Bessie II - Enlight's '05 6mt Matte Blacke Wagon

Drove up to Harriman State Park and Bear Mountain for a joy-ride today - never knew how great the roads in Harriman were. Lots of on-camber hairpin turns with changing elevation. Saw a lot of sports cars and motorcyclists out as well. Changing the coilpacks eliminated the stutter issues, and no more shaking in the front suspension since tightening the control arm castle nut. I'm regaining some of my confidence in this machine again.

 

However, I'm still having problems with the car pulling right on acceleration. I'm going to swap the tires and re-tighten the sway bars, this time at driving ride height. If that doesn't do it, I read on NASIOC that a bent crossmember can change the control arm arc.

 

This reminded me that at one point my Rallitek skid plate was bent and my shop had to torch and hammer it to get the bolt hole aligned again. If something hit the skid plate hard enough to bend it, it's possible it bent the crossmember as well. I do remember one time I drove over what I thought was a large snowball, but it hit the skid plate hard enough to reverberate. In any case I'm going to measure the crossmember for square.

 

Edit: Also adding my last alignment sheet in case anyone else has ideas.

Edit 2: For posterity, I just realized I can use a smoke machine to locate my fuel leak. Much cleaner than topping it off again and rushing home to get it on stands.

Edited March 27, 2020 by Enlight

Drove up to Harriman State Park and Bear Mountain for a joy-ride today - never knew how great the roads in Harriman were. Lots of on-camber hairpin turns with changing elevation. Saw a lot of sports cars and motorcyclists out as well.

 

Harriman/Bear Mountain is a great place to drive around and hike. Thanks for the idea of a smoke generator to look for fuel tank leaks. I might be needing to do that soon as well.

how'd that JDM to USDM harness work out for you?

I haven't gotten around to installing it yet since I need to flip the projectors in the headlights - will report when I do!

 

 

Inadvertently filled my tank all the way up again but I was able to get home and take a look in time - the leak is coming from a seam that's facing the front of the car - I was able to see the droplets form. Summer project is to get an '09 tank from a junkyard and POR-15 it.

 

 

Tightened up castle nuts on tie rods, motor mounts, subframe brace, and exhaust hanger. Switched front tires and went for a ride - now the car is pulling left. Glad I isolated the pulling issue. I'm also still getting a clunk in between shifts. It may be the pitch mount but I remember tightening it down good. Maybe I put it on backwards.

Edited March 31, 2020 by Enlight

 

Went for a joy ride yesterday starting from Queens ending up in Catskill and took the Taconic back down. Swapping the tires around eliminated the pulling under acceleration. Just goes to show that it's best to keep things simple. To think I was going to check my crossmember for square...

 

Living true to my title (Parts Cannon Bombardier), I saw a lot of oil under my engine so I went ahead and order new valve covers and a PCV valve. While I was under the car today, I wondered whether the oil was coming out from the dipstick tube that I remembered I had trouble re-installing the o-ring with. I pulled the tube out and lo' and behold, it was missing the o-ring. My valve covers were fine. That's another $120 worth of stuff in the parts closet.

 

I lost enough oil that my dipstick was reading empty. I had to put nearly 1 1/2 quarts in it to get it back to 3/4 fill mark. There needs to be an award for stupid on this forum.

 

 

With the little salt that remained, I was also astonished by the amount of salt that I found under the car. Now I understand why heat wrap can trash headers so quickly. All the salt and water gets absorbed by the wrap and promptly starts getting to work. I sprayed the wrap on the headers with high temp paint to prevent wrap-soak but didn't hit the midpipe. You can also see all the salt that accumulated on my exhaust. The drip that looks like oil is actually rust converter. I'll be painting the cans with high temp paint some time in the future.

 

Began the sound deadening process by applying CLD tiles I had from Sound Deadening Showdown (before they closed) and Dynamat I purchased from eBay with eBay bucks. More CLD is on the way from Resonix along with MLV from TMS. Also stuffed Rockwool SAFE'n'SOUND insulation into the rear liftgate, spoiler and rear quarter panels areas. When doing the quarter panels areas make sure the rain hose doesn't get disconnected, they are only friction fitted. PPE is still required when installing the insulation.

 

 

 

 

 

 

 

 

I installed a mass damper today and I'm frankly very surprised by the dramatic change it's made. Attached are graphs of the frequencies I analyzed using the app - the first two are before damper, the latter two are after damper. From the "before" you can see that much of the frequency is around 25hz, from the "after" the frequencies at 25hz are almost eliminated. These recordings were all done at approximately 80mph and 3,000rpm. The math below also falls close 25hz, which I found pretty interesting.

 

 

 

Ignitions/second = (3,000 rpm / 2 [for 4 cylinder engine with ELH]) / (60s) = 25

More importantly, the subjective feeling of driving the car is pretty dramatic. The droning, almost buffeting, sound of the exhaust is mostly gone. This is true of outside of the car at idle as well, it feels like the physical sensation of pressure from the exhaust is diminished. Most of the drone has moved to 1,500 rpm now, which I don't mind at all since I never stay there. I chose to install the damper just behind the center carrier bearing, the midpoint of the exhaust, because it seemed that was where most of the vibration would be. I thought I would have to experiment with placement but the results are so good I think I will just leave it there.

 

 

The damper is Toyota Part No. 17581-31010 which I installed with these Flat Band Exhaust Clamps from Amazon. I still have a damper I didn't use that I might install at the Y-pipe.

Edited August 9, 2020 by Enlight

Also, all these recordings are with the panels in my trunk area removed, no spare tire, etc. as I sound deaden the area. I'm looking forward to seeing the improvement after I re-install that trim.

Interesting, have you tried mounting the mass dampers in different locations along the exhaust and re-running the spectrum analyzer?

 

Another thing to note is that it just changed the resonant frequency, not the amplitude. In recording #1, peak amplitude goes from just over .20 to just over .25. And in recording #2, it goes from just over .2 to midway between .2 and .25. But the units of measurement is in (g), which I'm not familiar with, I would expect dB, so I don't know what a (g) is. Regardless, in both examples, it's more. In the case of recording #2, it drops the resonant frequency to less than 10hz. That's below what is regarded as the threshold for human hearing, and would probably register as a shake/vibration, not a pitch. So that one makes sense - it moves the drone out of audible range. For recording #1, it moves the resonant frequency to a higher pitch. So it's still there, but higher. This one would fall as a judgment call as to which is preferred. Or rather, which is less annoying.

 

Disclaimer: this is just what I can guess by reading the charts posted. The cool thing about audio is that measured results are usually only part of the story. For a lot of things, it's easy to hear what sounds better, or more preferred. It can be unanimous among 100 people who hear it, but the charted signature would tell otherwise. So this is awesome! I love seeing this kind of experimentation going on. We can all benefit from it because we all drive Subarus!

I didn't have enough time today to try different positions which was my original intention, but throughout the process I also realized that the damper only had a few places it could go if it wasn't going to be the lowest hanging part under the car. The first place was very close to the exhaust hanger attaching to the transmission, which is up towards the downpipe. Because it was so close to the hanger, my conjecture was that it wouldn't have its maximum impact since that part of the exhaust was already affixed. The next part of the exhaust farther towards the mufflers was right behind the center driveshaft bearing which is what I chose.

 

 

You are correct. I'm no sound engineer but I understand that anything below 20hz is considered sub-sonic. Also, the data I provided was quite noisy, even with the two before and afters. There was quite a bit of traffic here today so I was unable to run more samples at 80mph/3,000rpm (I have a STI 6-speed), which is what I wanted to target because that's where the drone is on my long drives. Also, the app I use only records 5 seconds at a time, and I believe it was designed to measure the frequency of stationary equipment (i.e. more controlled environments). I also had to take into consideration road surfaces which were pretty varied for my samples. I did not include samples from rough surfaces that I drove on. I believe that introduced a lot of noise into my samples. The (g) scale confused me as well and I had to do some Googling on it.

 

 

For the time being, I don't think I will change locations of the damper due to space constraints and my satisfaction with its results. I may add the second damper down the line. Here is the thread from Club Lexus where I got the idea from (via

). If you are bothered by the drone from your car, this experiment is so cheap (less than $75) that it's worth a shot. It sounds hyperbolic, but the car sounds better now than before, even with all the trim in the trunk area that is still removed. Edited August 9, 2020 by Enlight

That's so cool. What exhaust and DP are you running?

I'm running the STI quad-tip exhaust which is a big increase over the stock mufflers, Invidia downpipe, and AVO mid + Y pipes. The car previously belonged to atwood then bsax11 on this forum before it got to me. Atwood performed almost all of the modifications so I, unfortunately, can't report on the impact of these mods in isolation, but I believe the AVO pipes are quite loud too, even with the resonator they came with.

The reason I ask is that I had to sell 2 exhausts because they were too loud for me in my wagon. Invidia Q300 which I got to a bearable level with muffler tip inserts but could not fix some drone, and Greddy sedan version which I liked visually.

 

 

I have CNT catted DP but stock mid and mufflers after that. I'd like something just a hair more beefy so your discovery can be a solution down the road.

For such a small investment I think it's worth a shot. Upon driving the other day, the loudness of my exhaust is definitely still there, but the drone/resonance that was reverberating in the car before was much improved, if that helps your decision at all.

I just bought a mass damper yesterday to see if it can tame the drone of my nameless peformance catback.

 

I downloaded a spectrum analyzer to test a before and after once I get the damper.

 

On a side note, the dampers are kind of hard to buy online. I ended up buying ones from partsouq as it was cheapest even with the international shipping.

Link?

Link?

https://partsouq.com/en/search/all?q=1758150090

I just bought a mass damper yesterday to see if it can tame the drone of my nameless peformance catback.

 

I downloaded a spectrum analyzer to test a before and after once I get the damper.

 

On a side note, the dampers are kind of hard to buy online. I ended up buying ones from partsouq as it was cheapest even with the international shipping.

 

Please share your observations!

 

On that note, I made another responsible financial decision today. HKS made a "Super Turbo Exhaust" for the BP5 that came with a J-Pipe. I don't like the blue-tipped mufflers that it came with, but then I came upon an UpGarage listing where someone had swapped out those cans for the ES Silent Hi-Powers. I ordered them through GetJpn and will have to find a way to get the system from CA to NY after they arrive via container - I'm hoping to piggyback a uShip.

 

Road trip anyone?

I made another responsible financial decision today.

 

 

This forum is like AA meetings, except you get thanked when you make responsible financial decisions.

Please share your observations!

 

On that note, I made another responsible financial decision today. HKS made a "Super Turbo Exhaust" for the BP5 that came with a J-Pipe. I don't like the blue-tipped mufflers that it came with, but then I came upon an UpGarage listing where someone had swapped out those cans for the ES Silent Hi-Powers. I ordered them through GetJpn and will have to find a way to get the system from CA to NY after they arrive via container - I'm hoping to piggyback a uShip.

 

Road trip anyone?

 

I'll drive to CA and test them back to TN for you to let you know whether or not you would really want them in NY.

Been thinking a lot about this... Still a few years too early.

I want one too.

Installed the Recaro Style XL and managed to dig up an old post on how to disable the airbag light. I also received my HKS ES Premium catback. I decided to keep my STi quadtips and I bought this mainly just for the mid-pipe w/ Helmholtz resonator. This improvement has been much more dramatic than the tuned mass dampers for cabin drone - I love the way the car sounds now. Brought her over to RPM Motorsports to get an alignment with fresh new Bridgestone QuietTracks. The car is the most dialed-in it's ever been. Ready for the 48 Hours of Tri-state ride.

Nice!! Yeah, I'm a believer in the Helmholtz resonators.