Is that the lean-burn carb that was originally on the engine from inception?
Lean-burn carbs are not set-up for vacuum advance; there is no spark-port on it. It appears that your vacuum advance can is plumbed directly to the manifold vacuum. This will add whatever timing is in the can, to the base timing, unless you disconnect it to set that base idle timing. The thing is, if you did not disable the Vcan to set the base timing, then two things get fubared; as soon as the manifold vacuum drops the Vcan drops out and the timing goes way retarded, and set like this, the transfer slots will be starved for fuel. You will have had to crank the mixture screws waaay rich to keep it running.
But on the off chance that you DID in fact set the base timing with the Vcan defeated, then: whatever you set the Idle-timing to is probably not gonna be enough. But if you set it to the factory TDC to 5* advanced, then set the idle speed, then attached the Vcan hose back up, to manifold vacuum THEN; the idle speed would have jumped up several hundred rpm, as the Vcan advanced the timing. Of course then it follows that you would have reached over and cranked the curb-idle screw out, which promptly dried up the transfers, and in compensation, you richened up the mixture screws. And so you end up with the same sorry state of affairs.
Like I said, the Lean-Burn carb is not set-up for vacuum advance. If you want to keep it, you will have to install a spark-port in the proper place. And I highly recommend that you do. This involves figuring out were to put it, then drilling a hole and slipping in a metal pipe and sealing it, plus you have to mechanically prevent it from falling into the engine. The best way to do this is to borrow a non-LB carb to copy where the factory put it.
Until you get this done, I recommend to; if I'm right about the Vcan getting full manifold vacuum, to not use the Vcan.
But if I'm wrong, and the Vcan is indeed plumbed to a spark-port that I don't know about, lemmee know, and we'll go down that road.
>The other thing you have to do is make sure the fuel bowl is seeing atmospheric pressure, any time the engine is running. There has to be a bowl vent, and the closer to the bowl the better.
Here's some useful chit:
>A sparkport has no vacuum on it at idle, and will not begin to pull vacuum until something like 1500 rpm or higher. The maximum vacuum that will appear there will be close to the same as a simultaneous reading from the intake itself, beginning at perhaps as early as 1800rpm.
>This is unlike a venturi-vacuum port which I don't think can generate that much vacuum, but it starts pulling almost right away.This port if you have one,is always a very small pipe, the smallest pipe on the carb, and it is located well above the butterflies, and usually on the passenger side. It is only used to signal something, usually the carbon canister. It could be the one that I see you have capped there by the choke.. Don't use this for vacuum advance.
Then I have some comments;
> the PCV system needs to have the hose running to the proper port, usually on the front of the carb, and to the underside of the butterflies, where it discharges into the airstream that has fuel already in it. If you bring it in the backside, you will be feeding the rear 2 cylinders extra air.... and they will go lean which is not a good thing, and impossible to properly tune for..
>make sure NOTHING touches the throttle cable nor the KD mechanism. And make sure that KD spring is properly anchored at the rearend of the KD rod and not to anything stationary on the engine, which would tend to pull the throttle open, which would be a bad thing.
>I see you have dual throttle return springs which is a good thing; however, make sure each one is capable by itself, to close the throttle in adequate manner.
>It looks like your top radhose has gone soft and is about to blow.
>Make sure the choke blade hangs vertical after engine warm-up.
>If you still have the charcoal canister, I would make it/keep it, operational. It costs you nothing in terms of performance, and since your engine would be recovering fuel that would otherwise be vented to atmosphere, keeping it could contribute to better fuel economy; besides the carb is calibrated to see it.
>As for the EGR system; a properly functioning system costs you nothing in terms of WOT power, and may or may not affect your fuel economy. It may or may not improve Part Throttle performance. Since yours is gone, and as long as it is legal in Denmark to not run it, I wouldn't go looking for one.
And some questions;
>Firstly, what is that "hose" that runs diagonally across the engine from the driver's side front to the passenger side at the rear, under the throttle cable.
>Secondly; I see a hose-nipple on the intake just in front of the distributor;is that open? What is it's function?
>Third; does your coil output wire run alongside any wires going to the plugs? If yes , this might be bad. It needs to be extracted out and separated at least two inches from all plug wires. When running alongside, it is possible that the hi-voltage in it can induction-fire an adjacent plug.This would be very bad. The wire can cross over any plugwire at or near 90*, no problem, even touching it.
