A few q's from a newbie!!

[Cordsport]

Hi, I've just been givan an S12 and am planning on building it into a cheap track car.

First off does anybody know the weight and weight split of a standard car? I will be stripping mine then putting a cage in but weight of a stocker is a good starting point to order some springs. The front looks like it should be real easy to convert to coilover via some weld on collars, but what do people usually do to the rear?

Mine has an open rear diff, are they all like this? If they are all open can anybody tell me if it is an R200 diff? It does look like one from the outside, and that would make it real easy for me to put a skyline plated unit inside it. (I'm not made of money, just work at a skyline tuners, before anybody asks!!)

That will do for now