[HWYSTR455]

The guys are all on target with the suggestions etc, would be best if you knew specifics about the engine, like if the piston is below deck (how much), and head CCs.

That, along with your rear gear, and how you anticipate driving the car, will dictate your cam and stall selection.

Do you know the history of the engine, like how fresh it is? Do you know the builder?

Nothing wrong with the HEI, as long as the shaft is good. You can freshen it up if it's of unknown origin, and curve to suit the engine. It's kind of hard to beat the OE HEIs, so unless you prefer a particular distributor, or need a small cap, then I suggest leaving it for now.

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