Type 2 - Rev Limiter - [16 bit - complex function]

Systems using the 8052 Microcontroller and the new 60/2 timing wheel. This became standard on new Motronic designs in the late 1980/s.

The method of calculating rev limit has changed. It is now based on CPU clock speed and Microcontroller timer speed. Two consecutive bytes are used to calculate rev limit.

Example: Rev Limits 0261203070_1267357459_Porsche_968_M2.10

Rev Limit Formula = Conversion Factor / ( Byte1 X 2^Byte2 )

Example: Rev Limit = 8C03h
Byte1 = 8Ch
Byte2 = 03h

Rev Limit = 7,500,000 / (8Ch X 2^03h)
                    = 7,500,000 / (140 X 2⁰³)             [ Where 8C hex is equal to 140 decimal]
                    = 7,500,000 / (140 X 8)
                    = 6696.4 rpm

Shortcut.....

Rev Limit = 937500 / Byte1                   [Using Conversion Factor/8 from the table saves time]
                    = 937500 / 140
                    = 6696.4 rpm

Where Used	Factor	Factor/8

Alfa ML4.1	12500000	1562500
BMW 325i Porsche 968 VW Polo 6N	7500000	937500
Alfa ML4.1 Porsche 944S Porsche 944S2 Porsche 964 Opel 185 BMW M3 075	12500000	1562500
Opel 3017	7288400	911050
Audi RS2	7868800	983600
BMW 318i BMW328i M1.3 Fiat Punto GT	7300000	912500
VW_Golf_Jetta_M2.9	7092800 ? Approximate Value	886600 ?

There is no cosmic significance in the names "Type 1", "Type 2" and "Type 3". I had to call them something...

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