I do have a little insight through several friends and parts suppliers to Pauls program at that time, Paul was not against pushing the rules to the fullest extent allowed Start with a unbored 400 block, bore it to 4.375 or 4.380, add a 3.763 stroke crankshaft and legal rods, two ring piston with back cut rings(Ultra lightweight psitons and pins ) a big, stout solid roller cam, a six pak and a lot of hard work and tesing and it will amaze you what that combination will do I remember talking to Paul at Orange county racetrack one Wednesday night at a TNT, he made this comment to me about torque converters (I had ask him what he thought of the B&M O69J nine inch converters, he was in the middle of doing in car testing on the new T/A brand O69J just coming out at that time) His comment was that you had to try a bunch of different converters of the same brand and size to get one good one Once you had that good one you where truly blessed. The differnces between a good one and a so so one was less than .030 and .4 (tenths) MPH Paul had two other customers cars, 1970 and maybe 1971 Cuda's that where running the same combination(440 six pak) so he did get a lot of testing done with three cars with basically unlimited budjets(SP?) His car was always the fastets of the three The Challengers with the T/A fibreglas hoods had a distinct advantage over the Cuda's with the steel shaker hoods, even back then Another thing ou need to know is that Paul had been a Commercial airline pilot as well as being a drag racer in SS/A or SS/AA in a factory backed 1968 Hemi Dart He quit flying once Chrysler offered him a full time ride driving Butch Leals SS 1973 or 1974 360 powered Cuda. He went from there to his own deal on the Challenger, so he always had good support(factory) and was expected to get good results