Intercoolers..

[Bill Martin]

On Thu, 23 Feb 1995, Craig Pugsley wrote:

> 
> A few questions about intercoolers on turbo engines.
> 
> i/  What is better at removing heat from the intake air:
>     Air-Air or Air-Water?
> iii/If you were to run fuel injection with LPG, would the
>     cooling effect from the LPG expanding as it comes out of
>     the injector be sufficient to not require an intercooler?
> 
>
	Several years ago I looked into an LPG injection scheme, and it
seems that one of the biggest problems is the injectors will "freeze up".
Its not the propane, its the moisture in the air condensing out at the 
tip of the injector. There is quite a big cooling effect from the LPG
phase change to the gaseous state, as the liquid state begins at about 
-40 degrees at atmospheric pressure. The solution is to heat the injector
body with the engine coolant, to stop it from frosting the nozzle shut.
I don't know if you can deliver the neccessary heat with just hot air 
from a turbo outlet, but it certainly would help.
	If you decide to try this, please post the results...I couldn't 
afford to play with it at the time the idea arose!

Bill Martin