Mopar R1 block

Mine is a 4 bolt main at 4.090" currently and will take 4.100", I would sonic test it before boring. Also if you're doing any clean up in the oiling system be careful where the bolt for the oil filter adapter goes in the block. The block is bored for the bolt then bored from the back, the intersection is very thin. Brett Miller told me so but I just had to clean up the intersection a little. The first blip of air to my die grinder found the water port. It probably wasn't .030-.050" thick there. I now have to run a remote filter. I can't say I wasn't warned.

Mine is 434" with Indy heads and intake, solid roller. In my 3350# 69 Dart it's gone 6.40 at almost 109 mph on pump 93.