This is the R3 in my Challenger R3 48 degree,Siamese bore , 4.125 x 4 stroke 426 babbit 2 inch cam ,TTi headers ,Victor heads ,Super EFI intake ,Compstar rods ,Molnar crank ,smith bros pushrods ,Diamond 11:1 pistons ,port injection XFI Sportsman,Hughes Rockers ,Crane Ultra pro solid roller lifters, Cam Tighe cams,Head oiling through rear of heads pushed it to 9,500 RPM couple of times .
Send it in to have the lifter bores sleeved when he set it up in the Rottler mill he said the alignment was perfect & didn't bother apparently the block numbers that end in D were made towards the very end of production had all the refinements included had to take a lot out of the pushrod tunnel for the pushrods also the Victor heads are not drilled for 10 bolt they must be drilled to align with the inner bolt holes not that they are really needed,there is a pic of the Ritter engine run ok but could not get it to hold water pressure some misalignment in the cooling jacket holes have about 4,000 miles on it now
With the 2" babbit bearing cam i had a lot of problems finding a blank tighe Cams in Queensland had a few the had made.