Bosch KE-Jetronic conversion to EFI332...possible?

[Scott M.]

Gerard,

My name is Scott Mockry and I am new to this DIY_EFI list,
I also belong to the Audi Quattro Internet list and I have
been doing chip modifications to the Audi OEM Hitachi
computers (Mac-02, Mac-11, and Mac-14 varieties). Orin who
is also on this DIY_EFI list has done the dis-assembly work
on the code inside these OEM Hitachi engine computers. 

Graydon Stuckey who is also on the Quattro list has done a
EFI conversion to the I5 Audi Turbo engines, he can be
reached at the following E-mail Address:
  graydon at apollo.gmi.edu

> From: Gerard <gerard at poboxes.com>
>  I'm interested in getting a better more efficient fuel
system for
> my vehicle. It is a 1990 Audi Turbo (known as the 200 in
the USA).
> It is a 5-cylinder 2.2 litre 3-speed automatic
front-wheel drive
> machine. From the Haynes books I see they indicate the
fuel system
> to be a Bosch KE-Jetronic system. It is still mechanical
and uses
> constant feed injectors. The ignition system is fully
electronic
> and uses a Hitachi unit (with a mass of pins!) to mimick
the workings
> of a real distributor.

Actually you should have a K-Lambda Jetronic system on the
1990 200 Turbo, the KE-Jetronic uses a differential
pressure regulator which was normally used on the Naturally
Aspirated models. K-Lambda has the warm up regulator on the
side of the engine block with two fuel lines running over
to the fuel distributor. The Turbo I5 engines continued to
use the older K-Lambda up to 1990. These later dual knock
sensor engines use the MAC14 Engine Control Unit (ECU). The
ECU actually does have some control over the fuel mixture
using the frequency valve which changes the pressure drop
at the opening slit of the fuel plunger inside the fuel
distributor. 

> I get about 12.5 litres/100km out of this thing in town
driving and
> about 10.5 on the highway (at about 150km/h). I've been
looking at
> rechipping the thing, but all that can be re-chipped is
the ignition
> system since the fuel injection is still mechanical.

The MAC14 ECU also controls the amount of boost using a
Waste Gate solenoid that adds boost pressure to the top of
the waste gate diaphragm. The ECU code can be modified to
increase the boost up to 1.8 bar along with increasing the
overboost fuel pump cutout to 1.95 bar. How much boost does
your stock engine have? In the US we only get 1.4 bar from
the factory. The stock fuel injection system provides
enough fuel under these 1.8 bar conditions. Testing I have
done with a portable exhaust analyzer indicates the fuel
system provides a ~12.6-13.0 to 1 A/F ratio under sustained
full throttle conditions for max power. ~160kW are
available at 1.8 bar. You may want to limit your boost as
the automatic transmissions in those cars are not reported
to be very robust with the higher torque output of ~325Nm
at the 1.8 bar boost pressure.

Hope that helps
Scott M.