GlenL

Should my Euro S have vacuum advance or vacuum retard at idle?

There are two lines to the vacuum can and the one on the retard side has vacuum at idle. The advance side must be on a ported outlet as there's no vacuum at idle.

Is that right? I'd think there'd be vacuum advance when idling.

GlenL

Bump...

Mrmerlin

the vacuum system works like this,
when the throttle is opened then the ignition advances to start the combustion process sooner,
this will make more power, and allow for more complete burning of the mixture.
Also note the burning cycle time is reduced as RPM increases

When the throttle is closed the retard will allow for more complete burning of the mixture since no power is needed, this is done to reduce emissions, it also increases engine operating temperature

GlenL

Thanks, Stan.

Don't you mean "advance" in the second paragraph?

I'm still wondering why the retard line (inside) has vacuum at idle and not the outside (advance) line. Or do I have those functions reversed?

R.Pires

Hi,

Maybe just a little off topic, but why some cars, like mine, have only one vacuum line to the distributor, and other cars with same engine have two lines?
I've never found a value of timing at idle, I don't know if it's not supposed to be a right value, meaning, if you have a difference of 50rpm's at idle it automaticaly changes that value?
Specifically for my MY Euro, what that wonderfull booklet "Models, Dimensions, Tolerances" says is 26º at 3.000rpm with vacuum line disconected.
I'm curious to know if it's possible also to have a certain exact value at idlçe.

Regards