Rob....I run 48 pitch and use the 92 spur for inside or on smaller tracks and 89 outside or on larger tracks. I almost always run a 23t pinion in mod inside or out and stay close to 7 for the over all ratio. Now in stock I mostly run close to 6.50 for a final. I like the 20t pulley over the 17t pulley as I feel with the 17t it gets up to speed fast but never carries that speed down the straights.
Oh and I checked my Mail.....check yours I have a gear chart for you.