Quote:
Originally Posted by Gunter
Quote by wwest:
"This is nothing less than PURE BS" 
Why divert engine cooling airflow in favor of cooling the exhaust manifold rather that having FULL engine cooling airflow AND cooling the heat exchangers in the same process...?
Grady never said to just cool the exhaust manifold without full airflow for the engine. 
You can't have FULL airflow through the engine's cylinder cooling vanes while diverting a portion of the airflow to "cool" the heat exchangers, exhaust manifold.
Plus...It seems to me that the extra cylinder cooling you get by using ALL of the airflow might result in the exhaust manifold being just as cool as otherwise, diverting a portion of the airflow to directly cool the exhaust.
Consider more carefully before calling the input from a very experienced and helpful contributor pure BS.
It goes without saying that the cylinders need aircooling before anything else and the design by Porsche was always to have full airflow for the engine.
Exactly...!!
Just another way, quite FACTUAL way, of calling Grady's input BS.
The auxiliary blower is not absolutely necessary but was added to supply extra heat for the cabin at idle, AFAIK. Main airflow has always come from the big fan supplying aircooling whether the flappers are open or closed.
So, whether using the air for the cabin or just have it diverted into the void, the design calls for full airflow through the HE's either way and I'm sure Grady knows that.
If the extra blower is removed, a block-off plate is used and a hose is re-routed to ensure that full airflow is maintained as intended by design.
When adding SSI's, the auxiliary fan and hoses on top of the engine are removed and different plates left and right of the fan are installed with short new hoses to the SSI HE's.
That's "back-dating" and actually gives more heat as experienced by this old ME.  |
"...The auxillary blower is not absolutely necessary.."
Yes, I suppose in the alternative one could always push in the clutch and use the gas pedal to elevate the cabin heating airflow enough to be comfortable on a COLD day/night when the engine might otherwise be at idle. My experience was that the auxillary blower required a modification in order to keep a reasonable cabin comfort level on a cold day, "Seattle" cold day.
Oops, correction..
The blower/fan modification resulted from not being able to keep the interior surface of the windshield defogged consistently.