Well I performed the J-mod for my 97. I followed the hole directions for the 300-450HP range, updated my 1-2 and 2-3 accumulators, and varied a little when it came to the springs. I went with what some of the Panther guys were doing, and deleted all of the springs. I have firm snappy shifts, great off the line response, and to be honest I was expecting it to be harsher but it isn't bad at all. No neck jerks unless you floor it and then you are asking for trouble anyway. This may be my imagination but I also think my around town MPG has actually improved. I was warned however that if I get a tune I may want to put the recommended springs in there as the extra pressure that the tunes give, plus the spring delte might have me in a neck brace. Overall I have to say that I am pleased and recommend it for people who like to break there tires loose at will.