I believe 572Shawn (Member here) has been as low as 9.50's on leafs and truck shocks.
I knew of and saw a leaf sprung RoadRunner up from Connecticut that raced quite a few times on the street and it just barely nipped a bonafide high 9 Buick Stage 2 one night. RR was all lopsided with its traditional SS passenger rear up and had the weirdest shocks, but it took my lunch money and my Boys since we were betting with that Buick.
I know, I know, That's what you get for siding with the dark side, but business is business.
Buick actually was gutted and had boxed A-arms out back and some trick coil springs and that thing would leap frog out of the hole. But on that night, that RR was sitting with him all the way till he just nipped him at the Amen corner.