I read in the s397 forum that for proper sequential shifting you need to have auto clutch on at this point. In the meantime I have an anachronistic solution of using full h-style shifting with my G27 which helps eliminate the snap oversteer. I also advise you set up your differential setting FIRST. Try power at 25-30 depending on your preferences on acceleration and start off with coast at 40-45 and gradually take it down by a few percent until you're confortable. I also read in the forums that weight distribution is your friend. The real cars had jackers for adjusting the balance in car IIRC.
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