He means Ring and Pinion. For auto-x you want a combo if engine/trans/rear axle ratio/ and tire that allows you to spend most of the course in one gear. I have seen some people go faster leaving the car in 2nd even though it does not feel faster to them. So, it depends on the combo really.
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Michael
Plano, TX
1968 Barracuda Notchback
Brian Hobaugh SCCA National Tour June 2014
First Hemi 'Cuda Convertible Ever Built
Short clips: Goodguys Pleasanton autocross and pit videos
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