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Re: I missed dinner last night... :) (long)

do you think he can do something with my A4Qm
At 03:42 PM 8/2/96 -0400, Linus D. Toy wrote:
>or rather, missed eating dinner with my wife.  But no matter how much she
>might have yelled at me (she didn't), you couldn't wipe that silly grin off
>my face last night.  it's still there this morning.  you'll see why in a
>Yesterday afternoon, I got a call from a certain Olympian (as in Olympia, WA
>resident) involved with ECUs.  Yes, Mr. Intended Acceleration.  "Linus, can
>you do me a favor?"   huh?  me?  Given the vast car computer knowledge
>disparity between Ned and me, "I'll try" was about the most I could answer.
>Ned wanted to test some computers from customer cars that reportedly didn't
>work right.  (If any of you want to fess up on your projects, go ahead :)
>They tested fine in his car, but as he put it, his car wasn't an ideal test
>bed.  He was looking for a stock test bed.  In return, I could try out a few
>different computers.  hey--that's a no-brainer, come on over!
>About 7:00pm, Ned and his daughter Marnie showed up with his Pearl 5kcstq.
>"Some" computers was four computers for 20v turbo engines, in various stages
>of programming.  The plan was to see how my car behaved with them.  Sounds
>simple--just find a nice hill where to load the car and drive.  For kicks,
>he also pulled the computer from his car, so we had five computers to try,
>plus my original.
>To start, Ned plugged in his V.A.G. 1551 to check my car's operation.  The
>1551 is the diagnostic computer that interfaces with the car, downloads
>fault codes, and fixes dinner for  you.  Some of you may recall I previously
>reported poor cold engine performance with my car.  Sure enough, when we
>fired it up, it ran rough for the first few minutes.  The 1551 reported no
>faults, but did show fluctuating idle speed and a widely fluctuating O2
>response value.  hmmm bad O2 sensor?  but no faults.  we'll see this again
>later.  So, all plugged in, we headed for a nearby hill.  All tests were for
>drivability, not to test raw power output, so top speed wasn't the
>objective, no times were kept--the goal was seat of the pants feel.  The
>tests were NOT identical in terms of load, speed, road condition, etc.  Part
>of that is operator error--Ned asked that I drive (hmmm...)  Given the
>nature of testing (full throttle up short hills sometimes contending with
>traffic), it was fortunate that Marnie sat in the back seat to watch the
>boost gauge.
>Original computer:  Car warmed up, we started with my computer.  The car ran
>as it always has, with the boost "coming on" with a kick at about 2500 rpm
>(on this hill).  OK, this was our "control."
>Test I:  This box was programmed to IA Stage III levels.  This test was run
>on the same hill near my home (SE 24th for those of you familiar with Mercer
>Island).  This box produced a similar kick to stock, just more of it, with a
>fuller feel.  The pressure transducer on this computer goes to 2.5 kPa
>instead of the stock 2.0.  This causes the dash boost gauge to read low--the
>most I saw on the boost gauge here was about 1.7, but i think that
>translates to about 2.1 or 2.2 bar boost.  Something new that I heard:
>under heavy boost up the hill, a low frequency air "puff" as the computer
>works to control the wastegate more than normal. 
>Test II:  This box was marked "90 Coupe Quattro."  Someone out there has a
>real sleeper.  Marnie used the word "S2" in association with this box.
>There were no customer complaints about this box--see Test III.  I don't
>know the differences between this box and the Stage III box, but it felt
>better.  EXTREMELY SMOOTH power delivery, less of a kick than the Stage III
>box, but stronger, fuller.  This was probably the nicest box I drove--When
>(not if) I modify my computer, this is the one I want.  I didn't observe the
>boost gauge much with this box, but Marnie said it peaked at 1.9--again,
>this is low by 20-25%, maybe more.  
>Test III:  This box was programmed identically to the Test II box.  After
>putting this box in, Ned checked the 1551 again.  Guess what--I've got a bad
>O2 sensor signal.  No big--most of our testing is at WOT anyway <G>  We
>moved our testing over to the Issaquah-Fall City Road for a longer, steeper
>hill, less traffic.  This box and the 90 CQ box were tested by the customer
>and sent back for comparison.  No problems with the 90 CQ box, but this box
>caused jerks and hesitation in 1st and 2nd gears.  No such behaviour in my
>car.  In top gear, at WOT, we did notice a slight anomaly, almost like a
>miss;  nothing constant or regular, just once or twice on I-90--oops, 90mph,
>better back off.  For some reason, this box was not quite as smooth as the
>Test II box--you could feel more "kick".  Ned attributes this to production
>tolerances in the analog devices (resistors, etc) and the pressure
>transducer (which, btw, is hand made). Similar power delivery though.
>Test IV:  This was the last customer box.  It was designed to be used with a
>different exhaust manifold and turbo, which my car obviously doesn't have,
>so we didn't reach its full potential.  The kick was back.  Wow--this thing
>builds boost fast.  I had previously ridden in another '91 200q with
>software similar to this box--the owner lit up the back tire going around a
>corner!  I didn't try that, but this was a noticeably stronger box in the
>mid-range.  Hey--I'm halfway up the hill doing 80!  Didn't get a peak boost
>reading off this one--saw 1.6 and 1.7 easily.  For my daily use, this box
>would probably be OK, but at the track, this one could cau$e problem$.  
>Test V:  Computer from Ned's car.  This is the box that Scott Mockry wrote
>about from our Bremerton event.  This is a whole new ball game...the 2.5 kPa
>transducer is replaced by a 3.0 kPa.  Again, this box needs a different
>manifold and turbo to really shine.  For our limited tests, this shouldn't
>be a problem.  The real problem was--no suprise--the driver--I've never used
>up first or second gears so fast!  I took my foot out of it before long--I
>don't have an R$D budget for my car!
>End result of the testing:  all the computers behaved just fine in my car.
>Problems in the other cars?  One car had had its engine washed, so Ned
>thinks the throttle sensor is shorting out (car would not build boost, but
>computer did fine in my car).  Other computers were from project
>cars--remember the '90 Coupe Q?  Never came with a 20v turbo, at least not
>in the US.  This is a project car of unknown pedigree--the usual caveats
>apply (how hard was the donor car hit, how long did it sit, etc.)
>During the course of the evening, Ned and Marnie had some great stories
>about their recent travels (Europe, East coast), purchases, future projects
>(Marnie's car to get a new engine--someday).  A hilarious story about a
>couple in Seattle who each had 5k turbos--her stock sedan, his modified
>wagon.  He kept the secret for a couple years until one day when she managed
>to borrow the wagon from him--"what did you do to your car?!?"  I got to see
>a few neat tools, including an EPROM burner with about a dozen stickers from
>a competing company on the back.  When Ned modifies (make that, "fixes") a
>previously modifed computer, he keeps the sticker, kinda like tally marks on
>a fighter!  Interestingly, only one company's stickers were there.  Guess
>which one.  Coincidentally, the EPROM burner is an "S4" model--Ned put an
>Audi sticker just above the model label :)
>One last tech item:  those of you with earlier cars (like Ned's) have an
>easy time getting your computer in and out of the car--it simply sits on a
>shelf/tray under the kick panel.  On the '91 200q, the computer is held by
>two nuts on the trailing edge and a spring steel clip on the leading
>edge--that clip is almost impossible to get off--Ned spent a good 5 minutes
>on that clip alone.
>The evening at a close, Ned reassembled my car (bummer--he used my original
>computer), I thanked Ned for the chance to sample his wares, and headed in
>for a late dinner--silly grin and all!
>your faithful reporter--
>* linus toy           email:  linust@interramp.com                   *