Is there any difference between these two years for the 350? Heads? Block? Crank? Rods? Anything other than the date on them?
IIRC '72 was the transition year and some later engines may have cap screw rods and by '73 all engines should have cap screw rods. o No: In '73 the heads were re-worked so they wouldn't be so prone to cracking, BUT at a cost of less flow potential supposedly. The cranks with the nut and bolt rods had more drilled out of the throws than the cap screw rod cranks because of the extra weight of the cap screw rods. The cap screw crank also has the # 1-2 rod journal partially drilled to help balancing and maybe the 7-8 as well but I can't remember for sure about the 7-8 rod journal? And a few rocker arm assembly differences throughout the years, other than that and some emissions crap they're basically the same. Derek
This was also the time when extra coolant passages were added to the heads and blocks have a scallop to cover the dead end coolant passage. You can use the older style heads on the newer style block but not the other way around. Most 73 engines have the extra coolant passages which eliminated most of the cracking issues the early heads had. Both engines have low compression pistons.
