I just bought a 1989 camaro RS v8 from some guy for 400.00 and every morning I start it up it knocks for about 25 seconds? What cold this be? The car doesn't leak oil. Please let me know if you need further info?

 

Is it valvetrain noise or actual lower end knock?

Also, how is the oil pressure.

 

The knock started when the previous owner started it up and the next day I drove it. It knocked when I started it and the went away in a few mins. Now going on the 5 day it doesn't know anymore but it's been very hot (102) here and now when I got off work and went to the car and started it up it idles high like a cold car would, when sitting for 10 hours. I put it into gear when it was idleing high and when I drove off I noticed the temp was getting hot.. I drove fore about 5 mins and parked at my cousins house to let the car cool down. Made it home and now I don't know what to do or check besides water lol

 

What kind of knock ? Ignition knock ?
Some of the things you say lead me to want to check the ignition timing.