Hey guys, first post here. I have a 92 Camaro RS with the "wonderful" tbi 305 that is having issues getting up to speed. During the fall I replaced the toasted spark plugs with stock Delco's and threw on a set of MSD super conductor wires I had from a previous project. Car ran great. Throttle response and gas mileage went up too. Garaged the car for the winter with 3/4 tank of gas with some Stabil, fired it up every 2 weeksish to keep it going. Seemed to idle fine. Replaced the cap, rotor, and coil with a Hypertech kit and added a low temp fan switch the other day, now the car accelerates worse then my e150 van and has no power. Still idles fine, but has a slight stumble at low rpms that seems to go away as it accelerates. no check engine lights, back firing, or tb popping
I searched too, but being new to tbi I'm not sure what I'm lookin for (other then trying a new coil or cap/rotor). Any thoughts 3rd gen gurus? Thanks much.

 

Try putting the stock coil back on and see how it runs. Make sure you didn't cross any of your wires (spark plug wires) and make sure the coil wires are connected properly.

 

All the usual tests and suspects:

Compression test
Leakdown test
Power balance test
Connect a scan tool to look for codes and anomalies in the data stream.
Fuel pressure check
Manifold vacuum check
Are the brakes dragging?
Transmission shifting properly? A popped sprag in the torque converter will make a doggy vehicle even with a good engine.
Exhaust plugged?

 

This is why I replace one thing at a time on my 91 Firebird TBI. So I know if somethings wrong what it is.

 

After following your tips (thanks again!) and retracing my steps, problem turned out to be sheer stupidity on my part. The new msd coil wire I put on had a boot that was extra long and was not allowing the plug to full snap in (hitting the cap). Little razor blade action fix it in 2 seconds. So the moral of the story is no matter home many tune ups you've done, double check your work.
D'oh!
Thanks again!