I am looking for input, constructive in nature, so hecklers head for the bathroom and don’t forget the magazine.
I was trying to discern how much load turbo’s add to the cooling system in hard driving situations. Is it the overall enegery (heat) created more by the turbo’s or the engine? The reason is how would a stand-alone cooling system dedicated to the turbo’s. A radiator and pump etc. Most all of you can add just what happens when the turbo’s are asked to go all out. Add some thoughts on your experiences. Thanks

 

horsepower is what is going to determine heat load. a turbo engine making the same hp as a N/A engine will have similair heat loads. if you want to add all the extra plumbing to cool just the turbo it won't lower the total heat load of the engine dramaticly.

 

you also need to keep in mind the rotary rejects more heat than a piston engine, due to the shape of the combustion chamber (surface to volume).

i think if you got a big radiator and ducted it right (big front opening, vented hood) that a roadrace turbo car is doable. you have to keep in mind that the roadrace car is at peak load more than about anything else, so it needs to be able to handle a lot of heat, for a long period of time.

 

Yep. Drag race cars have it easy... they are only making the big heat loads for a few seconds, so the physical thermal mass of the engine can absorb the heat generated, and the radiator has plenty of time to cool the system down when coasting down the coastdown lanes and in the return road. When road racing, you HAVE to be able to reject all of the heat in real time.

Reminds me of those 1500hp BMW 1.5l stock-block motors from F1 20-odd years ago. People like to point at them and say "Look what they were doing in the early 80s - 1000hp/l!" What they often forget is that they dodn't make anywhere NEAR that much power on race day. 1500hp was only for one, MAYBE two qualifyiing laps, then the engines would basically melt down because the thermal loads were so extraordinarily high.

 

yeah the 917's were the same way, for the speed record attempt in 74-75 they went to great lenghts to get the engine to last 2 minutes @1500bhp.

of course its porsche and they are trying to do this with a fan, but thats a whole nother ball of wax