Cracked Radiator! Damn it!!

[Z-knowphobe]

I love summer...but it's the worst when your car overheats. I drive a 95 300ZX N/A. Yesterday on my drive in to work I noticed steam coming from under the hood. Immediately I look at the temp gauge and of course it's sky high. I pull into a gas station immediately (like about 30 seconds after I noticed the steam). I pop the hood and look at all the hoses....looks fine. I squeeze a few to see if anything leaks....nothing. Under the car is bone dry. I look at the rad cap....looks okay. Then just to the left of the cap where the top ose meets the rad I notice the top plasitc piece of the rad is split wide open, exposing the rad core....which sucks...cause now I need a new rad.

Question 1....are there any good aftermarket STEEL radiators for 90-96 Z's? If so how much and where would I get one?

Question 2.....what would cause the plastic to rupture? My two guesses are that the rad cap didn't release the built up pressure so it busted through the plastic instead...or....something's up with my thermostat. Any ideas? Anyone?