what does it mean when the cars cold idle sits at 1200rpm cold, and 750 when it has been running for an hour or so both under 100 degrees on the thermo? is there anything wrong, car is a 1989 Iroc it has 36.7 K on the clock and is pristine. It has the L98 cam would that raise idle?

 

The ECM table for idle speed VS temp shows 32-44°C (90-111°F) to be 900-750rpm respectively. How the ECM attains, and maintains the idle rpm involves the IAC, and a bunch of other stuff.
The problem here is that the engine isn't reaching normal operating tempearute which should be around 190-220°F.

What have you modified to keep the temp below 100°F?

 

not much, their are no longer any vacuum leaks, synthetic engine oil, replaced some gaskets and did the ignition, but though when she sits for about an hour or two without moving she will hit 220, but I never go over maybe 150 even when in extremely hot weather, normally I can drive for two hours without poping 100 degrees, I have redone the ignition but before that it still never went below 750 rpm. When I did the spark plugs my idle went up another 200 rpm, Bosch 4's. Car has 36,700 miles. It has seen 7000 rpm in short bursts but never anything that would change temp, though at one of those high revs the engine blew out the interior of the cats and muffler. It tached out past 7000 on a surge and I had bring my engine back up to that level to correct the tachometer it stuck at past 7000. She is considerably faster than most other Camaros in the area, i am basing that against a 87 TPI auto with a cam and a exhaust, and most of the ***** cars. With the stock exhaust, it is fairly loud and my car shakes very hard when it hits 750 rpm. i gotta go