture settings are not recommended for the air-cooled O-360 engines and with good reason. There is the high probability that detonation will occur and the distinct possibility of engine failure as a result of detonation.

    1600 RPM at wide open throttle (28 in/Hg manifold pressure) at peak lean EGT! I'd never do that to my engine! Yes we know - that's because quite simply your air-cooled engine would self destruct if you did that. We did it to prove a point. That even the most mismanaged water cooled engine would still continue to operate safely and reliably. Now we are not suggesting that all water cooled engines would behave this well - we have only proven this on a typical O-360 engine. However, we believe that we will achieve similar results with other engines as our test program continues.

    Liquid Cooled Air Power © 2001 Liquid Cooled Air Power. All Rights Reserved.
    1413 Prospect Ave., Hermosa Beach, CA 90254
    Proudly MADE in the U.S.A.
    Proudly MADE in the U.S.A.