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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
>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: firstname.lastname@example.org *