I'm seriously considering adding high flow cats to my 2011 RT. Please advise me.
Will they throw codes? Will the car pass inspection? Will they give me low end gains? Better throttle response?
I have seen about 20 hp from high flows. First they are NOT street legal, and they don't pass emissions.
That said, some companies like soho have figured out how to get around codes, and the states which use the computer to test emissions. Some states don't actually measure the exhaust, they just plug into the computer and ask it, is the cat ok? and if the computer says yes, you pass. The way to get buy with a non street legal car is rear o2 extensions. With the extensions the sensor isn't getting all the data and it "lies" to the computer making it think the stock cats are in place and no codes, and emissions are passed despite the fact the actual gas exiting the tail pipe is exceeding the legal limit.
A car with cat back, or cai is ok with either the stock tune or DiabloSport tunes. If you install headers, high flows, cat delete, camshaft, turbo, supercharger, bore / stroke, any of these or any combination of them require custom dyno tuning.
For example an r/t with shorty headers requires 3-5% fuel. and they produce about 9-10 hp. High flow cats release about double that so, its really going to be lean, and you need a custom tune to be safe, and realize all the hp they offer.
07 3.5L Charger K&N CAI, Magnaflow Cat back, JBA shorty's, DS 93 tune, sold, 2010 Challenger R/T 5 speed. 180 degree Thermostat, fan settings lowered, CC, ceramic brake pads, slotted rotors, red and black caliper paint, Challenger label for calipers, Corsa Cat back, functional hood ducts, and hood struts, 93 DiabloSport tune, Mopar drop in filter, JBA Shorties, Wideband O2, custome tweaked tune, Anti-sway bars front and rear, end links, strut brace, 12" subwoofer with amp.