altezzaclub Posted May 7, 2020 Report Share Posted May 7, 2020 Oh I see! That is a lot in that case. Do you crank it with the accelerator open, or crank it with your foot off? I see people start a car with their foot off the pedal, which gives it max vacuum advance, although I start a car with maybe 20% gas so at cranking speed there is virtually no vacuum & no vacuum advance. I did a lot of work with vacuum advance and springs when I fitted an electronic dizzy, they are hopeless for advance as they're made for 5K forklifts. Eventually I found the right springs to give low advance at idle and a fast curve up to 35deg at 3000rpm. I marked the pulley with 'liquid paper' or some similar typing correction liquid so I could measure out to 50deg. Your manifold vac gives max advance at idle & over-run, and a large advance at cruise, and no advance under acceleration. Other carb manufacturers use a port advance which gives no advance at idle and max at high rpm, so there are options out there. The vacuum advance is for pollution control, to get a better burn and cut nitrous oxide emissions in lean conditions, you can disconnect it and just run on the weights in the dizzy. That's worth a try, plug the hose with a nail and set the timing to 10deg at idle, and see how it drives. It will be cranking against only that 10deg then, a much easier job. Most of the dizzy work is here- Quote Link to comment Share on other sites More sharing options...
Viterbo Posted May 10, 2020 Author Report Share Posted May 10, 2020 So it seems disconnecting the vacuum advance helped a lot. Today I went to the gas station I mentioned and the car started with no issues there. Didn't notice any loss in performance by running it with no vac advance. I also charged the battery for about 4h before going which might have helped Quote Link to comment Share on other sites More sharing options...
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