Hi All, The PO fitted the twin Weber 34ICH conversion complete with Empi manifolds. Apart from an air leak, poor mixture and an incorrectly fitted throttle linkage I have noticed that he has retained the original vacuum advance distributor but the Empi manifolds only have a single vacuum connection on one leg of one manifold, close to the cylinder head. From previous experience on an engine with twin 45 DCOE Webers I seem to remember that connecting to one leg like this caused problems with the vacuum advance: It might have been a pulsing issue or simply not enough vacuum to operate the dissy but my memory is not that good and it was about 20 years ago. Whatever the problem was the fix was to drill and tap all four inlet manifold tubes and connect them together on a common rail from which the vacuum was connected to the distributor. My questions to those on the know are: Will this problem be the same on the 1700 Bay engine? If so, should I somehow connect the vacuum from both carbs together? Or should I replace the dissy with a Bosch 009 or perhaps another non-vacuum model? Many thanks, B
Another thought: My 1966 Landrover has the same 34ICH carb. However, it has a vacuum take off point on the carb flange that bolts to the inlet manifold. Could i simply blank off the Empi and then connect the two carb flange take offs with vacuum pipe via a t-piece into the dissy? I can't remember seeing this take off pipe on the two Weber 34ICH on my Bay but it wouldn't surprise me if the PO had left them unconnected and used the the Empi take off. That might also explain the poor running too....
I block one side off and run the vacuum from the one side, have had no issues so far. Running 34ict's and 2 litre type 4
Totally the wrong signal from the manifold. There's a take-off on webers near the base of the carb for distributor vacuum. One will do. Some say needs anti-pulse, some find ok without.
Good questions. I 'think' the Webers were the complete kit from Justkampers and fitted badly by the PO. I have sorted out the throttle linkage and air filter issues (held together with tie wraps would you believe) so next is the advance, balance and to check fuelling. I just wondered how to identify pulsing issues as the engine is not running as good as it should. I am goint to investigate more next weekend.
I'd doubt it's anything to do with the ignition. Ignition & carbs are fairly independant of one another. The vac advance on a mech+vac dissy only covers the case where the mixture's flowing slowly, so needs more advance. Your engine should run fine in most situations without it connected (as with folk who fit a 009). I'd suspect your carbs aren't jetted properly and the whole lot's not been set up right. The vac advance is probably the least of your probs. You do mean ICHs, not ICTs, yes?
yeah tbh the ones supplied by jk are not jetted correctly, i got mine from euro carbs which had correct jets installed. ive never had an issue with pulse either
Hi Tintop... have you kept your original dizzy and, if so, have you kept the points or added an electronic module? Thx
Try and balance them first, at about 2000 rpm. you need an air flow meter and you may be surprised what a difference a small adjustment makes.
