RustyRatRod said

That's a different grind than the 4 speed cam. The 4 speed cam was a dual pattern, just like the auto cam. It had more duration though and it may have had more lift too.

Yeah, here it is from @krazykuda right out of the 1968 service manual.
68 340 4 speed cam:

276°/284° duration
.444"/.453" lift

Int open: 26° BTDC
Int close: 70° ABDC
Exh open: 78° BBDC
Exh close: 26° ATDC

Overlap: 52°

Per the 68 factory service manual

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junkyardhero said

here's the spec straight from the DC catalog page

P3412044 68 340 Man.-114 276/284 .444/.453" 112

P3690213 Street Hemi GT-112 284 .471/.474" 109

auto 340: 430/444 268/276
manual 340 (68 only): 444/453 276/284

comp *used* to make a very similar cam to the manual 340 unit. i'll root around in my notes to see what i can find.

most all the aftermarket makes a version of the standard 340/360 4bbl cam. i like the melling piece personally.

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