Quote Originally Posted by Hot Rod Surfer View Post
Dont want to hijack this thread, but I have the same question, same engine, perhaps the same use.

I currently have an old edelbrock 1406 on a edel high perf intake manifold. Neither myself or another old school mechanic can get it tuned just right.

So I have been looking at alternatives, get another rebuilt 1406, try to rebuild it myself, or look at a holley.

On other forums I have seen folks say that a vacuum secondary is the best thing since sliced bread. I dont believe that the 1406 has a vacuum secondary but the holley O-80570 does.

The question is Are vacuum secondarys better in a street/mild performance engine better?

Thanks!
First of all, E-brocks have a mechanical secondary with an air opened valve, for no better term above those secondary plates.

Secondly, most problems with these carbs is dirt - they are quite sensitive to crud. You need a very good filter ahead of them. This is what I use: and it's the Speedway 6" version



An early photo with only one bracket installed

Then, they are very easy to tune but you will need one of their kits. An 'old school' mechanic may have the skills, but he just can't get these carbs running their best without that kit as well as the Owner's Manual: http://www.edelbrock.com/automotive_...ers_manual.pdf

The kits - and this one is the most complete: http://www.summitracing.com/parts/EDL-1479/ (or the EDL-1487 which is for fewer parts and choices and quite a bit cheaper)