I am looking for some advice. I have a 94 4.6 Cougar ,stock except for a Trans-Go shift kit, K&N, and Zex dry kit. The nitrous was working fine. My quarter mile time went from 16.3 to 14.7. I let my friend drive it because he wanted see what the nitrous was like. I am not sure why but when I got the car back I hit the nitrous, it pulled really hard like almost to hard for 75 and I heard some really bad detonation. I let of the gas and the car stalled out and would not restart. By the sound of the detonation I am pretty sure there is internal damage. I am very limited on funds what are my options. I am not very happy with the performance of the 94 4.6 I need more than 205HP . I am considering a new Explorer engine, 99up gt ,96-98 bird or gt engine, 302,351 or any other suggestions or possibly rebuild current motor.Also what is likely broken piston,rings,rods,or head damage.If it is head damage I could do PI heads.