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Dave at Pelican Parts Dave at Pelican Parts is offline
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Join Date: Dec 1969
Location: Silly-Con Valley
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I would put the vacc line on the retard side, myself. If the vaccuum port is truly below the level of the throttle plate, it is for vacc retard.

In the stock FI throttle body, the advance port is just *at* where the throttle plate sits, or just above it. When the throttle is open a very little, the air going through that small opening (and right past the vacc fitting opening) creates a venturi effect which creates a very low pressure. That is used to work the vacc advance at part-throttle.

If you have a vacc gauge, you can see how much vaccuum is on the port under what circumstances. If it is high at idle and gets less as you open the throttle, that would be appropriate for vacc retard. If it is low at closed throttle and gets high at part throttle (and goes down again with more throttle) then it would be appropriate for the advance.

You may need to mess with the timing quite a bit to get it to behave the way you want.

Good luck!

Old 12-07-1999, 09:24 PM
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