It wasn't too hard of an install, although I DO NOT recommend doing it yourself, I did and I will never do that again. You wouldn't believe how hard it is to lift an 80lb differential while on your back, all the while sliding the jack under it and raising the jack. Besides that only 22 bolts off, then back on. I didn't remove my sway bar, just the mounting points on the bottom of the car, that let it swivel and gave me enough room to work. The hardest bolts were the 12 (6 on each side) bolts holding the axels to the differential, not much room to work.
Overall the install took me about 5 hours by myself with plenty of breaks, I could have done it in 3 with no break, even less if I had known what I was doing. I pulled the old one, swapped covers and installed the J30.
Driving impression: WOWOWOWOW!!! I love it, the rear end feels so much more like it was pushing on corners. On roads with a little loose gravel from place to place where it feels like you will lose control with the open diff, the j30 keeps the rear end planted. Both tires spin. I can now launch ALOT faster, surprisingly faster. Although there is a 4% gearing difference, I don't even feel it, absolutely no difference as far as I am concerned. Although while cruising you notice the tach is a little lower than normal due to the new gearing, better gas mileage I suppose. The gearing aco****s for about a 120 rpm difference at 3000rpm, like I said, not much. Not noticible.
Anyone want to buy an s13 differential with a j30 cover?
