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Discussion Starter #1 (Edited)
Here's pretty much how its gone with my spec in the 15 months I've owned it...

Test drive - it sounds awesome! Nice growl, excellent sound!

Gut the manifold - couldn't wait for a header, had nightmares of cat dust infecting the combustion chambers... now it sounds terrible. Buzzy, poppy, raspy... the worst kind of exhaust noise!

Added ebay header - nice power increase! Changed the noise significantly, not better, not worse, just changed. Something must be done!

Decided to make an exhaust. Partially because I'm too cheap to buy one, partially because I wanted to use a resonator that would be sufficient to control the qr25's abundant noise.

Goals:
1 Sound cool
2 Don't annoy wife
3 Fit good
4 Performance
5 Look cool (to me)

Parts used:

2.25" aluminized
U-J mandrel
Vibrant ultra quiet 1140
Old greddy Evo2 axle back
V-band clamp for axle-back
$_57.jpg

I chose the greddy because it looks great, the hangers were already there which saved me a lot of work, and because of brand snobbery. I've always liked greddy. I figured since the muffler was so old it was probably doing nothing for sound control so I chose what I thought was the baddest resonator possible for controlling stupid exhaust noise. I also chose 2.25" because it's a 2.25" mandrel is waaay better than the stock crush bent stuff, and I really have to have good sound and fitment more than anything. Remember performance is priority 4.

In progress!
2015-10-22 23.02.48.jpg
All tacked together!
2015-10-16 20.39.00.jpg

2015-10-16 21.27.33.jpg
2015-10-16 21.26.10.jpg
2015-10-16 21.29.37.jpg

Edit:

The exhaust is finished! I'll give the results according to my goal criteria.

Goal 1: Sound
Well, it's not quite what I expected. With 75% or less throttle, it sounds great. I'm 100% satisfied with the sound during 99% of the driving I do. However, if you stab the throttle for a static rev, over 2500 rpm or so the sound starts to distort and make a buzzy ricer kind of noise. If you rev it a little softer the buzz is not present. At WOT the same thing occurs at about 2500+. I have to fix this, because fixing the sound is the top priority.

Goal 2: Wife test
With my daughter and very pregnant wife in the car, we made it half was to the hardware store before I informed my wife that I had changed the exhaust. She didn't notice. GOAL 2 SUCCESS!

Goal 3: fit
Fit is good, the Scott Russell link hits the exhaust on hard bumps. It almost never happens, so I'd call this a success. But what sucks is that I had a screw jack holding up this corner of the suspension when I welded it together to simulate normal ride height... but it wasn't quite enough. Still satisfied with the fitment. No leaks!

Goal 4: Performance
Who knows? It's louder, so it's kinda hard to tell. The cars quick, I'm happy with the power. Obviously I wish I had before and after dynos, and 1/4 mile results. I'll just call this a success.

Goal 5: Looks
Success! Of course that's a matter of opinion!

STAY TUNED for stage 2 where I try to fix the ricer buzz!



***After stage 1, 2, and 3, ITS FINISHED!***

Read through the thread for the details, but here are the results:

This is my phone in its holder, with a view of my broken console bin. Sorry its quiet, best I've got right now! Turn up the volume!

1st and 2nd gear, spinning my snow tires on roads that have been graveled.

Cambered on ramp, 2nd-3rd.
 

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Nice upgrade brother. The QR25 can sound verry nice with the right parts

I'm near Eugene hit me up if you ever wanna cruise the Spec's
 

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Double post
 

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Discussion Starter #9
Nice upgrade brother. The QR25 can sound verry nice with the right parts

I'm near Eugene hit me up if you ever wanna cruise the Spec's
Thanks man! I grew up in Eugene and my mom still lives there. I'll pm you next time I visit!
 

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Discussion Starter #10
Thanks yogi, v2, allblack! I updated the original post with results.

Mirror I didn't touch the mid pipe, so the stock cat is still there. I don't dare run the stock na qr25 with no cat lol.

More to come guys!
 

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Discussion Starter #11
Constructing a performance exhaust STAGE 2:

As I stated previously. There is a buzz that my new exhaust experiences at WOT or quick stabs of the throttle that is ricey and unacceptable.

I made the educated guess that my 10+year old greddy muffler was probably useless in terms of deadening sound, and that it probably doesn't look like it did when it was new
592324696_LnM3q-M.jpg

So I cut that thing open to find out!

2015-10-17 07.54.53.jpg

Didn't look to good, so I used some FMF motorcycle muffler repacking material to attempt to restore is performance. One pack was sheets, one was loose bulk stuff. Total cost of the repack was $22.
2015-10-17 07.55.20.jpg 2015-10-17 07.55.50.jpg
 

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Discussion Starter #12
View attachment 65649

View attachment 65650

Had to fill some rather large gaps. My welding was not it's best but got the job done.
View attachment 65651

View attachment 65652

All done!

RESULTS:
The exhaust is about 15% quieter, it is also a deeper tone. It sounds more muffled...however, the freaking buzz is still there. Maybe it's better, I'm not sure, all I know is that it has an intense buzz/crackle/snappy kind of distortion under WOT conditions.

I'm still not giving up on this, I just expected that the resonator/muffler/piping diameter that I used would be safe from ricer buzz.

I welcome an educated discussion on how I could go about solving this problem.

The exhaust consists of the following:

Cheap ebay 4-1 header
Stock midpipe and cat
2.25" piping
Vibrant ultra quiet resonator
Greddy Evo2 Repacked

My initial plans on remedying this problem in order:

1Adding a bottle style resonator
2Replacing the greddy with more of a muffler instead of a can
3 looking into a higher quality header.

Really not excited about #3 because I have no idea what header would make the sound better, plus it's the most expensive option. Also I have no idea what known good headers for this car are still sold.
 

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^^^This is how we do in Oregon, keeping the old stuff alive! I love it nice reconstruct I'm impressed.
 

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I have an aero turbine xl (now jones turbine) and love the sound. I think they only make in increments of 0.5, but you can always check with them. They make a muffler/resonator combo in one. I use it as my resonator. Priced usually around $60-85.
 

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my hunch
studying the greedy tin can

i imagine your 2500 rpm static buzz is coming from the thin greedy tip

if you have a 2 jr rubber band wrist thingie,
slip it over the cold tip and rev for a sec, see if that changes the buzz

[or wrap with blue paint tape, do not allow to get hot, just a quicky test
or with a gloved hand, hold just the tail pipe tip for a sec]
 

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Discussion Starter #17
I grew up in Oregon, Klamath Falls, Got stationed in Florida when I was in the army, and discovered that I didnt miss 7+ months of winter at all, Loving the 9 months of summer down here in the south!
Well Klamath Falls is certainly not what all of Oregon is like. In the valley there's maybe 1 week a year of Klamath Falls winter, but there is a lot of rain. Where I live in the gorge we get about 11 inches a year of rain. Crazy crazy differences in landscape in this state.

Wife and I visited TN last year, and I would move there in a heartbeat. Really enjoyed it there.

I'll look into that muffler/res mirrortints, never heard of them before. Thanks

Yogi, I never thought of that. However, I don't know why it would cause a buzz now if it didn't when it was brand new (I'm assuming it didn't buzz like this when it was new). I'm fairly certain that replacing this straight through can on the end with a real muffler like a vibrant or magnaflow would solve my problem. But that would be about 2-3x the cost of adding another resonator.
 

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I don't know why it would cause a buzz now if it didn't when it was brand new (I'm assuming it didn't buzz like this when it was new). I'm fairly certain that replacing this straight through can on the end with a real muffler like a vibrant or magnaflow would solve my problem. But that would be about 2-3x the cost of adding another resonator.
Get a Skunk2 Muffler, worth every penny. A cat, resonator and skunk2 muff sound deep and bassy with zero rasp and a nice little burble every now and again in between gear shifts that just brings a smile to your face. Dont get mistaken for a Honda or something with all that rasp lol j/k

I'm buying a 2jr header, midpipe and side exit exhaust soon...you can have my setup for cheap if you want...
 

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If you ask me buzzing noise is probably from that cheap ebay header, I bet that system would sound real good with a proper header.
 

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Discussion Starter #20
STAGE 3:

This one took a while.

Stage 3 was not so straight forward as the work done thus far. A bit of background... I've been going to school for engineering at night for the past 5 years. Within the last few months I left Nissan for an internship. So this is the first time in 10 years that I haven't worked as a mechanic.

That also means no lift, no welder.

So I started here,
2016-01-13 21.00.40.jpg

It's a decent welder, the money isn't there yet to get all the necessary mig components. Right now I'm running it as Flux core, so it's not as clean as the welds I did with the Lincoln at my old dealership.

Next step

2016-01-13 21.04.39.jpg

Now it's late, and I have to get up at 4:30 am for my new job. I'll conclude stage 3 tomorrow.

STAY TUNED
 
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