Questions and Answers page


Lancia Delta HF integrale (8v, 16v, evo1 and evo2 versions).

Introduction, main characteristics and version differences

Weber-Marelli engine management with almost exact configuration of the Sierra Cosworth system described by Zoltan Almasi: MembersPage/ZoltanAlmasi

16v and evo1 ecus are exactly the same hardware, only firmware changes.

8v ecu functionality differs from 16v/evo1 one in:

1) 16v/evo1 support 2 distinct MAP sensors. A 2,16bar (APS02/03) for lower pressure and a 3bar (APS05/01) for higher one. Aparently this sofistication was there to provide better accuracy while allowing usage in a wide range of absolute pressure.

2) 8v ecu drives low impedance injectors (IW025) in peak hold. 16v/evo1 come with high impedance ones (IW058 same as Maserati Biturbo) but seems to have the same drivers than the 8v, so it could be suitable for low impedance injectors too (practice seems to prove this).

3) 16v ecu has a pin activated for diagnose lamp.

4) 16v ecu has improved firmware with larger maps (injection are 16x16 instead of 16x13, ignition 16x10 instead of 16x8). 16v ecu also has added RAM (2Kb, probably for OBD use).

5) Thanks to better firmware 16v ecu manages the overboost solenoid in modulable duty cicle (at 17Hz), while 8v just triggers the solenoid ON/OFF.

Both ecus (8v and 16v/evo1) share the same pinout except the new services provided with the 16v/evo1 that use pins unused in the 8v configuration (I am refering to ABS communication channel, Diagnose lamp and 2nd sensor).

evo2 ecu is a P8 one like the Escort Cosworth, Fiat Coupe 16vT, Alfa Romeo 155 Q4, and Nuovo Delta HF HPE.

evo2 ecu goes back to a single MAP sensor instalation (PRT06 with 2,5 absolute bar limit).

evo2 ecu uses a Hall Efect sensor for camsync instead of VR.

The enginespeed and TDC sensor: VR with 4 teeth at 90 same as used in the previous generation.

This is supported in firmware 1.1.x

evo2 ecu is closed loop (8v and 16v/evo1 werent), it uses a narrowband lambda.

evo2 are distributorless, they use wasted spark.

Trigger info completed

Engine RPM/TDC crank-sensor: VR type

The crankshaft pulley has 4 identical teeth spaced at precisely 90. The sensor sends a signal to the module whenever a tooth passes a the sensor. From this signal the module determines engine speed (RPM) and once synchronized also the position of each piston (crankshaft position).



Phase sensor (camsync): VR / Hall type depending on model (most are VR with same polarity as the crank sensor)

The stock system takes the ignition sequence from a 2nd sensor situated at the cam (1/2 engine speed).

A phase sensor, located opposite a cam having two teeth separated at 90 (camdegrees) to each other, is fitted inside the distributor. At the passing of a tooth the sensor delivers a signal to the ECU.

The phase wheel teeth are not aligned with TDC, 1st tooth signals cilinder one in combustion aproximately halfway from -10 to 90 and the second tooth (at 90 from the first as previously said) signals combustion in 3rd cilinder (2nd considering the ignition order) so 180 later of crank rotation than the 1st tooth.

Here is the pic of the phase sensor (VR):


The VR signal is similar to the signal supplied by an RPM/TDC sensor fitted at the crankshaft pulley (same polarity).

And here the pic of the phase sensor in Hall effect method (note that the logic of pulses is the same):


Polarity of Hall effect sensor (for the models that use it): +5V with teeth producing a value =< 0,4V. Following this scheme:


The signal from the distributor and the RPM/TDC sensor together enable module to identify the phase of each cylinder during crancking.

The signal patter is the following.

For VR camsync:


For Hall effect camsync:


The camsync is only used during start up, once the engine is started this sensor can be disconnected and the engine wont stop. This camsyn sensor in the evo2 (P8 ecus) is not VR but Hall Effect

Other sensors: CTS (NTC resistor), ATS (NTC resistor), Knock Sensor (audible sensing tuned for 84mm bore with filter focusing in the 12Khz-16Khz (crosschecked with Marelli manual)


Ignition module. There are versions with single module and distributor and wastedspark versions (distributorless). Both use a BKL3B type ignition module to power coil/s.

This is a scheme of the module connections to ecu and coil:


dwell is totally governed by the module and cannot be adjusted. Input voltage is 12V and trigger edge follows this pattern:


The Fuel Injectors

The ECU provides accurate control of the solenoid operated fuel injectors to discharge fuel.

The Idle Speed Control (ISC) Valve

This unit is regulates the engine demand for air depending on the engine temperature, engine load, or swithed on accessories.

The valve, which is controlled by a variable current from the ECU, adjust the air flow into the engine.

The valve is pwm modulated. The stock VAE solenoid is excited at 90Hz (crosschecked).

The Boost Pressure Control Valve

This solenoid valve is directly connected to the high pressure side of the turbocharger by a hose. Depending upon whether the valve is open or closed it will either "vent-off" a portion of the boost to the inlet side of the compressor (valve open) or direct it to the wastegate actuator (valve closed). The overboost solenoid is driven at 17Hz (crosschecked).

The Project

The project is not one :-) but two.

First objective is to build one unit capable to replace the stock ones (8v, 16/evo1 and evo2) just by configuring the camsyc sort of trigger (VR or Hall) and the distributor / wasted spark ignition installation in that car. A sort of plug and play option but with this added functionality: To switch between different maps + the tipycal VEMS functions (programability, datalogging, OBD, display...).

Second objective is to build a racing purpose ecu being it: distributorless with COP, ALS switch, Launch control switch, injection cutoff switch (for sequential gearboxes), different maps switch + the tipycal VEMS functions (programability, datalogging, OBD, display...). Individual cilinder injection and ignition corrections would be interesting. Capability to work in close loop with 4 lambdas, or better, ion sensing would be highly interesting.


My site about integrales and engine management:

Chip Tunning a Rally car:

My Rally Car project: