Ok...Ive only had my Firebird on the road for a few months now and its a 5 speed manual. This is my first stick car....yeah know great car to learn stick on . Anyway...Im just now starting to learn how to get the "R's" up there and shift into the next gear. While getting onto the highway everything is feels good until I get up to 4000 RPM's...it basically feels like the engine shuts down. :::The engine is going faster and faster and faster...gonna hit 5000 reallllllllllyyyyy sooon....boom...crapped out:::: The engine is pretty sound...no major problems (except for the fact that it burns oil like crazy). Before I got the car a used motor was put in....the basics I feel have been done. New plugs wires cap rotor fuel filter ect ect....yeah im sure the plugs are coated with oil but I dont feel that has anything to do with my main problem. My thoughts for my problem are the following...rev limiter kicking in tooooo soon??? timing??? slightly weak ignition coil?? just not enough back pressure??? ( i put a boral cat back system on....smallest restrictor possble...and dual high flow cats). I dont know...Im just taking shots in the dark...Thanks in advance for any info given.

 

Fuel filter, timing, or dirty air filter.

The free flowing exhaust will only improve your upper RPM performance, unless it caused you to run lean. But the only real way that would happen is the fuel filter or the pump. I doubt if it's the pump though otherwise it would act up all over the tach.

Use the tech article to see if any codes are being thrown. It's actually under "FAQ's". It's the second to the last question on this page....... https://www.thirdgen.org/newdesign/faq/thirdgen.shtml