This M20 E30 325 came in with Stage 3 Modifications, all we had to do is tune it. difficult with a dying TPS

My E30 323 supposedly has a 2.7 low compression
motor in it

Run 3 is actually run 2 after we modified the exhaust with an X-piece for more
torque
Run 2 is the final run done yesterday after my MAF conversion and tuning that
using the Unichip
Now with the M52B28 motor in it:

The graph above a fully modified (Head, zorst, cam, tune)
M20B25 with raised RPM against the stock M52B28 with a tuned header exhaust.
Quite an impressive power difference


Since the ECU was not seeing Full throttle between 1500
and 3500 rpm I had to removed the Oxygen sensors and shorted them out on the
ECU, to tune it properly.
The advantage was going far leaner than Stoiciometric at part throttle.
So far I had gotten 7km/L worst 9.76 best on long road average 8 km/L = 18.8 mpg
over 4000 km’s. So hopefully these consumption figures can be bettered
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The old M20B23 motor gave me 6.88 km/L= 16 mpg at best

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Car.

E 36 3.2L twin Vanos M3

E 46 320 with 2.2L motor

E46 M3 3.2 2002 model
