[D13]

Had one. Don't bother doing much to it, mild cam, air cleaner, and not much else. As pointed out above the motor is really not a performance piece, it was engineered to be a tow truck for horses. You either have to heavily mod it so it loses its 'original' value, or leave it stock and live with the slug.

Single best thing you can do is replace it with a 502 with a 3500 stall converter. Or at least swap in a 454 Vortec.

Either way your next problem is traction. Slicks and slappers to start, 4 link if you want to race.

I got rid of mine because it was slower than my '72 402 powered Longhorn, and got the same stinkin 9mpg (although the laterones with 4L80E probably get better..). Was getting pounded by stock 302 Fords! And would have taken the 502 and a lot of suspension to fix it.