I have been posting questions for several months trying to get to the source of my idle problems on the B20 where it would idle OK when started but change to a very high idle after driving at 50 to 60 MPH. This was accompanied by poor gas mileage and constantly fouled plugs.

I got rid of the one piece intake/exhaust manifold and installed an auuminum intake and found a dual pipe exhaust manifold locally. Using the cut washer technique recommended by Phil S. to accomodate the different thickness flanges on the two manifolds, they went on just fine.

Somewhere along the way, the distributor became the topic and I became sold on the merits of a vacuum advance distributor. It was a little difficult to find one of these but the guy who rebuilt my carbs has a contact in Sweden where they are more common so after a rebuild, one found it's way to me.

With these two changes along with a proper PCV system, the car starts and runs absolutely great and a little thing like the idle returning to where it is suppose to be will never be taken for granted again.
A lot of you have offered suggestions and instructions along the way and for all the help I am eternally grateful
Dennis