Usually came with 340 smog and 360 motors. Any pluses with this head? Thought that MP liked this head and it flowed better than the J.

I think the smog 508 head was the hot setup in NHRA stock, not the one your asking about

I believe that was the 308 head...

Howard
Mrsmallblock

The 974 head has the large intake ports & small intake valve.

I have only ever had two, but they did have 360 cast in the top of the valley area & Js cast underneath.

They should not be confused with the earlier 915 castings with J, O, U or Z letters.

1974 - 1976. Nothing particularly special about 974 heads compared to the others. But not OEM on 340's.

Moparts tech pages

308 were used in the final years of LA 360's and were similar to the over-the-counter 576. People have different preferences for different reasons.