I've driven both 103 and 104 powered cars and must say the 104 is a lovely engine, if a bit noisy. The 103 can feel like quite a lazy engine but smooth, whereas the 104 has tons of oomph for the big heavy 124.

Just to set the record straight, my 300E was a late '91 car and had the first gear start, ASR and dual airbags.

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1993 320TE M104
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past:

1983 230E W123 M102
1994 E300D S124 OM606 (x2)
1967 250SE W108 M129
1972 280se 3.5 W108 M116
1980 280SE W116 M110
1980 350SE W116 M116
1992 300E W124 M103
1994 E280 W124 M104
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"music and women I cannot but give way to, whatever my business" -Pepys