Ok, I know this has been discussed before but I cannot find any solid answers to some questions I have. Every thread I find kinda ends with no significant answers or conflicting answers.
Sorry for drudging this up again....
My exhaust is rusting apart. My resonator basically rusted off and I had a shop fab in a straight pipe to connect it up again. Mufflers and cats are looking poor.
I want to redo the entire exhaust system. I don't care much about power gain/loss.
1. The Subaru rumble. From UEL headers which apparently don't exist for this car. Is it possible on the H6? Could it be achieved by adding some length to one side of the exhaust right after the header? (Between the header and first cat.) Or does the header itself actually have to be longer on one side?
2. Would I be able to replace the front cats with aftermarkets, and then bridge them to one pipe all the way to the muffler? (Deleting the bridge back to two pipes out the back.) I'd rather just fab one pipe all the way out to one muffler.
3. I understand the stock muffler has a valve for back-pressure. Can I safely use an aftermarket muffler without messing anything up? Once again, I don't car much about performance loss/gains.
All in all, is it possible to create the Subaru rumble in this car and is it possible to custom fab some exhaust with aftermarket headers/one muffler and not throw a CEL constantly. I'm willing to throw down some money if it is possible so throw me any of your ideas.
What kind of those Gen3 H6 cars are you talking about?? What kind do I have? Rusty? LOL
I have two Magnaflow 444504 high flow California emissions cats that replaced at least one plugged cat. I had the rotten egg stink, the cats death. Though not unlike a dead cat. I didn't chose those because they're high flow. They came recommended as something that, because they handle up to 4.6L of exhaust. Even if I had engine problems at a later time there is plenty of cat element to handle it and the extra flow wouldn't hurt anything either since I was tuning at the time.
Correct me if I'm wrong, but much of the "Subaru Rumble" is the result of the firing order of a Subaru 4-cylinder engine.
Left cylinders in blue, right cylinders in red:
EJ25xx says: "ONE! THREE! TWO! FOUR!"
EZ3xx says: "ONE! SIX! THREE! TWO! FIVE! FOUR!"
I'm not saying you can't make lovely vroom sounds with the H6- just that it isn't going to be that stereo-tactical Subaru™ ping-pong boomthrob. Just not possible with that engine.
Start this at 4:42,....and hear yeh ole Subaru Engineer Discussing the Subaru Rumble from the UEL headers,....and the lack of both on the 2015 WRX.
Maybe I should start making youtube videos and subaru would just give me access to the press cars to rip up and down the California wine country canyons too.
Yeah, that's what I was not sure about. I've never seen an H6 with the rumble so maybe the firing order along with the UEL headers is what does it. I didn't realize that.
Either way, I'm open to any and all suggestions on what to do with my exhaust, muffler type, aftermarket cats vs stock cats, single muffler vs dual muffler etc...
I'm no expert, but from what I've read, having a lot of diameter changes is not good. Scavenging is better if the pulses propagate evenly down the pipes so, try not to go from 2.25 to 3 ,then to 2.5 inches, etc. i dunno what the diameter is now, but don't vary from it too much and certainly not smaller.
So it looks like I'm better to just abandon that dream. Now onto the exhaust part of the business:
If YOU had my car what would you do. Clean slate from the end of the headers back. I'd like to try and find 2 aftermarket cats and then bridge them into one pipe all the way back to a single muffler. Any suggestions on cats/mufflers? Rest of the pipe will be custom bent and made at local muffler shop...
I didn't have anything other than a very subtle sound difference from near plugged cats to gutted cats to having the high flows I have now. Glad I wasn't paying for an exhaust note change because I'd have been disappointed with the result.
I stand corrected,...flowmasters despite their heritage, in this case are as quiet as OEM subaru. :smile2:
actually I like my subarus quiet,...and am only dealing with rumble due to a rusty exhaust muffler / a exhaust leak somewhere where I can't find it.
I guess I need to go into the V8 soundracer business,...so every H6er stuck with a car as whisper quiet as a Bentley, and then plug in to get something like this. and if I got one, I could get the sound out of 200watts of McIntosh glory. (that is still going strong).
I'm actually in the same boat. I have an 05 Outback 3.0R, and would love the classic Boxer rumble too. I'm wondering if the "rumble" has anything to do with the 3.0R only being available in an automatic transmission, and therefore isn't really a need for a catted down pipe, crazy aftermarket up pipe, divorced wastegate, blah blah blah. I was hoping that my local exhaust shop could come up with an idea on how to get that rumble. I've also heard that the drone in the H6 is a lot more common than in the 4 cylinder. "Ruby" is a daily driver, and I don't want excessive drone on my commute, but would really like some rumble.
watch what you buy,...I doubt you will ever be happy.
I still remember the guy with the XT and considering the "nameless" brand,...but also had a kid in a baby seat and was worried about excessive noise and the kid's ears. ....or just putting up with the daily "drone",...vs. being the once a week noisy bad boy when the kid was not in the car.
(small children should not be exposed to noises louder then 75db,...so a push mower is a little too loud).
I will meet with the exhaust guys mid June, and report back my findings. I actually just had somebody suggest new mufflers, get rid of the resonators, and get rid of the cats, and that should give the H6 that Subaru rumble. Not sure if that is a good theory, or complete nonsense.
how on earth are you supposed to pass a emissions or a ECU test without the Cats on a EZ30R car? (the o2 sensors,...the EGR stuff is all looking for the Cats to do the work),...unless you are turning this into a unplated race car.
Yeah, I was thinking the same thing. I did have Nameless axle back muffler deletes for a month. Obviously, it was the same concept as just hacking the mufflers off. Talk about drone... Holy crap, my neighbors hated me.
Subaru rumble...? Harley potato potato potato, but Subaru rumble? I sometimes have to check my tach to make sure the car is still running. I don't hear a "rumble" on mine, but, when I stomp the accelerator it makes plenty of enjoyable sounds. Might that be it?
I sometimes have to check my tach to make sure the car is still running. I don't hear a "rumble" on mine, but, when I stomp the accelerator it makes plenty of enjoyable sounds. Might that be it?
That describes my car. Get to a red light and yeah, check the tach. But as soon as the VVT goes full 50* of advance when I punch the gas the whole engine changes tone and goes all throaty and flies off. Still wouldn't call it a rumble.