I have ran many test over the years...there is even a wrong way to surface tires...I had 2 sets 3 race old tires...ran 10 laps..time..I surfaced 1 set..picked up 2 tenths...another person surfaced other set and only picked up a few hundreths...same with needling tires in spring and fall...good for a tenth on most nights...summer time...you can actually loose time in laps...locks down...these test were done at cerro gordo/ bistate and benhur.and even indoor racing...springfield, duquoin, bmi.....many times within a week of each other....main thing is you have to have a good understanding of how tires will react to the dirt we are racing on...same goes with prep...not everyone can win every night...but , as tire guys we do our best to keep customers up front....I can and will show you proper way to surface a tire that will be fast almost any where nation wide...Deppe is going through this same learning process as you...good luck...and you see me at the track..just come by and ask...or message me on facebook...I told you before I would help you get going...