I've been driving my 06 wrx for over 3 years now, and I think it's finally time to make the leap to stage 2. I've got an SPT catback on, and have been running stage 1 with an AP for a couple years now (I know there are some AP haters out there, but I like the ease and reliability of it). So I wanted to get some opinions before I buy a downpipe. I've been thinking about going for a catted one, mainly because I'm sure the wife wouldn't like the car too loud, don't want to get hassled by cops, and/or piss off the neighbors too much. Of course, I also don't want to sacrifice too much power, etc. The downpipe I've been eying is the Cobb catted downpipe - anyone ever heard the SPT catback/cobb catted downpipe combo? I've also toyed with the idea of running the Cobb catted dp with my stock cb if the car was too loud with the cobb and spt, but would that be too restrictive? Oh yeah - and would I also need to buy a new turbo heat shield? Any advice would be very appreciated! -Jeff
Really, all downpipes are created equal (provided they fit). As long as you don't get one that blocks off the WG opening (eg, hks), you'll be fine. Of course, a highflow cat will lower the noise level as well. The stock WRX catback is quite restrictive, so I'd recommend staying with an aftermarket CB if you can deal with the noise. I won't question your choice of EM, but for what it's worth, I've found the Cobb basemaps extremely unreliable. They make good consistent power on some cars, and run terribly on others. So yeah, I'd recommend a custom tune. As long as you'll take some criticism of your mod choice, I'd suggest the following: -TurboXS stealthback (catted if you're looking for low noise) -3-port BCS -Custom Tune If you ditched the AP, you could probably do all of that for a very low cost out of pocket.
My $.02 is I'm with you, I don't like super loud exhaust for daily driving. I have a catted downpipe and it brings down the tone a bit. If you want a heat shield you'll either need to hack up your stock one or buy a new one. As for the sound, I personally haven't heard the spt with the cobb, but I know SPT, Cobb, and maddad are some of the more quiet aftermarket exhausts.
Great advice - I have indeed considered getting a custom tune. I'd probably start out with the AP right after I get the hardware in place (since I've got the AP already it would be an quick and easy start), and if that works great, otherwise get someone to tune it. About the only thing I'd rule out is custom tuning it myself. Thanks guys!
I'd also suggest you take a look at open-source for EM once you get to that point. There are dozens of threads on here regarding the positives and negatives of both, so you should be able to easily do your homework and pick the best solution for you. Additionally, if you'd like to see some technical details as to what my 06 WRX did at each modification stage, there's a thread in the Tech Tips/Noob section, here's a link.
I've been looking for info like this ever since I got my car (especially since I have the same car)! Thanks that does give me a really good idea of what to expect from each mod. I wonder how the SPT axelback compares to the stock.
There is alot of good advice in here so far. One thing I would like to add is that using a catted-DP vs. a non catted DP will show very little in gains assuming both a good pieces. Realistically you would probably only gain a couple HP,TQ and maybe a little bit faster spool by going catless. So if you want to keep it quiet go catted, you will still be happy with the gains.
If you've got the money go catted, the drone of the catless turboback made me want to blow my brains out.
