Anyone know why in the period of 1976-1980, the R107 450SL could be found with either a cast iron or aluminum alloy fuel distributor?


I'm helping a buddy out in getting a replacement. His car had an engine swap many years ago and that engine had a cast iron unit. However, there seems to be a choice of the two fuel distributor units. Why?

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03 CLK430 Cabrio 211K Pweter Silver/ Oyster Leather
90 300SEL 214k Pearl Black/ Alto Grey/Black Leather

Prior: 85 190E, 88 300TE, 89 300TE, 90 300E 2.6, 90 300TE, 92 300E 2.6, 91 and 93 300SL, 87 Ferrari Mondial Cabrio