Nick:
(re: illustration below)
Make sure that the long rod from the front bellcrank (at the pedal assembly) is shortened up and that the rods go all the way into 32 & be certain that there's no slack in that coupler. The bellcrank and rod mounted on the rear of the fan housing are often overlooked. The proper angles of all of the bellcranks are important not only in getting full throttle, but the rate at which the throttles open, so it's worth some frustration in getting everything right. My current 912 works fine with the angle of part 35 rotated just slightly clockwise from the position illustrated.
That said, in the 70's I had an early 912 with the same situation. After hours of messing with it, I ran it up to Glendale (Ca) to these factory trained German Porsche mechanics (they raced a 904 and worked on the best of the 911's.) I didn't even have to finish my description of the problem when one of them just got in, ran it on a lift and cut part #36 between the slot and the arc in it. He then took all slack out and held it in place with some tiny vicegrips. Then he checked for full throttle and brazed it together in its new position. Problem solved, but it wouldn't impress a concourse judge crawling under there.
Hope this helps,
Bill.
