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Catless dowpipe good or bad?

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18K views 15 replies 5 participants last post by  toda_power  
#1 ·
Hey all so ive got 2012 wrx with catlless downpipe and magnaflow catback. Wondering what is the best way to get it tuned and avoid any problems.
 
#3 ·
You will need a protune for that setup. Period. You should not be driving it at all until you are tuned. Park the car or put the stock downpipe back on it until you can get it to a protuner.

The only other option you have besides a protune is an e-tune.
 
#5 ·
Your post says that you have a 2012 wrx WITH a catless downpipe and magnaflow catback. So do you have these parts, just not on the car yet?

Catless downpipes are ok. But I am not a fan for several reasons. They can cause boost creep, especially on your model wrx, they are famous for developing boost creep with a catless downpipe. Although this doesn't happen to every wrx with a catless downpipe. It is hit or miss. But if you do get boost creep there is only one way to get rid of it. And that is switching to a external wastegate, which will cost some money. They also smell a lot. Without a cat a lot of the gases that are ejected from the exhaust have a very raw, bad smell. There are no OTS (off the shelf) maps available for a catless downpipe from the accessport. This meaning you can't use one of cobb's maps on their accessport, resulting in you have to pay for a protune or e-tune. Which isn't that big of deal unless you already spent 650 bucks on an accessport.

Catted just kind of simplifies things. They are not as susceptible to boost creep and can be used with cobb's maps.
 
#10 ·
ok. Like I said, a catless downpipe can be a headache. And no aftermarket downpipe is an item you can just throw on your car. They must be tuned for. There is a chance that a catless DP will cost you a good bit more money if boost creep develops.
 
#11 ·
Other than needing a custom tune, the possibility of causing boost creep (which will cost additional $$ to resolve), being stinky, trouble passing inspections, and negative impact on the environment.. I'd say catless is fine. The turbo will run more efficiently and spool a hair quicker than it would with a catted downpipe.
 
#14 ·
You could do that, if you have a good local muffler shop that will cut and weld on flanges for a good price.. like $50 or less. Going that route you won't have to tune or anything.. it will be much cheaper, and change the sound/volume of your exhaust will be fairly significant. On the flip side, there will be virtually no performance gain with just the catback.. installing an aftermarket turboback exhaust and getting the car professionally tuned will result in a significant performance increase, both in power, and drivability. A good custom tune should be healthier for the engine, improve fuel efficiency, as well as increase and dramatically smooth out power delivery.
 
#13 ·
You can solve the boost creep with an ewg from what I've been told.

I have a catless DP, it reeks, my exhaust tips are impossible to keep clean, and I've got to keep an eye on the boost because of problems with boost spikes.

I would opt for a catted system if I had to do it over again

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