apexjapan Posted November 21, 2006 Share Posted November 21, 2006 Ch-ch-ch-changes. The rolling R&D studio that is my car has gotten a few new bits of metal and urethane bolted in, and what a difference they make! Much more than I had thought they would. To outline what state of suspension my car is already in, it's currently riding on a set of HKS Hypermax coilovers and has been lowered about 3-4 cm. The rear stabilizer bar had already been upgraded to an AVO 20mm solid adjustable stabilizer bar, which provides a nice improvement in roll resistance over the hollow tube JDM OEM 20mm rear stabilizer bar. I was lucky to have gotten one of the first year Legacy GT's in Japan, as they came with a 20mm hollow bar in the rear as standard. Later years the bars became smaller! The stabilzer endlinks have also been updated front and rear with AVO adjustable endlinks. If anybody is curious about the level of testing I do when it comes to suspension, I've snapped a few endlinks in two during the initial testing. Once it was in the mountains around Tokyo, around midnight. It was at the rear, so was not too dangerous, I just adjusted my driving style and kept on going! The AVO rear stabilizer mount brackets. http://www.avoturboworld.com/images/stories/avostories/bp_sus_kit01/stabi_mount001.jpg What has been added to the mix of suspension now is two different bits. At the rear, the stabilizer bar mounts were upgraded with the new AVO stabilizer bar rear mount brackets. It bolts over the standard mount and to the rear t-mount, adding in a whole lot more metal for the rear bars to bolt up to. At first I was skeptical that it would do much, but that was because I never paid much attention to how thin and flexible those rear mounts are. I quickly changed my view after driving the car with the bracket mounts in! I could feel the difference immediately, as it felt as if a larger rear stabilizer bar had been fitted. That was not the only benefit, as it turns out. Some high speed corners showed that it was far more stable at the rear, with no wibble-wobbles at the rear to sap my confidence. Mounted on the car http://www.avoturboworld.com/images/stories/avostories/bp_sus_kit01/stabi_mount008.jpg So you could say I was pretty happy so far. But we were not stopping there. Next up was a test of the new CAB system for the front suspension. The Caster Adjustment Bushing system does just that, increases the caster up front slightly, and also replaces the big, squishy tennis ball that the front suspension pivots on with a harder polyurethane bushing. I knew that increasing the caster would help both turn-in and straight line stability, but the worry was towards NVH - noise and vibration harshness levels. Which is why I was testing it. The CAB in all its glory http://www.avoturboworld.com/images/stories/avostories/bp_sus_kit01/bp_cab_kit_001.jpg I suppose I should not have worried at all. While there was a slight increase in feedback, it's not harsh at all. I actually enjoy the increased feedback from the steering, as it is much easier to feel what is going on at the front now, and it's not painful at all. The steering effort is a little higher now, at least at the initial tug to the steering wheel. That is due to the stiffer bushing, which has less give to it. There is also quite a bit more straight-line stability, which is quite welcome to me. Even when properly aligned, the car felt nervous in a straight line, and I felt as if I had to pay constant attention. Now it feels much more solid and steady when cruising down the expressway, even at high speeds. Crosswinds appear to affect it less than before, and it resists tramlining better. Once the corners appear that the most dramatic changes are felt. Despite the car having not been aligned properly, it feels much better at every turn of the wheel. It appears that, just as the bracket mounts removed wobble in the rear, the new polyurethane bushings and increase caster have removed wobble at the front. Cornering is much, much flatter in the front, even at low speeds, and especially at high speeds. The car is quite neutral now with just a touch of understeer at speed. It is dialed in perfectly for going very, very quick. Along with the increase in feedback, it is now much easier to dive in and feel my way through the corner, as I can tell what's going on with total confidence. I took my usual route through the Shutoko expressway to test it out (think Tokyo Highway Battle). That pretty much sealed the deal for me once I whizzed through my favorite corners a good 10-15km/h faster with less tire scrub from the front, and a heck of a lot more confidence mid-corner. After much thought about this, I believe I know what has happened. Subaru designed the front bushings to be quite soft, especially that big main one. This reduced NVH levels quite a bit, but it also introduced a lot of flex and play into the system. This is why they specified such a large stabilizer bar - 21mm - in the front as standard equipment. That is actually fairly large for a factory car that is as light as the Legacy. And the very first version of the Legacy GT came with a nice rear bar as well - a hollow 20mm rear stabilizer bar. The only problem with this setup is that it was dependent upon a fairly aggressive suspension setup and rubber. Without those two components, the car got a bit tail-happy with the 20mm rear bar, so later models had a smaller rear bar as standard equipment. How it looks on the car http://www.avoturboworld.com/images/stories/avostories/bp_sus_kit01/bp_cab_kit_004.jpg With the current setup, the car is set up very well. Now that the front bushing isn't moving around so much, the standard 21mm stabilizer is more than up to the task of keeping the front of the car nailed down. The additional caster does not hurt at all in that regard as well. And with the solid 20mm adustable rear bar and bracket mount upgrade, the rear is also nailed to the ground. Overall, I'm pretty stoked. I can't wait till the next time attack at Tsukuba, as it is now quite a bit faster through the corners, even with the dampers set to full soft. Even on the street it is much more fun to drive now, and feels more the proper sports sedan. I cannot wait to see what comes up next! Cheers, Paul Hansen http://www.avoturboworld.com Link to comment Share on other sites More sharing options...
Th3Franz Posted November 21, 2006 Share Posted November 21, 2006 Sweet. I'll be calling you guys up come spring time. -Franz The end of a Legacy http://www.youtube.com/th3franz Link to comment Share on other sites More sharing options...
MIKEBRAVO Posted November 21, 2006 Share Posted November 21, 2006 How much? If you can afford College, you probably don't need to go. Link to comment Share on other sites More sharing options...
jaspert Posted November 21, 2006 Share Posted November 21, 2006 Great review. How much for the bracket and the Control arm bushes? Link to comment Share on other sites More sharing options...
Brack Posted November 21, 2006 Share Posted November 21, 2006 Where to buy? Link to comment Share on other sites More sharing options...
itsme Posted November 21, 2006 Share Posted November 21, 2006 Yes, how much for bracket? Racer X FMIC for '05-'09 LGTs, '08+ WRX and '10+ LGT,'14+ FXT, and '15+ WRX TMIC Racerxengineering.com Link to comment Share on other sites More sharing options...
PGT Posted November 21, 2006 Share Posted November 21, 2006 more importantly, when did you put the aluminum control arms in (stock?)?? US cars aren't so lucky as to get them stock. Link to comment Share on other sites More sharing options...
apexjapan Posted November 22, 2006 Author Share Posted November 22, 2006 Stock! And yes, I checked on the pricing for those arms here, about $350-370usd... each. :o :o I'm not sure I am supposed to be posting prices here, so I will put something up in the Vendor Announcements later today. I need to input them into the online store first. Cheers, Paul Hansen http://www.avoturboworld.com Link to comment Share on other sites More sharing options...
LittleBlueGT Posted November 22, 2006 Share Posted November 22, 2006 DO the bushings change where the front wheel sits? Does it sit further forward in the wheelwell now? Full tune of 68HTA, KSTech 73 MAF, Racer X FMIC and ID1000s................by the DataLog Mafia!!! Link to comment Share on other sites More sharing options...
apexjapan Posted November 22, 2006 Author Share Posted November 22, 2006 Yes, they do sit further forward, though not by a whole lot. It hasn't affected turn or caused rubbing issues. I have like a +41 offset on those wheels as well, which is literally the absolute limit! Cheers, Paul Hansen http://www.avoturboworld.com Link to comment Share on other sites More sharing options...
Gmachine Posted November 22, 2006 Share Posted November 22, 2006 Thank you ,thank you........two more pieces to my puzzle. I needed confirmation that bushings were out there to fit the alum. control arms. Will / are these bushings available as offset or standard fitments? Sign me up:icon_bigg Dave Link to comment Share on other sites More sharing options...
apexjapan Posted November 22, 2006 Author Share Posted November 22, 2006 Yes! Ah, I mean, yes to both offset and standard, though I honestly suggest the caster offset that I tried - it's really improves things that much. Cheers, Paul Hansen http://www.avoturboworld.com Link to comment Share on other sites More sharing options...
Gmachine Posted November 22, 2006 Share Posted November 22, 2006 I have a set of MSI camber plates which offer a setting for additional caster. Question, the offset bushings move the rear of the control arm inward or outward,depending on orientation when pressed in. Does this have any negative effect on the front LCA bushing? Such as binding,premature wear? Link to comment Share on other sites More sharing options...
outahere Posted November 22, 2006 Share Posted November 22, 2006 .....I suppose I should not have worried at all. While there was a slight increase in feedback, it's not harsh at all. I actually enjoy the increased feedback from the steering, as it is much easier to feel what is going on at the front now, and it's not painful at all. The steering effort is a little higher now, at least at the initial tug to the steering wheel. That is due to the stiffer bushing, which has less give to it. There is also quite a bit more straight-line stability, which is quite welcome to me. Even when properly aligned, the car felt nervous in a straight line, and I felt as if I had to pay constant attention. Now it feels much more solid and steady when cruising down the expressway, even at high speeds. Crosswinds appear to affect it less than before, and it resists tramlining better..............Cheers, Paul Hansen http://www.avoturboworld.com I share your feelings about the stock suspension Legacy being nervous in a straight line, and having to pay constant attention on the freeway. How much has your caster increased? What in your opinion accounts for most of the improvement in straight line stability, the stiffer bushing or the increase in caster? Link to comment Share on other sites More sharing options...
j255c Posted November 22, 2006 Share Posted November 22, 2006 +1 especially recently, dont know if its the cold weather or wind up here in mass.. but my car does not feel confident at all in a straight line on the highway, also drifts a lot to both sides. Rather annoying. 06 TB EVO IX SE stock turbo monster subaru hater Link to comment Share on other sites More sharing options...
apexjapan Posted November 22, 2006 Author Share Posted November 22, 2006 The additional caster is the main reason for the increased straight line stability. Though I imagine that the bushings themselves help cut down on minor movements as well, and may be part of it. Cheers, Paul Hansen http://www.avoturboworld.com Link to comment Share on other sites More sharing options...
tangcla Posted October 13, 2007 Share Posted October 13, 2007 Bit of a thread dig, sorry... I have the STi aluminium lower control arms already, do the caster bush make a huge difference over standard? Also, was there any increase in NVH with the bushes? Link to comment Share on other sites More sharing options...
rmcferon Posted October 13, 2007 Share Posted October 13, 2007 Also, was there any increase in NVH with the bushes? Some people have reported an increase. I didn't notice any increase in NVH and more importantly my Wife didn't notice any either. Link to comment Share on other sites More sharing options...
Ross Wilson Posted June 15, 2008 Share Posted June 15, 2008 Stubai Mounts are back in Stock. Thnaks Ross Wilson AVO Turboword Link to comment Share on other sites More sharing options...
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