Jomotopia's STi (Updated 9/12/09 - Stage 2!)

[six]

Take out the axle-back. Just leave the midpipe. Instant recognition and respect!!

Also, couldn't you just take an Impreza trunk from your local pick-and-pull and just paint it aspen white? No need to actually wait and get an aspen white trunk...

[jomotopia]

Take out the axle-back. Just leave the midpipe. Instant recognition and respect!!

might as well just run an open down pipe and be deafening!

Also, couldn't you just take an Impreza trunk from your local pick-and-pull and just paint it aspen white? No need to actually wait and get an aspen white trunk...

except there is never an 02-07 Impreza at the local pull a part places. i have an email alert set up with all the ones in the area.

[Standardshifter]

ruh roh, once the mods begin...

[Draklen]

ruh roh, once the mods begin...

people start going to the looney bin?

[watkins]

Take out the axle-back. Just leave the midpipe. Instant recognition and respect!!

might as well just run an open down pipe and be deafening!

What you do is sneaky. Dont fully tighten the bolts at the joint. If its the right kind of exhaust system and you do it right, some exhaust will escape and burble a lot, while the rest will go out the tailpipe. Thats how mine currently is after I pulled the exhaust after the cat just to see how loud it would be. When I put it back in, I guess I just didnt crank down the clamp enough. Sounds fantastic.

[jomotopia]

well, i installed my exhaust today!

it's a TurboXS stealth back. it's a huge 4 inch down pipe, high flow cat pipe, and mid pipe, that connects to the stock axle back.

i'll outline the install process below. skip to the next post for my impressions.

unfortunately for you guys, i don't have any pictures, as i had enough on my plate having never done this before.

i started the install at around 9:00 or 9:30 this morning. i had to get the car higher into the air than i ever have for oil changes in order to really be able to get to the exhaust bolts and have room to maneuver the pipes. this was kinda tough with my little jack, but i managed.

first i got under the car and sprayed all the bolts with PB Blaster to help loosen them for later.

first thing to do was remove the intercooler and turbo heat shield so that i could get to the bolts for the downpipe. getting the intercooler off wasn't too difficult, but the heat shield was a pain. some of the bolts were really hard to reach. but i finally manged to get it all off.

then i crawled under the car and unbolted the mid pipe from the axle back. this was actually pretty easy. i left the axle back in place since i would still be using it.

then on to the bolts holding the mid pipe to the cat pipe. for this one, i couldn't get a socket to both sides of the bolt, and that's when i discovered that i had not paid very close attention when i bought my gear wrench set. i needed a 14mm wrench, it had a 13mm and a 15mm. so, off to AutoZone to pick up a 14mm gear wrench. i get back and unbolt those bolts without too much trouble, and out goes the mid pipe.

now for the cat pipe. one of the stock bolts was broken! i got the unbroken one off without too much trouble. but the broken one would not turn, and it was stuck so i couldn't just pull it out. i tried several tools and couldn't get it to budge. so, off to The Home Depot to get some short pieces of pipe that i could put over my wrench and would fit in the space i was working in. got back and that pipe worked like a charm. out came the bolts.

but then i had to take the O2 sensor out. i had bought the special socket for it, but it proved difficult to get leverage to break it loose since i had already disconnected the pipe from the down pipe and it was basically hanging from the O2 sensor wire. i would have loosened it first, but i couldn't get to it while the pipe was in place. i finally managed to wedge it up against some of the underbody bits and get it loose. out went the cat pipe.

now for the down pipe. i had to unbolt this one from under the hood. it wasn't too difficult, even though some of the bolts were tough to reach. got it out and BAM, no exhaust! figuring i was half way through, i took a short break, and lunch arrived. as a funny aside, the delivery driver pulled up in an 06/07 Impreza wagon and told me he also has an 09 STI!

after lunch it was time to put in the new exhaust. first comes the down pipe. maneuvering it up from the bottom and onto the bolts was kind of difficult, but then bolting it up was fairly easy.

next was the cat pipe. bolted up to the down pipe pretty easily, but the O2 sensor would not reach its new location, the wire was too short! i had to break a couple of plastic clips that were holding it in place and pull and tug on the wire through some zip ties until i finally had just enough slack to get it to the hole and bolt it in. woohoo, 2 out of 3 pipes done!

now the mid pipe. i had to get it up in there between the cat pipe and the axle back that was still there. and the way this thing bolts up, the pipe can basically spin freely from the connectors. so it was kind of tough making sure i had it in the right orientation before tightening the spring loaded bolts to the cat pipe. once i got those bolted up abd slipped the pipe into the hanger, i bolted it to the axle back. i was done installing the exhaust!

yeah, but now i had to put back on the turbo heat shield and the intercooler. first off, i had to cut the heat shield, because it won't fit around the bigger downpipe. not too difficult with my trusty jigsaw and metal cutting blade. but then i had to rig up a way to put it back on. i had to move/bend the up pipe heat shield in order to fit the new down pipe, so i couldn't put back the bracket that holds the turbo heat shield. i was able to reuse one bolt location, and i had to make another hole bigger so i could use a left over nut and bolt combo to bolt it directly to the up pipe heat shield. it's a bit loose, and not that elegant, but it works and it doesn't rattle. this was a pain and took a while.

next the intercooler goes back on. DAMN that shit was a pain in the ass. it was damn near impossible. there are 2 hoses that you have to connect, and it is VERY difficult to get one connected without popping the other one off. and there is virtually no space to work in. i wrestled and wrestled with that thing. finally i had the idea to remove the driver's side bracket that the intercooler bolts to. this gave me a little more room to wiggle the intercoller around, and with a little persuasion, a screw driver, and lots of cursing, i finally managed to get both of the hoses on. put the bracket back and bolted everything back up.

i was done with the hardware! time for the software. i flashed Cobb's off-the-shelf Stage 2 93 octane map, which took about 15 minutes. then i fired her up. she sounded great! revved it a few times, watched for the CEL which didn't come, left it idling and crawled around underneath to see if i could feel any air escaping. everything looked good!

so now it was time to bring the car back to the ground. but, as i was about to do this, i saw something dripping from between the cat pipe and the mid pipe. damn it i had a leak!

so i crawled back under there to try and tighten the bolts up. and this is when things started to really suck. as i was tigenting one of the bolts, the wrench slipped off, and i punched myself in the eye at full force. it hurt like a mother f**k. my glasses got bent up too. i kicked on the garage wall out of pain and my wife came out to check on me while i was laying on the garage floor moaning and holding my eye. she bent my glasses back into shape and brought me an ice pack and a beer. i love that woman! but i had to take a little break.

once i recovered a bit, i got back under there and tightened those bolts, veeerrryyy carefully this time! i got them as tight as i could and put the car down on the ground.

it was now almost 6:00 PM

[jomotopia]

so then i took her for her inagural Stage 2 drive.

the first thing i noticed is that you can really hear the intake and the turbo. and the wastegate fluttering a bit when you dump the throttle. it sounds pretty cool. one thing that is a little disapointing is that the "vibrate the world" sound at about 1800 rpm (my slow cruise rpm) is pretty much gone. i guess this exhaust has a different resonate frequency (makes sense). but it does have a growl a bit lower, around 1400-1500 rpm.

torque down low is much improved. Cobb's site says peak torque is achieved at 3400 rpm instead of 4000, and it feels like it. the car also gets up and goes more at 2k than it ever did. power curve is more linear as well.

target peak boost for this map is supposed to be 17.5 psi. i had the Cobb AP hooked up for my test runs, reading out real time boost, and i saw 17.3 in 5th gear, but less in the lower gears. but i still need to give the ECU some time to learn and adjust. if it's not hitting 17.5 in the lower gears by next weekend, i'm going to try the Low Wastegate Duty Cycle map and see how that goes.

but, the butt dyno definitely shows an improvement! i am getting pushed back in my seat like i never have. i'm having to grab the next gear quicker, and she just feels fast again! i also managed to spin the tires on a left turn in 1st without even flooring it.

estimated increases, based on Cobb's dyno of their STi(s) is 300 hp stock to 350 hp Stage 2, and 300 torque stock to 385 torque Stage 2. you can really feel the increased torque.

i love it!

guess the next step some time down the road will be a pro tune so i can really get the most out of it.

[Roymond]

I'm really kind of depressed that the STi went to a hatchback design. Just seems kind of stupid. I like the look of the white, never saw one in any other color besides blue.

[watkins]

Sound clip!

[noob5,000,000]

Sound clip!

+1!

[Warner]

Dang, I didn't know stage 2 gave you such a large hp and tq boost. I thought it would mostly just flatten the curve and give you like 10-15hp or something.

We definitely need a sound clip.

[Warner]

Sound clip!

dddrrrrOOOOOO psh dddrRROOOOOOOOO psh

(sound clip for the deaf members of this site)

[watkins]

I dont think we actually have any. We arent entirely diverse. We have a huge majority of white folk, brown folk, and communists. There is a token Asian and black guy or two though.

[Leedeth]

token?

[Warner]

There's more than a token Asian guy. There's quite a few of them.