Chevy HEI Distributors

What's the diameter of the 1980-85 (I think) Chevy HEI distributor, the type with the coil on the cap?

What's the diameter of the later Chevy HEI distributor, the type the used a remote coil?

Diameters are of the housing, not the cap.

 

You want a 75/81 Hei as the later ones are computer controlled. As for size most guys think too big and not too big. It's too late to go out in the garage and measure one tonight.

 

DUI says their cap is identical to the GM HEI which "measures 5 1/4" where it attaches to the housing".

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