would removing the cat on our cars give us more HP? Also, would cat-back and test pipe for EVOX fit on the 08 lancer?

 

if you remove the cat, you will get a check engine light. Unless you know or have the product to simulate an o2 sensor varying voltage.

 

Removing the cat will probably put the car in LIMP mode (exactly what it sounds like) because of the CEL. As CamShaft said, you'd need a workaround.
Also, you'd probably lose all of your lowend torque. Your car would feel like a snail when taking off from a stop. But it would probably go like a cheetah at high-RPM driving.

Evo parts will not fit. Because of the turbo, their exhaust is very different from the Lancer DE/ES/GTS exhaust.

 

Not only that, but the layout is a bit different. That tunnel that provides a nice passageway for the Lancer exhaust is filled with a drive shaft in the EVO and the exhaust gets pushed aside. You'd need custom brackets, etc.. in addition to the different routing and flange locations for it all to go together. Oh, and you'd need to cut a hole in the bumper cover to account for the extra outlet pipe

That cat removal would allow more flow up top, but could bite into your torque down low.

 

so what about hi-flow cats? i guess putting one on the lancer would be better than going catless right?

 

Yeah, but it's also a HUGE waste of time. If you're putting an HFC on a N/A car, you're basically wasting time and money to gain zero HP. If you're putting an HFC on a turbo car, you're basically replacing an airflow restriction with a different airflow restriction.

HFC is basically a mod where you say "I've done everything else possible, and I want to do something to the catalytic converter, but I want my car to stay legal and environmentally-friendly." It should be the LAST part you purchase.

 

not to mention that Cats tend to be one of the most expensive parts of your exhaust system.

 

Or that it's completely illegal to remove/replace/alter it unless the stock one fails (and even then, you legally have to replace it with a certified unit that meets certain specs).

 

yeah... that too... sometimes I wish I was still living in FL where they don't do inspections for stuff like that...