[VintageLambo] RE: Chargecoolers

Laust wrote: One of the major components in the exhaust gas is water, as you can see form the tailpipe, when starting up on a cold humid day, so water injection does no harm to the exhaust or cats, if so equipped. I think you"ll find that this water is due to condensation as the exhaust system and cats/muffs heat up. Not a product of cumbustion, being released as a liquid. As for the thermal efficiency quotient, I think you"re leaving out the difference in cal/g between air and water, with water being many times more efficient than air. Which, not surprising is why modern cars use water cooling rather than air. There"s a pre-war car that used air cooling,,,Maxwell? Essex? Maybach? Oh well. but it diedmerciful death. I was only considering the placement of the intercooler in front of the radiator, not at the middle of the car. I don"t know enough about the chassis layout for a different location. As for the lower limit of the coolant temp: > The vast majority of automotive inter-cooling is done with air to air intercoolers, which is more direct that an air to water to air heat exchange. A coolant liquid intercooler cannot reduce the air temperature below about 180F. I would have to agree with Greg that this is not the case. The lower limit of the thermal exchange would be the OAT minus the transfer efficiency of the cooling system. On a 25C day, it would be possible with a properly sized radiator and chargecooler to get a 15-20C drop without overly restricting the intake charge. I did a bit more searching on the Lotus Esprit, and they are claiming a 30C drop at 9.5psi boost, on a 21C day. They use a competely separate system for the charge cooler. We are, and will always be competing with the engine coolant for air. The smaller radiator fo the liquid system would seem to be more, not less restrictive than an air-to-air type. One other benifit that may not be an issue depending on where the intercooler is mounted is turbo lag. I drive a Saab Aero ocasionally with an intercooler and it"s definitely noticable. Gobs of cool lake water are the key, put skis and a prop on the Jalpa, a pickup tube for cooling and away we go! Doc