covertrussian

Make sure your exhaust tips stretch past the rear bumper. If they don't, the noise will get caught up in the bumper and travel up into the trunk.

Thanks everyone for the kind words! There are a few bushings that I haven't done yet, and probably wont if increases engine/driveline vibrations, for those I'll do my best to find another person's instructions and link them here.

You guys made me get off my lazy butt and finally post this up: Complete Bushing Guide for BL/BP

Complete Bushing Guide for BL/BP This thread is a one stop shop for all of the bushing part numbers and replacement instructions for the 2005-2009 (BL/BP) Legacy. Front Suspension Lower Control Arm Forward Bushing - Instructions LCA Forward Bushing Part Numbers AVO - S2C08G1GV057T Nolathane - REV028.0004 Powerflex (street) - PFF69-501 SuperPro - SPF3091K Whiteline - W0506 Rearward Bushing - Instructions LCA Rearward Bushing Part Numbers AVO - S1X03E1GV001T SuperPro - SPF2801K SuperPro (Caster +0.5) - SPF5112K SuperPro (Caster +0.5 ALK - Outback Model) - SPF3094K SuperPro (Caster + 20mm ALK) - TRC3095 PowerFlex (Street) - PFF69-505G Siberian Bushing - B00Z9WFALI Whiteline (Caster +0.5) - KCA334 (Adjustable) Whiteline - W53353 Front Anti-Swaybar SuperPro "Standard Size" - SPF3096-21K SuperPro "18mm ID" - SPF3096-18K or SPF3096-19K Whiteline - W0406-20G Steering Rack - TO DO Steering Rack Bushing Part Numbers Avo - S1105M1GVUSAT Energy Suspension - 19.10101g Prothane - 16-701-BL SuperPro - SPF2889BK SuperPro - SPF2889K Whiteline - KSR207 Rear Suspension Trailing Arm (Forward Knuckle) - Instructions Trailing Arm Bushing Part Numbers Nolathane - 46333 SuperPro - SPF3388-70K Whiteline - W63398 Upper Control Arm - Instructions Outward (Knuckle Top) Part Numbers SuperPro - SPF3389K Whiteline - KCA399 (Adjustable) Whiteline - W63397 Inward (Subframe) Part Numbers Nolathane - REV050.0026 SupePro - SPF3390K Whiteline - W63396 Toe Arm - Instructions Outward (Bushing is in Knuckle) Part Numbers SuperPro - SPF3392K Whiteline - W63394 Inward (Subframe: Toe Cam Bolts) Part Numbers Whiteline - W63395 Rear LCA (Forward) - Instructions Rear LCA Part Numbers SuperPro - SPF3391K Whiteline - W63393 Control Arm Kit Whiteline Trailing Arm Kit - KTA124 - Replaces all of the lower arms, but you will still need bushings that reside in the knuckle and upper arms. Rear Subframe Subframe Inserts SuperPro (Upper & Lower, for vehicles with voids in upper and lower bushings) - SPF3007K SuperPro (Lower Only, for vehicles with solid uppers) - SPF3008K Whiteline - KDT902 Drivetrain Rear Differential Void Filling Inserts - Instructions Whiteline (Rear Voids only) - KDT927 Whiteline (Front & Rear Voids, 2008+) - KDT903* (2005-07 have solid bushings for front differential mount, while 2008+ has Rear Diff Forward (Outrigger) Bushings Whiteline - KDT905 Rear Diff Rearward Bushings Whiteline - KDT906

I don't have much experience with those. I've tried layering the butyl sound deadening mats, but it did melt a bit. I didn't notice a difference because my setup is quiet enough not to matter.

The cats actually help reduce the noise a lot, that's part of the reason it was louder. But chassis design has some to do with it too, on a sedan the trunk and seats sound deaden a good bit, while on a wagon it all resonates in.

Aha! The twin tip one is probably very quite:

The inlet pipe to can ratio is good on those Max. It gets trickier when you want to have a 3" pipe, since most mufflers will be only 4-5". The bigger the can, the quieter it will be, even in straight through design.

I just changed it, got tired of people butchering it either the comfy part or the STI part. Now it's a little more self explanatory.

Resonator helps reduce the higher pitched "raspy" noises on cars, but the inefficiency of unequal length headers already does that, thus resonators don't seem to do much. A lot of aftermarket exhausts use too small of mufflers, there's just not enough volume in them to reduce noise. Your options are to go back to stock, which honestly is more then sufficient for these cars (if mine wasn't so rusty I would've went back too, since gains were tiny). The alternative is to start hunting for better/bigger mufflers and paying a shop to fab it in place.

I did yes, increasing the internal diameter of the line raised the harmonic frequency to be well above the normal RPM ranges that my car ever sees.

You got it

Depends on the downpipe and version of it, my version of GS downpipe has the O2 bung past the cat, so the readings would be off. I heard newer versions of the GS downpipe have the bung before the cat, so that would work fine for those.

Sorry for the confusion, I meant they use the same temps, that's not to say they will or will not fit. I installed 21200AA200, which is for EJ253 Legacy and Outbacks and is 88C: https://parts.subaru.com/p/Subaru__/THERMO-ASSEMBLY/49231072/21200AA200.html Here's part numbers for the various years: 2005 GT: 78c(172f): 21200AA072 (Stock) 2010-12 GT 84c(183f): 21200AA230 (Should fit because EJ255) 2012 2.5i 88c(190f): 21200AA200 (Confirmed Fits) 2020 Ascent 88c (190F): 21210AA190 (will not fit, but same temp range): https://parts.subaru.com/p/Subaru__/THERMO-AND-GASKET-ASSEMBLY/49231121/21210AA190.html I do have a Paypal account and will admit my testing has slowed down due to tighter budget, harder to justify almost $20 in gas, just to test a part. If you want to be generous and would like to contribute to the testing gas money fund, send me a PM .

Factory is 172F, so it's extra 20F. Probably though especially on hot days, but you can pull timing via ECT correction table. Also any efficiency gains will be negated if you don't adjust the radiator fan tables to be higher (factory fan is on at 203-205F...). The reason I went with 190F, is because the Ascent uses 190F temp range too, while 2010-12 LGT uses 182F (10F warmer then ours, fitment unknown). Also my NA 2012 Outback uses a 190F stat, that DOES fit, but since it's NA it has less heat to worry about.

It's a 192F thermostat, but as with all thermstats car always cruises 8-10F warmer then the stat it self (with fans off). I went with the higher end extreme to see if thermal efficiency goes up.

They do, but that's where my wideband lives, so that I'm not blind to what the car is doing . I could perhaps tap into the aftermarket O2 for the closed loop operation, but that seems pretty complicated on it's own. As for moving the front o2 sensor to downpipe, since the sensor is going to be further away, there are some delays in reading that will happen. Plus it a much less hostile environment, so some O2 related tables might need tweaking.

I'll do a detailed post about it, if I ever do do it. I just don't want to drill and weld my GS downpipe

Ooo that's probably it. Maybe you should relocate the O2 to be behind the turbo. That's something I'm wanting to do myself too, but I have too many projects to do still heh.

Are you running really rich or lean? What kind of header you running again?

Might be much easier on the Legacy, it does have much bigger brakes. Either way let us know how it goes! Lets just say my cruising water temp is 200F even at freezing temperatures. I'm not sure it will be good for summer though. Last set I got was from RockAuto early last year, they were $8ish for Iridium SILFR6B8's, but the same ones are now $11ish at RockAuto. Makes me concerned that I got knockoffs and I didn't take any good pictures of them either, but the car is running fine, so I think it's all good. I forgot your gap question, the more boost you run the smaller the gap you need to avoid spark blowout. You want the run the biggest gap you can without getting spark blowout, since it exposes more of the spark to the air and fuel mixture. If the car runs better with a smaller gap, that means your getting spark blowout with your boost levels, or your coils are getting weak. I personally used to sidegap, old copper trick, so my gaps were bigger then normal. With B8's I'm running the upper end of factory spec (0.028-0.031).

I haven't seen/heard of Denso ones myself yet, but that was referring to this mostly: https://legacygt.com/forums/showthread.php/counterfeit-spark-plugs-281452.html

If you installed it, I wouldn't, just seems wrong. But if it looks like a fake, I definitely would return it. Especially since Amazon is getting more and more fakes now days in general.

I've tried using those clips on my other cars and they were such a pita to install that I don't think I've ever even used them. IMO the gains are gonna be very tiny, if at all. Raise one of your wheels, see if you can rotate it (going to be limited amount of movement thanks to AWD). I can do it with one finger on my Legacy. As for the plugs, those LFR6BHX seem WAY too cheap. Make sure you're not getting counterfeits: https://legacygt.com/forums/showthread.php/counterfeit-spark-plugs-281452.html Finally, I've been doing a lot of testing in the background, but as usual the external factors have been really limiting me, so I have to swap in parts back and forth and it's just getting frustrating at this point. Right now I'm testing a warmer T-Stat, hope to have some updates in coming weeks.

Which ones are you buying and where from? Back in 2013 I bought the Denso 234-9120, 58k miles and a few header swaps later, still reads true (I watch the AEM Uego often while driving).