According to what I know about the axles at all, GM Performance doesn't recommend anything over 3.73's. Which sucks.
Why would you want a spool? Are you planning on only having this thing off-road? A spool would give you great traction in the rear, if you plan on only going straight or if you plan on whipping it through the turns.
Spools do not allow the tires to move at different speeds in turns. They eat tires. Don't do anything to help on the street.
If you plan on keeping it on the road, I would consider a locker (like Detroit) or something similar that doesn't COMPLETELY lock up the diff 100% of the time.
My .0004589 cents after taxes...
J.R. /wwwthreads_images/icons/cool.gif
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