intake air management (n/a)

[Huw Powell <human@nh.ultranet.com>]

Just some random notes...

1.  A piece of hardware for building "ram" intake setups.  At any Sears
you will find among the various sawdust collection systems the one I
have hanging on my radial arm saw.  This consists of about a 12" square
"funnel" which tapers to about a 2" round opening.  Could be cut to any
inlet size to fit behind the grille, etc., and easily connected to the
airbox.

2.  the "preheater" system.  Examining mine, it would seem that it
generates an air mixture that is quite hot all the time, since the flap
doesn't really close off the preheated air unless its thermostat device
is up over 100 deg. F.  Of course by this time the cool air inlet is
quite open.  I want to examine this closer to see if I don;t actually
understand it properly.  It seems pretty clear, though, that in the
absence of the exh. manifold shroud thing (they must last about 5 years,
I;ve never seen one) and the duct to it, the thermostat will never see
warm air and stay in the rest position - so all the intake air must be
drawn through the "preheater" inlet, which is smaller... 

Advice based on this "theory" would be to remove the thermostat and flap
ASAP if the warm air duct and shroud aren't on the car anymore.  This
would allow the bigger inlet to function.

3.  Inlet locations... on the 82, with the bumpers that aren't "sealed"
to the fender, the inlet is on the side, behind the bumper extension. 
This may actually be a high pressure zone.  On the 85 and later, there
is a cute little yellow submarine periscope sort of scoop inside the
fender, its air comes from around the headlight basically.  The 87 5ks I
saw as I recall had two nice fat plastic tubes leading from the front
area, maybe behind the bumper.

4. I want to set my intake up to be efficient for power when warm but to
still enhance the cold starting of the engine.  I am thinking of
reinstalling the preheater system (shroud is on order), and setting up a
duct to the cool air intake sourced from a cut-down sawdust collector
positioned right behind the headlights or thereabouts, with some sort of
provision for letting excess "moisture" escape before the air filter.

5. Also, can anybody think of a way to set up a venturi device that
would actually create a high pressure zone within the limited space
available behind the right headlights, under the hood?  My head hurts
when I try to think about it...

feel free to comment/correct/ignore!

-- 
Huw Powell

http://www.thebook.com/human-speakers

82 Audi Coupe; 85 Coupe GT
http://www.nh.ultranet.com/~human