First what is the major difference between the Stg1 and Stg2 maps. What does Stg2 change that you need a downpipe/TBE.

Second, will a punched-out stock exhaust work for a Stg2

Third, if no, why? What variables are changed that REQUIRE a more free flowing exhaust? Changes in timing? fueling? boost? What is it?


And my last question, I plan on running a MBC with stg1. Raising boost to approx. 1.1-1.2bar, that will inevitably fluctuate in relation to ambient temperatures, regardless I'm running the Stg1 because it will automatically make the changes across the table for me. If I can punch my cats and run a stg2, then I plan on doing that.

you have 02 wrx right? if so, you well also need a uppipe and downpipe like the helix. you can use the stock catback exhaust but recommend to get a 3" catback for better flow. i wouldn't use a mbc with out a downpipe thats what i heard.

you have 02 wrx right? if so, you well also need a uppipe and downpipe like the helix. you can use the stock catback exhaust but recommend to get a 3" catback for better flow. i wouldn't use a mbc with out a downpipe thats what i heard.

Ok I can do the UP and DP but I'm looking to keep the stock muffler.... and I don't have the cash to throw down for an overpriced "stealthback".....


mbc doesnt really change a whole lot... just hit boost sooner compared to the stock boost table.. since its a pre-04 the fuel is there....

Basically I want it to LOOK stock, but I want to push every last pony out of the engine. Dangerous? Yeah, but I'm looking into a 2.5L upgrade so this will give me a sooner reason to do it.

I didnt like the progress of the car, so I took it back to stock and I'm re-doing it.