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Yes, I started to dismantle the dizzy weights/springs and planned to both weld and change bushings on both your and @lars recommendations.
But it seems as previous owner already been there with a weld. If I limit it even more it will be more or less stiff 😏
Added pic below on current setup.
Thanks!
The brass/bronze advance limiter bushing, as shown in the photo, should be replaced with a plastic one as this will cause the advance plate to bounce around.
Both the mechanical advance and the vacunm advance movements can be welded and ground back to achieve the amount of movement you need. Minus a welder, I would try JB weld to do the job.
to grind it back use a dremal or small rat tail file.
having a higher duration cam requires some tweaking to the stock timing set up to get it to both idle and run well.
next up Is the carburetor. That may need some tweaking as well.
Can use roll pins to limit mechanical advance. Just drill the holes and press them in, no welder req’d. I used a screw to limit vacuum advance so I could have adjustability, I did this by welding a nut on. But you could easily clamp a small piece of flat steel to it, and keep moving it until you get the amount of travel you want and then epoxy it into place for final fit.
For me, 3/32 roll pin was just right. I have 20* initial, 36* total mechanical advance. I currently have my vacuum advance limited to 11*, for an all in total of 47*. But I’m not finished dialing that in, I may allow vacuum to advance a few degrees more. Thank you Lars and Le Mans Master and everyone who posted information on this thread. This thread was the key to getting my mystery engine tuned and timed correctly. Appreciate you guys!
Last edited by LinearAccelerator; Oct 12, 2025 at 10:14 PM.
