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<x-charset iso-8859-1>> No I left the hose on last time. Jim mentioned that as well, and I checked > it and I don't think it had vacuum at idle, but I will re-check it to be > sure. > The only stock Type 3 distributors where timing is done with hose(s) on is the twin vac on the dual carb (ie the one yours should have). Whether it makes a difference in every case I don't know, but I can't see why they would bother to get you to remove the hose if it wasn't desirable. BTW which vac connection are you using (as there should be 2 to choose from)? Static timing at about 7.5 deg BTDC is generally a good stand-by timing position; I have assumed that timing with a light at 0 deg (TDC) means the system somehow has about 7.5 deg ignition retard built in, but maybe I'm wrong about that. An extract from an Australian manual states of the dual vac distributor:- "At the initial point of starting the chamber connected to the vacuum source below the closed throttle moves the distributor plate 7° in the direction of distributor rotation, thus retarding the ignition. When the throttle is opened connecting the inner vacuum chamber to the vacuum source above the throttle butterfly, i.e. both chambers subjected to a common vacuum source, the vacuum to the diaphragm unit is progressively equalised returning the distributor plate to the original and static timing point. Further progression of the throttle opening and subsequent increase in engine rpm causes the centrifugal advance mechanism to come into operation. The centrifugal advance assembly operates directly on the distributor shaft cam and independently of the vacuum unit which operates on the distributor plate only. NOTE: The vacuum unit does not advance the ignition timing. It retards the ignition 7° at idle speed and returns the plate to the static position after throttle opening." There's a bit more to the design, as the two ports have different bores, so there is a gradual change to the plate position. It would be worth watching what happens to the advance using a timing light as the throttle is gradually opened. Try timing it on 7.5 deg BTDC and check what the maximum advance ends up at (up to 28 deg is considered fine). Dave. UK VW Type 3 & 4 Club http://www.hallvw.clara.co.uk/ ------ ------------------------------------------------ To unsubscribe, E-mail to: <type3-off@vwtype3.org> For more help, see http://vwtype3.org/list/ </x-charset>