Just put loaded up the APv2 on my 04 WRX yesterday and wanted to give my impressions thus far on performance. Installation was quick and easy. I took it for a drive immediatley after I loaded up Stage 1 for CA/NV/AZ 91 octane.

Since I did not have a boost guage, using the live data function on the AP was the first time I was able to see what I was boosting. I was surprised to see I was only getting 7psi in first gear and 11psi in second gear. So I checked the forums and heard that you must let the ecu work its magic for a couple miles before you feel the full effects of the reflash.

Well after work today I did a few hard pulls and saw 11 psi in first, 13 psi in second and 14 psi in third. I could definately feel a difference... I wonder how much more goodness there is left for the ecu to extract :devil:

Update: I did the Vishnu ecu reset trick today and I am really impressed with the results. I am seeing the same boost levels just better acceleration - both on and off boost. There is no doubt in my mind that cobb has delivered their estimated 33hp/40tq even with the piss for gas I put into it here in cali.

The Vishnu reset is a must after every reflash!

Update 2: Just put on my 3" downpipe and reflashed to stage 2 for CA/NV/AZ 91. It feels less responsive compared to stage one and although I noticed an increase in top end it is definately not as much as I expected - even after the vishnu reset and a week of driving it.

Im guessing that this is because the map is designed to work with so many different exhaust combinations - compared to the stock map where it can be more specific.

My mods are: prodrive 2.5 axle - stock 2.25 resonator pipe - 3" EZR downpipe (which I dont recomend)

I was thinking about just reflashing back to stage one, since it had so much better response... Any comments?

may I asked why, you don't recommend the ERZ downpipe?

You got a funky little TBE exhaust going there, hehe

3 -> 2.25 -> 2.5
I'm suggesting on getting an intermediate pipe 3inch down to 2.5

BTW, if you have a downpipe, stay stage 2, stage 1 is meant for stock

If you're unhappy with stage 2, why not get it protune

Well, what would be the downsides of going back to stage one? I doubt it will run lean... Im not going to get a protune just yet so Im tring to feel out my options.

As for the frankenstien exhaust:

I purchased the prodrive axle because of the sound quality. I wish it was full 3" but Im willing to sacrifice a few hp for sound.

I'm thinking about getting my resonator pipe replaced at my local exhaust shop with a 3" to 2.5" straight pipe. Im just afraid it will screw up my exhaust note.

I dont recommend the EZR because:

1) The gaskets included are not usable because of fitment and quality issues
2) The fitment was off by about one full inch. What I mean by that is the downpipe points toward the ground and towards the driverside by about an inch of where it should bolt up to the resonator pipe.
3) For about 50 bucks more you can get a good quality, good fitting used downpipe.

I'll let the others chime in on why you should stay on stage 2 instead of stage 1

Getting the 3-2.5 pipe should not mess with the sound, especially if you get a resonator, might get a tad bit deeper rumble

My ERZ was fine, that's why I asked why you did not recommend it, but I've read some mixed review, so I guess it's normal.

sry for bother! i have a 07 WRX all stock! if i buy a cobb AP only to go to stage 1 for driving a couple months, will this hurt my car without any other mods? sorry for that noob question!

Stage one is MEANT for a stock car. So no, it will work perfect, just as it was designed to do. :)

Update:3

I tried out going back to stage 1, even with my 3" downpipe and 2.5" axleback. I was not at all surprised to find that under 3500 RPM it pulled harder than Stage 2. After 3500 it felt like it just flatlined. Stage two definatley had the right tune in later RPM.

Hopefully Ill have a maddad 3"-2.5" halfback intermediary pipe next week. Maybe that section is robbing me of my bottom end, we'll see...

The reason to use stage 2 map as opposed to stage 1 is because you should use what was designed for your mods. I read a quote somewhere (I think it was in Maximum Boost, but Bell might have been quoting someone else) that sums this up nicely "You always make maximum power right before blowing the engine up".

Specific reasons include but are not limited to the following:

When you go from stock to stage 1, the WGDC is increased to allow you to hit higher boost. Now that you have removed most if not all of the exhaust restriction a lower WGDC is needed to hit your target boost. If kept at stage 1 levels with a turboback you will be much more likely to overboost and could possibly kill your engine.

If you want more power go with a Protune. Stage 2 definitely evens out the power. Your but dyno might say less but I am betting you are making more.

Well, Im not running the stage 1 map right now, I just used it for a quick run to confirm my suspision that I lost some low end power. Right now I'm actually running the economy map and getting about 25 MPG :) . This is a nice improvement from stage 1 when I got 21 MPG and a huge upgrade from the 18 MPG I was getting from stage 2 :mad: . Hopefully Ill get better milage from stage 2 with the new 3" pipe. (less restriction-more horsepower-leaner fuel curve?)

I'm hoping that the only reason that I lost that power is because of the ristrictive 2.25 resonator pipe. We'll see when I put in the 3" intermediary next week.

Eventually I will get it professionally tuned, but not untill I am done modifying the car. It doesent make sense finacially to get it tuned after every mod, although I wish I could.

Still waiting for the MadDad to ship... the local member I bought it from hasnt had the time to ship it out yet.

Wanted to let everybody know that after driving on the economy map for 2 tanks, I am not impressed with the city gas milage. My first tank was virtually all highway milage and I was pleased with the 25 MPG I recieved. My second fill up was all city driving and I got 17 MPG average. I attribute this to the lower boost setting used with this map. I hit full boost sooner than stage two so its impossible to stay out of boost in the city.

I recommend only using the Economy map for road trips - use Stage Two for city driving.