One thing that has me thinking and scratching me head for an answer is my old 500 cubic inch 440source assembly made 275 passes running 8.60’s (440 block build) before it cracked a block. That was back when every track I ran was running 1/4 mile. Now every track I run in “box class” runs 1/8 mile. The only way I can now make a 1/4 mile pass is test n tune nights. I wonder how long that black CJ would have lasted running 1/8 mile only. Hmmmmm. Having a Keith Black block and a mega block I will never find out but I’m still curious.