Swap Meet Score,Heads #3418915 H

The X and J castings are the same. There was no difference except the years they were produced.The first J castings were the 2.02 valves and actually the T/A heads were a J casting with the pushrod holes offset to allow more porting.The later J casting remained the same except they started using the 1.88 valves but the actual casting was unchanged. They would crack between the seats but you have to realize that a lot of these heads were 25 to 30 years old before they started cracking.I believe the advent of unleaded fuel only and lower octane values is what eventually led to the heads cracking. I had literally hundreds of small blocks back in the day and I dont remember any heads with cracks until the 1990's.