Weird sqeak/tap noise

[240SX=fun4me!]

Been awhile but I have a new problem, actually 2 of them. I need to know two things, here they are:

1. While letting the car sit and idle down after being irst started, i noticed that at the 1000-1150 RPM range, my engine makes a semi-loud squeaking/tapping sound, and by the previous I mean it sounds like both at the same time. I was wondering if this could be my lifters, or injectors? The engine performs great and has NO oil loss or smoke on start up.

2.The previous owner was a complete moron. He ran the rotors without pads for atleast 1000 miles, judging by gouges and the way he drove it. I was wondering if anyone knew the exact Technicals of how much rotor metal i needed left after cutting, for the rotors to be safe to drive. Im wondering because i am a cheap guy, and naturally I dont want to buy all four rotors just yet.

Thanks. I run a 93 S-13 k24de donno if its ABS or not though.

[Altiman94]

Your most likely gonna need new rotors. They really aren't that expensive, like 20 bux each.

[240SX=fun4me!]

Problem for me is that any parts I actually BUY for this car are gonna be performance upgrade, so when i buy new rotors for it, I am goin something more or less for Prostop or Brembo rotors.

And seeing as how I have 0$ towards upgrades fer now, you can see my predicament.:help

[240SX=fun4me!]

Cutting the rotors would be a lil more cost efficient.

Any ideas about the engine squeak/tap at the 1000-1150 RPM range?