about 5,000 RPM.
On my 83 z28 305 it is 700 rpm
It could be the Idle Air Control (Idle speed control) valve. Its located on the left side of your TBI and has an electrical connection.
Around 600 to 750 RPM, will vary.
if it has the 350 CI engine it has 250 HP @ 4400 RPM if its the 305 CI engine it has 235 HP @ 4200 RPM
Correct low idle speed should be in the neighborhood of 750-800 rpms. A bit higher when the engine is cold is acceptable. Anything higher, above 1000 rpm probably indicates an issue that needs to be addressed.
The 350 did not come in the 89 RS but here are the specs for all engines in 1989 F-bodies I found this information on thirdgen.org/1989-chevy-camaro 2.8 V6 135HP @ 4900 RPM 160ft/lbs @ 3900 RPM 5.0 TBI V8 170HP @ 4400 RPM 255ft/lbs @ 2400 RPM 5.0 TPI V8 195HP @ 4000 RPM 295ft/lbs @ 2800 RPM 5.0 TPI V8 220HP @ 4400 RPM 290ft/lbs @ 3200 RPM 5.0 TPI V8 230HP @ 4600 RPM 300ft/lbs @ 3200 RPM 5.7 TPI V8 240HP @ 4400 RPM 345ft/lbs @ 3200 RPM 3.8 Turbo V6 250 HP @ 4400 RPM 340 ft/lbs @ 2800 RPM (Turbo TA only)
If it is a fuel injected engine then you can not adjust the idle, it is computer controled. There is no idle adjustment. If it is a carburetor then there is a small screew over by the throttle cable, down towards the bottom of the carburetor.
160 hp @ 4400 rpm
4 BEFORE (ADVANCED) TDC A 800 RPM WITH THE VACUME ADVANCE DISCONNECTED AND PLUGGED.
Any V8 engine, operating at 1,000 RPM, fires 4,000 times in a minute. If operating at 2,000 RPM, it fires 8,000 times in a minute.
it sounds like your idle air control motor is bad. You need to buy a good repair manual so you know how to test it before replacing it