i am very confused about my timming. the manual says for my cam shafts 26/27 it should be 26 degrees with a new chain. the car on the hood says 12 degrees btdc at idle. if it is 26 then is it btdc or after? the manual/cd says nothing about before or after does anyone have some info on this? once again 1990 560sel.

You can't really adjust the timing on your 560 w/o fiddling w/ the R16 resistor.

I strive to get all of mine b/w 11 and 15 BTDC.

From the factory US spec cars come w/ about 2-4 degrees initial.

Jonathan

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jonathan:
with your experience, what timing do you expect with the R16 resistor removed on a 91 560SEL? and how much improvement in gas mileage does one expect below 2500rpm? i understand this resistor affects performance only at 2500rpm and below.

I think you have ignition timing confused with camshaft timing, which are basicly unrelated. The spec on the sticker under the hood is for ignition timing, which is not adjustable except for changing the ignition trim resistor.