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I'm trying to get to the bottom of things with my engines less than expected performance. I've eliminated the valves and Ps & Cs so that leaves only the carbs and the ignition system. I rebuilt the carbs not so long ago so am fairly confident that they are OK. So I'm concentrating effort on the ignition- in particular the dizzy. I know the leads are good and the plugs are fairly new NGKs that look fine. I wrote before that I thought the vac can might be faulty as with it connected, the advance seems to advance too quickly on acceleration- in fact it seems to jump up to about 25 deg advance at about 1500-2000 rpm which doesn't sound right. With the can disconnected the progression is much more even, though the takeoff from idle is far less stable and wants to stall. I removed the dizzy last weekend and took out the advance plate to look at the centrifugal bits. It all looked OK and free but I did notice that the 2 springs that attach to the weights are different. One has a longer loop at one end so that it doesn't contact the weights' post at rest. It looks like it is designed to come into action at higher rpms. So I guess this goes out to Jim as he rebuilds these all the time- does that sound correct? Also Jim you said many times before that you shouldn't notice a difference with the car at rest if the vacuum is connected or not- well I most definately do! I guess that this could be something wrong with the vac take-off on the carbs but I'm pretty sure that it didn't behave like that always, and I've examined the carbs time and time again in comparison to the original carbs and the vac circuit seems identical. The only thing I can think of is that something is leaking and affecting the settings since I removed/replaced the carbs after the rebuild. The throttle response seems a bit sluggish particularly when you take your foot off- its slow to come back down- could that be an indication of something wrong? I'm getting a bit worried about this as at startup it sounds like it could be pinking a bit which won't do my new pistons any good at all :-( Any suggestions much appreciated, Mark Seaton '73 Fasty London ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ List info at http://www.vwtype3.org/list | mailto:gregm@vwtype3.org