B4S4 intercooling

[PDQSHIP@aol.com]

Hmmm....  Are you running any S4 mods?  If not, I'm not sure that the gains
on the intercooler are worth the expense yet.....  I would suggest the
Intended Acceleration computer upgrade first, then look at the
intercooler....  All the tests I have done show that the audi IC is pretty
good right from the factory, given the stock limitations of the S4 turbo
itself, that is to say that the turbo creates some heat in its fine execution
of torque, for which it is designed.....  My suggestion is that you do the
computer upgrade first, then the turbo upgrade next, then the intercooler and
exh last......  All intercooler upgrades I've seen to date, may or may not
have been good guesses, and for the price (600-1000) you can do lots of other
upgrades first....  The design that audi uses is pretty good for all but the
most radical mods.....  As for placement, without getting too nerdy again,
lets assume that the stock intercooler is 80% efficient to ambient air temp,
that means that whatever rise in inlet temp at the IC is cooled 80% (lets say
you have 70degrees ambient + 150 charge air, that means you have 220 temp at
the inlet....  you take 20% of the 150 = 30 degrees + 70 = 100 degrees out of
intercooler). What this means is that if you stick that IC infront of the
radiator air flow, you have now put 120 degrees of heat off the intercooler
(and lets assume for argument that you put the intercooler so it blocks 100%
of the available incoming radiator air) that will now make the radiator and
A/C work with a 190degree ambient air temp TO START when in actuality its
only 70 outside (of course you won't be blocking 100% of air flow, so this is
example only)....  So, yes you are going to get some savings, but at the
expense of some radiator efficiency.......  My feeling is that esp on the S4
a OIL cooler is prolly a cheaper and effective way to reduce overall temp,
for more that just the obvious of engine temp....
A IC with a oil cooler on an S4 might be the best bet, cuz even it you block
the radiator, you gain efficiency with the larger oil cooler.....

Let me know if I totally confused you.......


Scott