OK went to the track this morning with itnentions fof launchin at 4000+ rpms for the first time ...running et streets...current best time b4 today was 12.47@114mph witha best 60 foot of 2.0....well with the launching and tires i got down to a 1.56 60 foot and an 11.74@113mph....i was loving life as i had only expected a low 12...so i feel now when i spray my 75 or 100 shot i have a descent shot at a low 11 maybe a 10!!...anywayz my last run decided to launch at 5k and i did it felt great till i got to the end of the track started hearing a banging noise from the rear...ujoints in driveshaft look good...it makes a noise and jerks a little rolling even in nuetral so then i went to put it in reverse and it wouldnt allow me to go...so i knew then i ****ed up the rear....i am currently running moser 28 spline axles with the factory diff but rebuilt and 4.10's im pretty sure its the diff...any suggestions on which diff to use this car is used primarily on the street but at least 2 times a month on the track...so i dont want a full posi for sure