X J or TA Heads

It's wrong. If it said Rosie O'donnell was the sexiest woman in the world, would you believe it because someone took the time to publish it? Just like the A body rear length in some of those is wrong. Look at the rotten exhaust manifold casting number list that has been floating around for 20+ years.

894 X heads were to be stopped on 340's at the end of the 69 model year with remaining inventory to be used during 70 model year. 915 J's were the primary head on 70+ 340 until the 587 was used in 1973. I have and had a couple of engines/cars that were 70 models with 894 X heads, but, the vast majority of 70 model year and EVERY 1971 340 had 915 J heads on them. We had a new 70 Swinger 340 and my neighbors had a 70 Duster 340, the Duster had X heads (picked up first week they were in dealerships), the Dart (Early December built) had an X and a J on it... Go figure

You ever seen an unmolested all original 1971 car with 894's from the factory? Nope, not going to happen!

Why do you think people ask if 915 J head for sale have 2.02 or 1.88 valves? Because they were used on 70-71 engines in 2.02 form and 1.88 on the 1972 model year engines.

This is a case where the service number/manual didn't change numbers when the replacement casting/part did change. It happened quite a bit when a part was superseded.

Believe what you want, those manuals have some bad info regarding part numbers and dimensions.