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Discussion Starter · #1 ·
Hello all, New wrx owner here. I purchased an 05 wrx with only a cobb catted downpipe installed. I have a accessport v3 on the way in the mail right now, my question is. Am I okay to just do a stage 1 tune for now even though I have a downpipe? I want to wait untill I get a catback exhaust system before I go stage 2.. also, the car currently has 128,xxx miles. Am I safe to do a stage 2 tune without issues? Am I even safe for stage 1? Thanks for the replys in advance
 

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No. You need a stage 2 tune for a downpipe.
 

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Discussion Starter · #3 ·
Well currently the car is on a base map and is running fine, I've read it's okay but not recommended to run a downpipe with no tune, so would it hurt to just run stage 1 with the down pipe untill I get a few more parts I wanted for stage 2?
 

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Well currently the car is on a base map and is running fine, I've read it's okay but not recommended to run a downpipe with no tune, so would it hurt to just run stage 1 with the down pipe untill I get a few more parts I wanted for stage 2?

Yes, it would cause engine damage (and eventually failure) to use a stage one map on a car with an aftermarket downpipe.. The short answer as to why it would cause damage is that a stage one map is counting on the restriction of a stock downpipe. With an aftermarket downpipe the turbo operates more efficiently, and is therefore able to achieve higher load cells in the map than it would with a stock downpipe. At least with the stock map, those load cells are blank.. the ECU doesn't know what it should do in terms of fueling, timing, etc, resulting in predetonation and knock; which will damage the engine via extreme cylinder pressures. I'm not sure exactly how high the load cells are tuned in Cobb's stage one map.. but considering the fact that the car they used to develop the map on was running a stock downpipe I would assume nothing is tuned beyond the load levels that the car was able to achieve during their tuning process.

Why exactly do you want to wait to get more parts when your car already has the modifications needed to run the stage two map? Both maps come with the AP, and it's the exact same method to flash them.. so why would you select what you know is the wrong map, when you can just scroll down one line and select the right map for the car..

For what it's worth, all the Cobb OTS maps that come with the AP are base maps.
 

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Discussion Starter · #5 ·
Thanks for the detailed reply, it's gonna be my first time using an accessport so I wanted to get at least a cbe and install that and tune it all at the same time instead of twice. I guess it doesn't matter. But the car is totally ready for stage 2 with just a downpipe and stock exhaust system? And I'm just weary about adding that extra power with the mileage on the vehicle. 128k is safe for a stage 2 tune? All stock enternals the car only has a down pipe installed on it
 

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Thanks for the detailed reply, it's gonna be my first time using an accessport so I wanted to get at least a cbe and install that and tune it all at the same time instead of twice. I guess it doesn't matter. But the car is totally ready for stage 2 with just a downpipe and stock exhaust system? And I'm just weary about adding that extra power with the mileage on the vehicle. 128k is safe for a stage 2 tune? All stock enternals the car only has a down pipe installed on it

A catback doesn't change anything about how the car runs.. so unless you're paying for custom tunes, the stage 2 map you would use for an aftermarket downpipe is the exact same map you would use for downpipe and catback together.

Stage two should be fine at 128k miles.. if it's going to fail it's going to fail, stage two wouldn't make it any more likely to break down. Once you get beyond that, larger turbos and such, then you need to worry about the condition of the engine before getting into it. That being said, it wouldn't be a bad idea to do a compression test just to make sure the engine is healthy. If it fails the test then it will need to be rebuilt, and you might not want to spend the money on any more parts for a while.
 
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