Here is what my 95 Z28 just started doing. It pulls like it always has up to just over 5000 RPM and then it pops and sputters it's way to 5800 RPM or so and then shifts. I think my 85 IROC-Z with a TPI acted like this when the MAF sensor went south, but am not sure.

Any advice/experience would be much appreciated.

 

sounds like its either spark or fuel.

try checking the fuel pressure first,thats the easiest.

 

Could be plugs, wires, coil, fuel filter (often overlooked). People will tell you to scan the car and figure out what is going on. Scan for knock retard too, I had up to 10 degrees or so before I installed an LT4KM, now basically none (some knock retard on hard shifts, but I seem to be able to avoid this now). Good luck, there are so many things that can affect high RPM performance.

 

I had the same problem on my car. It turned out to be a corroded coil wire. The wires were only a few months old too. Check the simple stuff first like fuel pressure, cap an rotor, corrosion, etc..... Good luck.

 

i had something close to that diff rpm's if i remember right, anyway i did coil, coilwire, and fuel filter and that fixed it. not sure what one of them fixed it though

 

I am wondering if I got a tankful of bad fuel.....