TEC II

[Jason_Leone at amat.com]

<<Dont let all the features blind you , you dont need them.>>

Hmm, and we don't need to spend money building Tomahawk cruise missles, we don't
need them. Wrong.

<<And they dont work with a pulse width resolution of 0,1 millisec and
big injectors.....  >>

Well, since it takes about 1 millisec for an injector to "recover" (which has to
be allowed for in the PW formula), I don't think you have to have the pulse
width that low, for a street car.

<<How its possible to have automatic fuel calibration on the tec system on a
turbo
engine with a narrow band 02 sensor is a mystery to me......>>

Simply using a standard Bosch 4 wire EGO is fine. Standard 0-1v scale. The EGO
correction factor should not be the only control you have over the A/F ratio,
anyway.

<<You have to grind the toothed wheel to get accurate timing.(I had to)>>

I tapped my factory engine speed sensor (uses a 60 tooth crank wheel, like the
TEC II one). had to allow for the timing difference in the software (factory
reads off the 13th tooth, TEC II wants it to read off the 11th tooth). So, my
advance was 12 degrees off from the start (value of "0" in the software). Shoot
it w/ a digital light, plug that value into the "initial advance", and now 0=0.
My Electro crank wheel appeared to be laser cut, and would still work fine. Some
clean-up machine work would definitely help to get really crisp edges on the
teeth. Again, mine isn't even being used...

<<You have to adjust max hp/rpm first! Do you want to run your new engine at
max at the early stages of calibration?>>

You don't HAVE to do anything. You CAN do a few medium power data logging runs,
and then tweak values as you go. Or, you can tune for power on a dyno. I prefer
a load type dyno.

<<You have to turn the engine of each time you want to change calibration.....>>

Yes...and no. You can change parameters at any time, in real time, while driving
or dynoing. To download those changed values into permanent settings, the
ignition must be turned off, and it takes about 10 seconds to flash the PROM. I
feel your pain. It's a flaw.

<<you must let the turbochargers chill of before you take it of.......time
consuming and not userfrendly.The money you save on the system you will
loose fast in more dynotime and headaces.>>

I don't understand what you're trying to say here (grammer). Are you saying that
you have to wait until the turbo cools off, before you can remove the TEC II?
Please explain. As for the dyno money...hey, when getting an aftermarket
ECU/ignition...you should expect to hit the dyno anyway, and pay the fiddler.
Headaches? I don't know of ANY ECU that tunes itself, while you crack beers.
Fact is, you have to know a bit about EFI and your individual engine/car before
you tackle the tuning aspect. That goes for any aftermarket set-up, not just the
TEC II.

<<voltage  compensation dont work, its more sensitive to voltage change at low
rpm than high.>>

I've noticed that the low rpm voltage compensation isn't the greatest. When the
headlights are turned on, or the electric fan kicks in at idle...it stumbles,
and the rpms drop. Needs work here.

<<Acceleration calibration is confusing .>>

Haven't had any problems here.

<<If you want to raise the fuel pressure or put in bigger injectors you have to
start calibrating from the beginning.>>

Not really. You don't have to start from scratch. You keep the same advance
table, and A/F ratio, and just about every other parameter. A few "gamma" tweaks
and a few IOT (injector offset) tweaks, and you're OK. What software are you
using? Were you using the TEC I? I'm using PAF Blend, BTW.

Bottom line:
Any aftermarket ECU will constitute a large portion of your time, to install &
tune. The tuning part is endless, because you always want more power...and let's
face it...it's a pretty good time we all live in when you can screw around with
your engine via a laptop! It serves a purpose, but it takes time, effort, and a
lot of experience. Trial and error, on the dyno, usually gets the best results.
The DFI and the TEC II are great values for what they offer. I went for the TEC
II. The ignition is really good, and it's a single part (unlike the old TEC I).
Be sure to mount the unit away from heat, if possible (it is subject to heat
soak, if mounted to the engine). Heat shields go a long way to avoiding
problems.

The TEC II is good for about 40hp-70hp (over Bosch Motronic)on a turbo VW VR6
application (when tuned properly, and running 15psi+). 400hp at wheels in a daily
driven VW Corrado? It's possible. Enjoy...

Jason
'93 SLC