Date: Fri, 19 Oct 2001 08:28:59 -0700
Reply-To: pensioner <al_knoll@PACBELL.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: pensioner <al_knoll@PACBELL.NET>
Subject: Re: prescription drugs, side effects, tach conversions, CARB/BAR
Content-type: text/plain; charset=iso-8859-1
Hi Y'all,
What seems to be missing is a logic description and functional specification
for the ECUs. I'm pretty sure one is out there somewhere and I have some
feelers en-guaged. If I get interesting results from these feeler guages
I'll post. We're doing black box analysis of an unknown system without
knowing the range of possible inputs or how to measure the outputs. Tricky
stuff and fraught with error, that.
FWIW "most" VDO/motometer tach units have as we might expect a different
pulse counting module for different motors. Klaus, jr at PaloAltoSpeedo is
well aware of this and tends to keep the secrets to himself so he can pay
the bills by marketing his skills. They are for the most part
interchangeable. Mosey over to the local picnpull and snap up a trashed
tach to take it apart and see how it assembles. The thingy that has the
flex circuit going to it at the bottom ? of the tach is the "module" to
which I refer. It is my opinion that there are several head units with
various rpm ranges and several modules that drive these head units. The
dial markings are really a conversion between the angular displacement per
revolution and the rpm you want to read at that angular displacement.
Another advantage of SmallCar's guage face kit is that they have a more
modern look to complement the modern motor and they are easier to read than
the white on black original motif.
A possible conversion that retains the look and "feel" of the original VDO
cluster is to use the five cylinder tach from an AUDI 5K. It goes to 7000
redline and works rather well with a modified diode summing junction for
FOUR of the pulses from the six available ignitor signals on the SVX loom.
Yeppo, four not five. Five gives a 20% high reading using Brian's
"undocumented" harness. When trout season closes in the Sierra, I'll devote
a little more investigation into this curious phenomenon and of course post
the findings. Er, the tach thing not the fishing thing.
Maybe there is a side effect here too, that has the result of running the
motor slightly rich. The O2 was very high when I measured the
CO,CO2,NOx,O2,HC on a dyno using the CARB test environment and the proper
GVW parameters. This would indicate rich running with the Cat converting
lots of the HC to H2O and CO2. Sure enough if you idle long enough you get
water exiting the exhaust tip. If there is crosstalk in the wiring harness
that would cause the ECU to operate in "limp home" or "limp dick" mode then
the occasional, cat destroying backfire that Brian mentions would of course
be logical. An side effect of getting to use a state supplied dyno at a
very reasonable rate is that it also has a torque measuring feature. In top
gear at "80%" load and a steady 4300 rpm the rear wheel torque read ~150
lbs-ft. Pretty far from the motor spec of >200lbs-ft. Like the esteemed
Nolan mentions, this motor is seriously underperforming according to the
data so far. Might also account for the high fuel consumption and hot
running. But what is the root cause...conjecture so far...no definitive
data.
The local aircraft folks use a custom ECU of course to avoid all the unused
sensor inputs. In environments where logic prevails over bureaucratic
bullshit one need not have all the "factory original" junk on the motor as
long as the crankcase, fuel system and exhaust emissions meet the specified
bounds. Tacoma is blessed with such an enlightened government as is ootah,
hideho, orygun and other modern societies. Unfortunately, the graft and
corruption crew here in sunny Kalifornia has seen fit to allow any
unregistered alien who can steal a CARB machine to charge 50$ to sniff my
ass and provide a printout that says to the CDFs at DMV that I can pay
another exhorbitant sum to register it.
Seque...The local desert racer folks also use the SVX and other motors in
their awesomely expensive toys. A fine firm in SoCal builds vanagon
automatics to manual shift and reliably (for a race car) handle the 400+ HP
the modified 3.3l motors produce in race trim. They use oil coolers and a
rather large forced air radiator system to handle the heat. Baja 1000 is
coming up. I was astonished at the cost of building a competive machine.
Ready to race, it makes a 12000$ ticket for upgradin' der sing crow pullman
(note required vanagon content here) look paltry. My first house in Los
Altos cost less than a non competitive desert racer costs today. But hey,
you don't have to deal with the bureaucrats to race offroad.
Two methods of verification here in Kalifornia. BAR and CARB. BAR uses the
"referee" a powerful lesser bureaucrat, who extorts a fee to hunker and
grunt over the patient and probe and prod and enemize until he decrees the
worthiness of the conversion. Gives the poor taxpayer a "BAR code" sticker
and after all that garbage you can now go pay the other dude mentioned above
to sniff your ass.
CARB certifies a type of installation and will issue a letter of compliance
that in summary says if you use this and that part specifically on a
particular motor of a particular vintage range you are allowed to have the
previously mentioned dude sniff your ass for 50$ and send the results to DMV
so you can register your car. All this from the state that de-regulates
only the supply side of the power system. Surprised? I'm not. Drop your
pants, sir, and bend over the table or we won't let you drive on the roads
your taxes have already paid for. Truly depressing.
Now where's my welbutrin.
pensioner (SmallCar SVX syncro conversion still under development)
