I've adapted an electronic fuel injection and ignition system to the stock 8ba in my 51 tudor, which now gives me the ability to set the timing to whatever I want at any vacuum level and rpm. I've read on here that timing should increase from 4* BTDC at idle speed to 20-22 at 2000 rpm and above, and that I should have ~8* of vacuum advance at cruise. How much vacuum advance should there be at idle? I had 8* entered in my table which gave an idle advance of 12*, but when I open the throttle and vacuum drops, the advance decreases to 4. Is this what I want or should there timing not depend on load at low rpm (as with a ported vacuum source)? Thanks for any input on this!
The throttle bodies of from a Ducati motorcycle and have 1 330cc/min fuel injector each below the throttle plate, controlled by a MegaSquirt system. The injectors are a little undersized so I'm in the process of upgrading to 500cc units. The ignition is a Ford distributorless (EDIS) system and works great. It runs pretty well but is bogging off idle, which got me thinking about what the timing should be doing at those speeds. Need to tune in the acceleration enrichment as well. Click one of the links below to see more photos.. Ken
51BC364D-8513-49D4-97FD-F12B13EBA294 by
kenhenry_06268, on Flickr