VW cooling

Phil Burgess · Post by **Phil Burgess** » Tue May 06, 2008 6:29 pm

The one I had on my old mono and the new one are both welded tube assemblies. No reason why you couldn't braze or silver solder it though. They are steel and the total weight including the two short hoses and manifold ends that attach to the heads is 1995g. I had a VW part which is similar but this is a welded steel inlet manifold assembly with a cast aluminium jacket around the centre part, but this was a bit on the heavy side for aircraft use.

SteveB · Post by **SteveB** » Thu May 08, 2008 8:55 am

The original Bernie Pietenpol conversion for the Corvair engine describes an oil heated 'jacket' around the inlet maniford 'Y' where it splits to the individual cylinder heads. The current Corvair engine guru, William Wynne advises against this system, due to the added complexity of the engine oil system and the possibility of debris from inside the fabricated jacket detaching and damaging the engine?
I'm inclined to think that although the air temperature reduction is due to the pressure drop in the carb, the cold air striking the junction of the manifold 'Y' tends to promote a build up of ice at this point? Warming the manifold slightly may help to keep this ice on the move? VW cerainly thought some permanent heat was worthwhile?
I'm going for the air heated method on my Corvair conversion.