Intercooler upgrades..

[Bernie Benz]

Brian,

I'm not clear what you are talking about in your testing.  What is the
reference of your 65F delta?  Temp drop across ot IC, or relative to 40F
ambiant, or relative to a 105F intake, and where is the latter, at the
filter box inlet?

The Audi turbo system was never intended to be a steady state system, but
rather uses the heat sinking ccapacities of the turbo and IC, and relies on
the ECU to dump the boost as intake temp exceeds a maximum.  To quanitify IC
performance and relate it to possible IC upgrades, one must measure the DT
across the IC at a defined mass flow rate, and at given cold side air flow
and temp conditions.  For its size, the 200T IC is a very efficient unit,
beating out most after market stuff, such as Sperco, if normalized for equal
unit volume occupied.

The best bfb is achieved by forcing more cold side air flow, and/or adding
cold side water spray cooling.  For my "3Bing of the 7A" project on the
90Q-20V, I am using two 5K IC cores welded together in a single pass series
configuration (the hot side CSA of the 5KT core is identical to the 200T,
but the 200 is longer by 20 or 30%, I forget exactly).  Doing this for the
low cost and the long configeration best fits the space available.

Bernie

> From: Brian Link <brianl at starsys.com>
> Organization: Starsys Research
> Date: Tue, 19 Mar 2002 17:07:25 -0700
> To: "'200q20v at audifans.com'" <200q20v at audifans.com>
> Subject: Intercooler upgrades..
> 
> 
> Group,
> 
> Does anyone have experience with upgrading the intercooler?  I took some
> rudimentary temp measurements  of the air going into the throttle body.  I
> am seeing a delta of >65F+ degrees.  This is with a oat of 40F, intake air
> temp was around 105F.  I wasn't able to find a steady state temp, I had to
> back off throttle before I could see how high it the temp would go.  I
> could imagine a 85 degree day would result in a 150F to 170F intake temp.
> 
> TIA
> 
> Brian Link