My friend has a 95 4dr accord with a jdm h22a the car wont rev past 6k and vtec hits around 4500 but feels very weak it doesn't pull at all u can jus hear it kick thats about it. No check engine light i believe he is using the p13 ecu also any suggestions.

 

see this thread...
https://honda-tech.com/zerothread?id=830163

Scroll down just a little bit to the section about "Testing the mehcanics of VTEC". The first paragraph seems to be describing his problem exactly.