The launch in the video above looks pretty darn good. Not sure where you get the 165% antisquat number... If you are watching "Kevins youtube videos on antisquat", they are only good for one thing...entertainment. I watched your video multiple times in slomo and it isnt hitting the tire extremely hard. Alot of variability comes in track temp/track prep, as well as the age of your tires. Replace the front springs as mentioned and put a good dbl adj front shock on it. IMO, you'll find as much hook controlling the front as messing with a stock 4 bar rear setup. Some people will say pinion angle doesnt matter..... however, very few have stated what they have.
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