V8 throttle body

["Randall C. Markarian" <asenna@accessus.net>]

A couple of months ago I bought a "prototype" throttle body from a
fellow lister who had gotten it from an Audi tech who worked at a
proving grounds.  I had no idea how it was different from the stock TB
until today.  

After I had it swapped with the original TB I compared notes I had taken
about the "prototype" TB and here are the differences:

Diameter of each barrel increased ~2mm
No turbulence wedges on butterflies
Progressive butterfly opening 
Dash pot on linkage to prevent idle fluctuation when Accel pedal quickly
lifted

So, what does all of this mean?  Well, the immediate off idle is more
sluggish.  To get better response more throttle is necessary.  Mid
throttle response is not bad.  More noticable power increase over
3500rpm (no surprise there).  Verdict, a keeper!

Friday, I plan to go to the dealership and look at parts fische to
figure out if this is a 4.2 TB or A8-like TB or what.  I bet they won't
have a clue ;)

By the way, if you wondering why I think that it is not a stock part: 
1)  V8 intake systems are covered with a black paint (this one is bare
metal), and 2) there are no Audi part numbers or other ID on it, only a
hand engraved number...hmmm....

Also,  chip info will be forthcoming now that this is installed, and
Friday or Saturday I should have a story about the new subframe bushings
that are going on/already on (looong story).

Later and Happy Thanksgiving!
-- 

Randall C. Markarian

1990 V8 Quattro
1996 Merc E320

Saint Louis, Missouri