On Feb 19, 2005, at 20:25, Matthew Yip wrote:
With the changes to the rules for Improved Touring in 2005, the 2.0l
16v is legal in ITA (the class which I currently run) at a weight
around 2400 lbs.
Cool.
The injectors themselves aren't electric, right?
Correct.
If so, how are the injectors fired on CIS-Motronic? Can I control
the injectors to richen the
mixture at high RPMS and so forth?
The injectors are basically just spray nozzles with a spring loaded
valve, which opens (fires) when the
fuel pressure rises to about 3.8 bar. The pressure is controlled
sequentially by the fuel distributor. For
a more detailed description, get a copy of the Bosch Automotive
Handbook, 5th Edition. The only place I know
that carries the book for sure is Autotech Sport Tuning:
http://www.autotech.com
They want $70 bucks for it, so you may try Amazon or one of the other
online book distributors. That book is
a virtual encyclopedia of information on automotive engineering - once
you have one, you'll wonder how you lived
without it. As far as messing with the mixture on a Motronic car, the
straight forward method is by reprogramming
the "chip". The Motronic system is an early attempt at integrated
engine management, and as such it controls
the ignition, in addition to the fuel injection. Several of the VW
tuners offer chips for 9A Motronic cars, but Garrett Lim
of GIAC is the Man when it comes to this application. He was probably
the first person to crack the Motronic code, back
in the days when he had an A1 Scirocco with a 9A motor, which he drag
raced.
There really isn't much you can do hardware wise with the Motronic
system. One thing that could help somewhat is to
have the injectors blueprinted and balanced. I had mine done by Marren
Motorsports, but I installed them when I had
my head and 50mm intake ported and polished, so I can't say
specifically how the injectors effected everything. Also,
VW Motorsports has/had a "Motorsports" fuel distributor, which used to
be available from Eurospec Sport,
http://www.eurospecsport.com/, and was only around $300. Oh, almost
forgot, you can mess with the mixture a little
by changing the DPR current. See the Motronic fuel injection section
in the Bentley.
I'm limited to keeping any electronic modifications "within the
factory computer box" but would love to do something like the Honda
boys are doing and stuff an aftermarket engine management system into
the car (probably Electromotive since I have friends there). Once I
know how the injectors fire, then I'll have a better handle on what I
can do next. In any case, I figure that a balanced and blueprinted
2.0 with a header and legal head work should produce 140 hp at the
crank (up from 134) which is fairly healthy. The next step is to
dump the spare 1.8L 16v that's sitting in the shed and source a
decent 2.0L motor...
You're stuck with the stock cams? If you could even run just the euro
spec cams, you should see
well over 140 hp with a B&B'd bottom end, some mild porting and
polishing on the head, and
a TT race header.
Well, good luck, and keep us posted on your progress!
--Holland
[email protected]
