questions for the supernerds... (Digifiz & nitrous)

[sfwilliams@comcast.net (Scott F. Williams)]

Okay, so I'm going to run a Digifiz instrument cluster and running the
tachometer off the TEC-II is one of the only hurdles to clear at this point.
There is a tach output on the unit itself, so the question is whether or not
the output sends a compatible signal. Here's what I've found out:

TEC-II tach output: sends 12v pulses (or available system voltage >12V)
twice per complete engine revolution.

Question:
Stock 16v ignition box: sends how many pulses per revolution at what
voltage????

And, on a more exciting note, here is my proposal for running a nitrous-only
ignition curve on the TEC-II. I suppose that with some chip tuning, this
would be an easy thing to do on Digifant I (and other VW systems), too.
Please let me know what you think of the following:

Nitrous oxide ignition curve: As we know well, increased air temperatures
increase the likelihood of pre-ignition. Thus, modern engine management
systems will retard the ignition timing when high intake temperatures are
detected. My idea is to simply interrupt that signal from the MAT sensor and
tell the ECU that it is blazing hot outside. This interruption will occur
(when the nitrous system is activated) via a simple on/off switch. Bingo,
I'll have an ignition retard (at a fixed amount that I can input) all across
the timing curve.

What thinketh ye all?
--
Scott F. Williams
NJ Scirocco nut
'99 Subaru Impreza 2.5 RS
Mazda 323 GTX turbo "assaulted" vehicle
Golf GTI 16v "rollycar"
ClubVAC: "Roads found. Drivers wanted."