A friend of mine asked me which set of HE's would transfer heat away from the engine better.

I would think it would be the SS HE's due to the fact there is less mass to retain the heat.

Since I don't know, and it seemed like an interesting question,I thought I would throw up the question to the world.

I don't think there is much difference between NEW steel and ss. The difference comes when the steel ones rust away.

And BTW the HE's don't "tranfer heat away from the engine". Air transfers the heat away from the engine.

he is asking - WICK - away.

i would bet one would wick away hat better than the other??

though the difference may be negligable??

because SS has wider ID than steel 1.7 and 1.8 type - i would assume SS would be better - thought steel 2.0 and SS 2.0 have about the same ID if i remember correctly.

sorry - what was the question

Very little or no difference, unless rusted - which then breaks the air flow from the fan, through the heater boxes/HEs & either vented out the heater flapper boxes (cabin heat off mode) or into the cabin with the heat on - or a combination depending on the setting of the floor lever between bottom/closed & top/open full position.

Of course that assumes the heating system is all hooked-up, complete & operable.

The major cooling on 914s, VWs, etc. is both Air & Oil cooled, so those systems are more important to be in place properly, complete & fully functional - including the engine tins to direct the impeller fans' airflow.

The primary reason to go to the SS HEs is no rust to speak of - at least not in our lifetimes!

IIRC Porsche itself eventually switched to SS on the air/oil-cooled 911/930/993 HEs.