I have and 81 Kawasaki 750ltd, the acceleration goes crazy and red lines the rpms, usually during or right after a shift. The rpms go way up and stay there even after releasing the throttle. It gets hard to control at times, not a constant thing just every now and then

have the fault codes read and use a quality injector cleaner in the fuel
it could be low fuel pressure , injector problems or accelerator position sensor related

Not driving a corvette? Just kidding. More details are important. How slow is your acceleration? Is it 0-60 in 8 seconds, or 20 seconds? What is redline on your car? If redline is 5K then 4000 is a good responsible shift point. If redline is 8K then shifting at 4000 is probably robbing your engine of it's torque and horsepower band. I believe the GTS model has an 8K RPM redline, the GT may be lower, but in that case, shifting at 4K is too soon for strong acceleration. Your Tachometer should have redline clearly marked. For responsible use, stay below that, maybe 10-20%. For economy stay further still, but for power you need to let the engine use it's RPMS, especially smaller and fewer cylinder engines usually don't make their power until they are half way through the RPM range and above.

Your car acts like it needs a transmission service.That's where you should start. GM cars can act like the trans is shot when all it needs is a new filter. I don't understand how the dealer could miss it, though. Get back to me and let me know.

Check the transmission fluid.make sure the car is at operating temperature and in park.go to parts store and buy transmission filter kit. automatic transmission works on fluid pressure if it is restricted the tramsmission won't shift right.the fluid and filter are to b changed usually between 40 to 50k miles

it sound like it could be a vacuum problem. I have experienced this on cars i have worked on it usually turns out to be a vacuum problem 90 percent of the time.

Maybe the torque converter is not locking up right. Or the clutches in transmission are worn, or the transmission is not shifting up to higher gears.

Check the trans. fluid to see if it's on the full mark.

when was the last tune up done ?

Sounds like you have a bad plug wire, I would start by replacing plugs and wires (needs to be done every 60k) and go from there.

With normal acceleration the 1st to second shift point should be around 2500-3000 rpm. Most of your shifts under moderate acceleration will take place at this same point or when there a light load on the transmission. Under hard acceleration the RPMs will climp higher due to increased power needs and the computer will shift when less power is needed or the RPMs climb to an unsafe speed say5000-6000rpms (depending on where yours redlines). Also going up a steep hill will raise the RPMs higher and goind down a hill will cause a faster shift at lower RPMs. These can always be altered by an individual owner by adjusting shift points, using performance parts and if you have problems (low tranny fluid/trans issues). Your trans RPMS are fine and will vary depening on how your foot accelerates. The shift pattern should be the same every time you drive slow/medium/fast/, look for changes in those patterns you will also catch a problem early.