Originally Posted by seaball

you will feel the diffs.

seriously. delrin is a great material for diffs. it's fairly slippery, yet hard and resistant to flow (creep) so it maintains its shape well over time. not to mention, it machines well, and is reasonably priced.

diffs crap out when the balls gall the rings, which has nothing to do with the pulley material. in fact, the schumacher diffs are quite solid, being that there are 12 balls in them (though i'd love to see 18), and the track diameter is larger than most diffs. (the further out the balls are, the more grip they have when drive torque is applied). they also use a bulletproof thrust assembly, that some of the xray guys have found out about.

i believe haynes is still on his original diff builds from february and he's run mod at a handful of events (carpet nats and canadian challenge).

seriously.