Hum, I know that Italian electrics are not the best in the world, but it sounds like you have done a good job on all the ignition electrics so there shouldn't be a problem there, but check it all again, same goes for the fuel injection wiring harness!

The car will backfire if the fuel mixture is too weak as I found out. I had to turn the CO down to pass the emissions test here in the UK and the car does backfire on overrun. I am not sure about your engine but it may have a pre-detonation detector (back of engine under the inlet manifold) which retards the ignition if pre-detonation occurs. If this is not happening and pre-detonation occurs check if the sensor is ok or swap it for a working one and see if it makes a difference. As to the occasional cut out it sounds like an electrics problem, a nightmare I know.

With all the bits you have added I'm not sure what to suggest but here goes.

• 1) Check the ignition timing is correct
• 2) Check that the sensor for timing the injection is in the correct place, the one that picks up the position of the lower pulley on the cam belt end of the engine. If it's in the wrong place or slightly off, the injection timing will be off.
• 3) Check there are no vacuum leaks in the system, especially to the Absolute pressure sensors by the water expansion tank. Make sure all the hoses are tight egg. the vacuum line to the brake servo as well.
• 4) If you set the CO (Carbon Monoxide) to the correct value in the manual (1-2%) the car will be slower than a Corsa going backwards! I have found if you turn it up to about 5-6% things go a bit better (Careful with the screw on the computer as it doesn't turn very far, Don't force it!) Not good for the environment, but this is racing after all!
• 5) Check that the over boost system is working properly as this can cause backfire too.

On our car we have larger than standard injectors I can check the numbers if you like, they are out of the Weber parts bin. Another check you can do is the temperature sensor on the injection harness, you will find as the engine temperature goes up the resistance across the sensor will change. One way to get the mixture richer is make a note of the resistance when the engine is cold. Then warm it up and check the resistance across it again. It should've changed. You can make up parts to fool the injection to think the car is running colder than it is so than it will run rich, variable resistor switch. This will make a difference but will foul the plugs unless you are racing/at high RPM all the time. Finally on the fuel front you can prise the cap of the fuel rail pressure regulator and screw the adjustment in and out to change the pressure.

If you have access to a rolling road that would be great, then you can mess about with all these things and see what difference it makes.

As to the handling I'm not surprised, our car seems to change every day! Not much I can suggest here. You are right I suspect something is still a bit out of line. Tried rebushing the suspension with nylon or 'poly' bushes ????

Find the handling isn't as sharp as it used to be? Feels alittle nervous going around corners. Well depending on the miles (kilometres) you have on the car and the kind of driving you do then the Fergerson diff that balances the torque load between the front and the back could be worn out. It seems that the plates wear and the fluid shears upsetting the torque split. The following firm will rebuild a diff for about 200 pounds sterling. You can't fix them yourself as there are special tools and proceedures required, but here is the address and phone number:

Ricardo Motorsport Engineering

Southam Road,

Radford Semele,

Leamington Spa,

Worwickshire CV31 1FQ

UK

Tel +44 (0)1926 319319

Fax +44 (0)1926 319300

They were very helpful and they turned our diff around in about a week.