I am having the Gordini distributor overhauled by David Andrews at Vintage Racing Developments in Sydney. Have a look at the attached data and plot for the test and note that raw data is listed in crank RPM, whereas plot X axis is distributor RPM (crank RPM / 2). Crosses on the plot are the values from my distributor overlayed on the OEM limits. Note that the total advance of my distributor is only 12 (distributor) degrees vs the 13 to 15 factory total advance tolerance and that this discrepancy is of course magnified by a factor of two when considered in terms of crank values, ie. I will have 24 crank degrees total, whereas the prescribed factory limits for total advance are 26 to 30. I expect the total advance shortfall is a legacy of lost motion due to the play in the weight pivots. The distributor was spun to 8000 crank RPM and the advance does not increase beyond the maximum 12 distributor degrees initially seen @ 3250 crank RPM. Information supplied by David Andrews.
So as you can see the 48 year old distributor is not working to its best (The x's should be in the lines) so it will be re-furbished. When re-fitted the engine should run better and a few missing horses should be returned.
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