I have a 1990 IROC-Z (350 - 700R4) with a stock computer and a stock chip. I was wondering if there is a rev limiter and if there is a top speed limiter?

I can not give you absolutes. Typically the rev-limiter was set to ~ 9,000 RPM or so. The speed limiter was based on the tires ordered with the vehicle. If factory ordered with Z rated tires the speed limiter was set to 254 mph. Lessor tire'd vehicles were limited to lessor speeds in accordance with the tire rating.

RBob.