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Discussion Starter #1
Does anyone know what the difference in M marking on pulley is between a FI pulley and a factory webered engine?
Also does anyone know the diameter of pulley exactly?
Thanks guys,
Ralph
 

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The outside diameter of the pulley flange is 125.5mm.
For 2L cars the M marks will vary with the year of the car. For 1750's the USA cars were at 34 BTDC and the Euro cars were 38 or 39 BTDC.
 

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Discussion Starter #3
crank pulley difference

I have a 2L circa '84 engine converted to webers by PO, trying get timing exact and wondering where to reconfigure the M marking on pulley for a webered engine.
Thanks for reply ED.
Ralph
 

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I suggest 36 to 38 BTDC
 

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Yes. A weber motor with 9 to 1 or Motronic pistons is likely to run best at 36 to 38 degrees max advance.
 

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Motronics are nominally 10:1 but are really about 9.7. I ran with 38 +/- 2 with Motronics for thousands of miles and my current 10.6 motor will run with 36 degrees. You should be fine with 36-38 on premium gas.
 
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