I finally gave my '74 144 a xmas present and got around to getting it tuned (I have only had it 5 months ... lol)

I thought it was running "a little" rich - in fact it was off the scale on the exhaust analyser right across the rev range ! This was using the GK needles in the SUs that the previous owner had put in it.

Had a dig a round in the box of spares that came with the car, and lo & behold there was a pair of KD needles in a plastic envelope :o)

Put them in & took it back for a re-tune ..... just a minor improvement, as the attached plot shows - it's a different car altogether now !

Still "not quite right" at idle, but I think I have a vacuum leak to the manifold from the heater vent control system. I'll block that hose off & see what happens.

Basic specs :
- 1974 B20B, with B20E head
- twin HS6 carbs on standard 1-piece manifold
- D cam
- 2.25" exhaust

For reference, 100km/h in 4th is ~3400-3450rpm.


Dave
Melbourne, Australia