Vacuum Advance Source

[msommer001]

Can the vacuum advance for the distributor run into the back on the EGR? This is how it was when I purchased the Bronco, I am hear that, this is not correct. There is another vacuum port on the carburetor that I could connect it to once I confirm that vacuum is only created when I mash the gas.

Correct, I need to make sure that there is no vacuum at idle correct?

I have looked at the vacuum diagrams and they do not match what I have, I will post some photos tonight, but it does not appear that there is a "Cooling PVS"

It would be very helpful if anyone has a 77 diagram they can share. Is the 77 different or should a 76 or 75 diagram be the same?


Thanks in advance.

 

[Viperwolf1]

'75-'77 diagrams should be very similar but probably not exactly the same.

 

[Viperwolf1]

Here is some '77 emissions equipment info. http://library.motoralldata.com/tec...rd_Motor_Company/Light_Trucks_&_Vans/1977.htm

If you have the original decal on the valve cover you can get the calibration code and see what equipment was originally installed.

 

[Bronco Junkie]

When I rebuilt my motor on my '73 I got rid of the vacuum tree at the back of the stock manifold where the vacuum advance for the distributor was hooked up to (if I remember correctly). I now have my Pertronix distributor hooked up to the carb and everything work great.

 

[patterdale]

Correct. No vacuum at idle. If I remember right it is called ported vacuum. If you hook it to the manifold at all it will advance immediately at idle.

 

[msommer001]

I have a connection at the carb that I can connect too. Thanks for the help, I will report on any issues.