Official 3.6R Mod List

[KFCConspiracy]

I wouldn't do that personally... The 3.6R without any resonators from my experience makes for lots of drone. I'm cringing just thinking about driving in that.

[Scooby Fan]

Yeah...pretty much what I would expect.... big difference between a turbo 2.5 and an N/A 6 cyl. 3.6 too ......I was hoping someone had tried it and could chime in with first hand results...there are some Youtube vids of the 4th Gen GT's that way and they sound pretty good.

Just another idea that will never be followed up on

[GhiaAddict]

So I have seen that Subaru Parts Warehouse is having a 20% off sale till Jan 4th. I am thinking of buying the SPT Performance Catback Exhaust for 2008 WRX. Regular price is $650 shipped, with discount comes to about $530 shipped. Figure I could weld in a Vibrant ultra quiet resonator to make up difference in length. Any objections? Or should I spend my money elsewhere? This would be modded to go onto a 12 Legacy 3.6R.

[s2baru]

You can buy axle backs or have a complete system built for less than 600

[GhiaAddict]

You can buy axle backs or have a complete system built for less than 600

 

Now do you mean you can purchase the exhaust tubing, mufflers, resonators, flanges, etc. plus get the tubing mandrel bent, plus tig-welded all for under $600? I find that hard to believe, but I've been proven wrong before.

 

Where can I find the materials?

[s2baru]

Buy the axle backs yourself like vibrant or Magnaflow then have the mid built to adapt them to your liking in the cutouts. 3.6r isn't going to benefit much from a full exhaust unless you go wits headers like a select few have done. Focus on a hefty sounding axle back and call it good. Easily under 600 at a competent exhaust shop

[GhiaAddict]

So would you say that it would be better to purchase the headers and leave the stock exhaust? Maybe do a muffler delete, or remove the resonator?

[fredrik94087]

If you do headers, do the exhaust at the same time.

[GhiaAddict]

If you do headers, do the exhaust at the same time.

 

My vehicle will be improved in stages, so my question is would you buy the headers first or the exhaust. I do intend on doing both, but was thinking that I could do panel filter, headers, and tune on stock exhaust and do 5EAT tune as well.

 

Exhaust would be last as I feel they are more for sound then power..

[s2baru]

Well if you feel you want more sound than actual noticeable gains for power. Buy axle backs and call it day. Fredrick knows best that for "gains" just do the whole thing. Doesn't sound like $ is worth it to you because you answered your own question "more sound than power"

[cww516]

Well, there's some cutting and pasting required to get the headers to mate up to the exhaust, so if you're planning on replacing the midpipe at any point, you may as well do it when you get the headers. Guessing that's what Fredrik is getting at.

[GhiaAddict]

I assumed from the Raptor website that these 3.6 Headers were completely bolt on to stock cats?

 

I understand that there is welding involved when adapting a GT CBE to a 3.6R, but I thought the headers bolted to the stock cats. So you could technically run headers with stock cat and exhaust.

[KFCConspiracy]

Raptor's headers are not direct bolt-on. The stock midpipe needs to be cut, an step up adapter needs to be attached to the midpipe, and then the adapter needs to be welded to the pipe and the provided flanges. However, I don't recommend that you do it that way because the increased exhaust pressure from the headers will destroy stock cats.... It happened to me, it happened to perscitus, I'm sure it's happened to other members (That's all in this thread). Not to mention the fact that the stock section of pipe is thinner than the outlet pipe on the headers.

 

I would recommend you price out a pair of high flow cats, I used Vibrants, and I believe Perscitus did as well, and plan on having a midpipe fabricated when you do it. I paid around $1200 for my midpipe fabrication including parts using stainless tubing. I'd recommend you shop the project around a bit to your local speed shops. Show them pictures of perscitus's midpipe.

Edited December 30, 2015 by KFCConspiracy

[GhiaAddict]

Thanks for the info KFC... This makes sense now. I saw that Perscitus built a nice mid-pipe but didn't realize it was required, just thought it was for better performance. So on that note: header, mid-pipe, and exhaust will most likely be my last mods. Seems like easily $2k from Header to Muffler.

 

I will focus then on brakes and suspension first. Then I will do intake and retune (more for the 5EAT tuning), but I'm sure better MPG an power can be made from stock setup plus Intake.

 

Thanks for all the clarification on the headers.

 

Omar M

[fredrik94087]

My vehicle will be improved in stages, so my question is would you buy the headers first or the exhaust. I do intend on doing both, but was thinking that I could do panel filter, headers, and tune on stock exhaust and do 5EAT tune as well.

 

Exhaust would be last as I feel they are more for sound then power..

 

Difference between a dryflow panel filter and OE is 0 to 2hp if you could truly measure it. The panel filter with HKS snorkel was good for 5whp maybe 7...if memory serves correct. Look at the first page of this thread.

 

If you are looking to get power from the intake side, do the AFE intake. Look at page 1.

 

An exhaust that is done properly is power and, most unfortunately, sound.

[Spidermanswrx]

Mine headers still vibrate like hell and I spent over a grand I need to find someone or a place that could help. Someone needs to make a mid pipe for these headers. Raptor make some mid pipes.

[GhiaAddict]

Difference between a dryflow panel filter and OE is 0 to 2hp if you could truly measure it. The panel filter with HKS snorkel was good for 5whp maybe 7...if memory serves correct. Look at the first page of this thread.

 

If you are looking to get power from the intake side, do the AFE intake. Look at page 1.

 

An exhaust that is done properly is power and, most unfortunately, sound.

 

I have gone though basically everyone's build threads when it comes to 3.6R Legacy's. My thoughts for the vehicle are more for overall enjoyment then just all out power. After reading all the amazing builds, and after having built a few cars in my past, my idea is more along the lines of Less is more.

 

I feel getting car tuned by XRT even on a completely stock setup, will not only open up some power, improve mpg, but with the 5EAT tuning the car will just feel like a completely different vehicle. The panel filter, although not intended for all out power, will filter the air better than the factory filter and flow a little better than stock.

 

I feel the best area of improvement for these vehicles is brakes, suspension, and 5EAT tuning.

[Timothy.B]

I paid around $1200 for my midpipe fabrication including parts using stainless tubing.

 

This is why I've decided I'm just gonna do axle backs and be content with that, haha. What's the total amount on the whole exhaust? $600 headers, $1200 mid pipe with cats and $900 for cat back?

[GhiaAddict]

I haven't inquired yet, but can XRT tune the 3.6R to run catless without issues? I live in Florida where emissions tuning is not a requirement for registration. Also my car already has close to 70k so already out of factory warranty. Would cut the price of the midpipe dramatically if I dont have to run cats. Could replace with resonators.

[GhiaAddict]

Question, what is recommended for exhaust sizing? 2.5" or 3" piping?

[fredrik94087]

3". You have a 2.5"-ish exhaust now. I say 2.5-ish because it necks down to 2 3/8" after the resonator.

[KFCConspiracy]

You can definitely have it tuned not to care... But I will warn you, if you've never had a catless car, it will smell and it will be noisy, one of the most effective ways of muffling the noise your car makes is the cat. It may be debatable whether exhaust flow is still a bottleneck with the high flow cats.

[Golferdude1087]

Rattle solved by replacing the gaskets. Learned that the OEM gaskets can't handle the heat long term, so need replacement every so often

 

Sent from my VS986 using Tapatalk

Edited January 5, 2016 by Golferdude1087

[Golferdude1087]

 

I only have header, midpipe, high flow cats and an ultra quiet resonator.

 

Car looks stock but moves like a rocket. Recommend updating the sways and getting good pads/rotors as the power from the headers starts to show the cars limits.

 

As for mileage, I'm nearing 90k and she runs better then when she was bought at 40k. Headers not only make the car more powerful but puts less stress on the engine too

 

Sent from my VS986 using Tapatalk

Edited January 5, 2016 by Golferdude1087

[KFCConspiracy]

Golfer: I ended up finding a superficial exhaust leak between the header and the midpipe flanges on mine when I was changing the oil a couple weeks ago, not enough that I was getting exhaust in the cabin, but enough that I could feel some hot gases and hear a vibration. Ended up replacing those gaskets and coating the replacements with permatex ultra-copper RTV. No noise, no more leak.

 

Didn't think to take any pictures last time I was under there.

Edited January 5, 2016 by KFCConspiracy