Problems with my MR2...please help

[MR2spyder88]

I put on a custom exhaust, It is a flowmaster muffler with a dual 2.5 inch outlet. After i did that i noticed a lag in the throttle when i punched it, almost like the engine was being choked. Well i figured that since i put on an exhaust i should put on a performance intake and that would solve the problem. Well when did that, the lag is still there, and i lost all of my top end of my car. I couldn't get the car to go above 90mph. Ive been told a couple things like theres not enough back pressure to the engine, or the engine isn't getting enough fuel to compensate for the air intake, and ive also been told that the computer is messed up because of the modifications and it needs reprogramed. I dont' know if i need a chip of what. I really can't afford much but i need to do somthing. If anyone has any cheap suggestions please let me know.

[MR2spyder88]

It is an 2001 MR2 spyder

[andyb16]

Try spyderchat.com (I think...). This is more or less mostly MKI and MKII guys on this site.

[MKI_S/C]

need more back pressure find a way to put a silencer in the pipe

[todd0305]

Yeap Back pressure. I noticed that too when I gutted the first cat and removed the second cat.