body roll

I notice body roll, as all of you have when you first bought your legacy... Now whats a good way to reduce that without really lowering the car? There probably isnt a whole lot I am able to do, but I figured it was worth a shot to ask!

How about an anti-roll bar.......AKA sway bar.

thats what i was figuring! man i feel like a dumbass... time to go wallow in my stupidity!

No, this is what this forum is for...

 

Others would have called you a silly n00b but not us.

 

 

Try searching for JDM 20mm sway bars, Cobb Sway bars, and ion springs, or Tein springs, or anything else in the suspension section.

 

replacing the rear sway bar with a JDM 20mm anit-sway and some iON springs changed the car dramatically.

 

It's not the canyon carver my old Honda was, but it was a drastic improvement.

 

If you want to get more serious suspension, PM XenonK. He is a serious suspension guru.

I personally like the thicker bars. I just took my coilover out for the winter so no all i have is perrin 25mm bars F+R. The car still drives very flat. If you get big sways and a good set of dampers but keep the stock springs, you will retain ride height but all handleing aspects of the car will improve.

I would like to retain the independent suspension and upgrade the shocks instead... this gives a better overall performance than just the bar alone.

Keep in mind that the normally aspirated Legacy models use a different front sway bar than the turbo LGT models. Rallitek sells a 22mm F/19 mm R sway bar kit for the non-turbo Legacies:

 

http://rallitek.com/raswbarkit.html

I would like to retain the independent suspension and upgrade the shocks instead... this gives a better overall performance than just the bar alone.

 

I'm keeping stock bars and going with JDM Spec B struts and springs, and the above is one of the reasons.

 

Stock ride height, firmer ride, OEM long-term durability, and not only reduces roll but the dive and squat as well.

 

As for coilovers, Megan Racing has Outback coilovers that firms up the ride and retains the stock ride height (and can go higher if desired).

Part #13

Suspension!!

This part was originally written by Unclemat. you can find a full discussion of this topin here: http://legacygt.com/forums/showthread.php?t=61108

 

Quote:

Originally Posted by Unclemat

JDM OEM suspension FAQ

 

What is OEM suspension on JDM BP/BL Legacy?

 

JDM Legacy GT, GT SpecB, 3.0R SpecB use Bilstein struts and shocks. The fronts are inverted monotube struts. Other trims use lesser KYB shocks, similar to what USDM 2.5i and GT have. The difference in handling is amazing; the car on Bilsteins drives infinitely better than stock. In fact the car is more comfortable, too - while impact hitting a road imperfection can be felt more, the dampening so much better and quick so it goes away instantly, while stock will float and bounce much longer.

 

What is the difference between JDM GT Bilsteins and JDM SpecB Bilsteins?

 

JDM GT Bilsteins try to balance ride comfort and performance. They are much sportier and provide far more controlled ride than stock USDM GT dampeners (KYB). JDM SpecB Bilsteins are geared more towards performance at some sacrifice in ride comfort.

 

What the heck are these confusing revisions?

 

Revision is actually a misnomer. The lettered "revisions" refer to model years in JDM. A is MY2004, B is MY2005, C is MY2006 and so on. Indeed, the suspension actually was revised several times that resulted in differences in dampening and springs. Generally each subsequent revision got softer due to the complaints that these cars ride too stiff.

 

Note, there was no "original revision" or "revisionless" Bilsteins. Some posts, including the "Part numbers" thread in turbo section contain incorrect information.

 

JDM GT Rev.A

 

Original GT setup. Reportedly great balance of performance and ride comfort. I briefly rode in a car with this setup and was surprised that it actually felt closer (but more compliant) to JDM SpecB Rev.B I had at the time than to JDM GT Rev.C I had earlier. Everyone who has this setup seems to praise it, especially with Pinks.

 

Part numbers: 20310AG060 (front right), 20310AG070 (front left), 20365AG040 (rear)

 

JDM GT Rev.B

 

This one is bit of a mystery. Does not really feel softer than JDM GT Rev.A. Interestingly rear shocks are the same as on JDM SpecB Rev.B, front struts are different. I just drove a car with these on Pinks and indeed the setup seemed more complaint than JDM SpecB Rev.B, but the difference is not big. Note, there is an old post quoting someone from Bilstein Japan saying this setup is for SpecB and tuned for 18 inch wheels - that is incorrect, I verified this against JDM parts database.

 

Part numbers: 20310AG140 (front right), 20310AG150 (front left), 20365AG120 (rear)

 

JDM GT Rev.C

 

This is the current JDM GT and JDM 3.0R setup, present on Rev.D cars as well. Also used on 2006-2007 USDM SpecB (not sure about 2008 yet). These are noticeably softer than any other revisions. Give nice and controlled and oscillation free ride, but they are more on the comfort than performance side. There were complaints that these do not handle stiffer springs (Pinks) very well and feel bit underdampened. I can believe this as in certain high speed situations these did not feel as secure as other revisions.

 

Part numbers: 20310AG400 (front right), 20310AG410 (front left), 20365AG260 (rear)

 

JDM SpecB Rev.A

 

The original SpecB setup, stiffest of the bunch. I rode in a car with supposedly this revision (not 100% sure, not confirmed by part numbers) - it felt marginally stiffer than SpecB Rev.B. Opinions about this setup range from "great ride" to "too stiff for daily driver". I guess this is very subjective plus it depends on the road conditions, wheel size, tires, etc.

 

Part numbers: 20310AG100 (front right), 20310AG110 (front left), 20365AG050 (rear)

 

JDM SpecB Rev.B

 

Supposedly softer than Rev.A. I had it on my car with Pinks for few months and liked it very much. Excellent performance, yet still great ride. However, can be too harsh on really bad roads if paired with stiff tires like RE070.

 

Part numbers: 20310AG180 (front right), 20310AG190 (front left), 20365AG120 (rear)

 

JDM SpecB Rev.C

 

This is the current JDM 2.0 SpecB and JDM 3.0R SpecB, present on Rev.D cars. Bit less aggressive than Rev.B, yet still excellent handling and great ride. This is my favorite Bilstein setup so far for a street car - I think they really got this one "perfect".

 

Part numbers: 20310AG420 (front right), 20310AG430 (front left), 20365AG270 (rear)

 

Are Bilsteins the same for sedan and wagon?

 

Yes there are no differences in struts/shocks between sedan and wagon.

 

Are springs the same for sedan and wagon?

 

No, rear springs on wagons are a little bit longer to compensate for extra weight. Note the extra weight is minimal (60 lbs. for non-limited wagon vs. non-limited sedan).

 

How USDM SpecB Bilsteins compare to JDM Bilsteins?

 

USDM SpecB Bilsteins are identical to JDM GT Rev.C Bilsteins, see above.

 

What are the JDM tophats?

 

JDM cars use different front top hats (mounts). The USDM top hats cannot be used on JDM OEM Bilsteins (or other struts like Ohlins, Tokicos, Bilsteis HDs) - the USDM top hat has taller bearing and the threaded portion of the strut rod is too short and will not allow for safe installation. Pictures that compare JDM and USDM top hats are located here.

 

By the way, JDM top hats are beefier, the bearing in them is huge compared to USDM one. Thet are much stiffer, help steering response and contribute and to the "road feel" - there is much less play in the top hat. USDM top hat is very rubbery and clearly designed for comfy ride.

 

The JDM and USDM names are customary - JDM top hats refer to top hats used on Bilsteins, including Bilsteins on USDM Legacy SpecB. USDM top hats are used on some JDM cars, not sure which but are used on some Outbacks. Note, interestingly AusDM 2.0i or 2.5i cars seem to use JDM top hats on KYB struts.

 

Do JDM tophats raise the front of the car?

 

I compared these top hats side by side and they seem to locate bottom of the bearing at the same height with respect to the chassis, so the top hat should not affect ride height. This is moot question since the top hats are not interchangeable, with the exception of KW Variant 2 coilovers.

 

I installed Bilsteins and my rear sits lower wrt front than I would like! Why?

 

There might be few things which contribute to this. First, our cars from the factory seem to "sit back" - the rear wheel gap is smaller than front, this gets accentuated when the car is lowered. Second reason might be use of AT specific front springs on MT car. This however should be negated a bit since USDM cars should be a bit heavier in front - 2.5L vs, 2.0L and cast iron manifolds vs. tubular steel headers.

 

But, frankly, I don't really know why....

 

My advice for sedans is to use wagon springs and/or using two spring seats. The latter seems to be the only option for wagons. Another way is to use springs that by design drop front more than rear - like Wangans, Provas or TN Guts. All rare JDM only items unfortunately.

 

Can I use JDM springs on USDM stock dampeners?

 

Yes. However they will drop the car more in front compared to JDM suspension. The reason is that lower spring perch on the front struts is actually located lower compared to Bilsteins. Ascetically this is good as it results in more even stance, however I do not believe USDM struts/shocks can handle stiffer lowering springs.

 

Can I use USDM stock springs on Bilsteins?

 

No. USDM stock springs are longer and while probably you could cram them on Bilstein, the car won't ride or look good. Other USDM specific springs like USDM-specific Ions on Cobbs might fit but again would be seriously mismatched.

 

What are Pinks?

 

Pinks are lowering springs designed and sold by STI branch of Subaru. Compared to stock JDM cars lower the car all around 15mm.

 

Pinks are not designed for stock struts and result in crappy ride. If mated to stokers they lower more like 25mm.

 

More info about Pinks to come.

 

I want to install Bilsteins, what parts do I need?

 

For the front you need JDM top hats, corresponding dust caps (seals) and front spring upper perch/seats. Some people used stock USDM GT front perch/seat, but since they look bit different and have different part number I recommend using the Bilstein specific one. Also, the dust boots are different in front. For the rear you can use the stock top hat and spring seat.

 

Of course you also need some sort of JDM GT/SpecB specific springs like STI Pinks, Swifts, R-SR, Wangans, Teins or Provas, etc.

 

Part numbers (available from US dealers):

 

20320AG000 - front top hat (strut mount), 2 needed -

20326AG000 - front top hat dust cap (dust seal), 2 needed

20323AG000 - front spring seat/perch, 2 needed.

20322AG010 - front dust boots, 2 needed.

 

Any tips on the install?

 

Not really. Make sure to properly position front seats/perches - the drain holes need to be oriented outside. Do not use stock dome washer/spacer between spring seat and top hat. Other than that universal precautions apply, do not over torque stuff, top hats bolts and piston rod can be easily broken.

 

Links to useful install threads: here and here.

 

Where to get OEM Bilsteins?

 

JDM GT Rev.C / USDM SpecB Bilsteins can be bought from any US dealer. JDM only revisions need to be imported from Japan.

 

What about aftermarket Bilstein HDs?

 

Bit of a mystery here. They look pretty much the same as OEM Bilsteins and also share monotube inverted construction. Originally a Bilstein dealer claimed they have less travel than OEMs in front (108mm vs. 130mm) making them not well suited for lowering springs. Recent findings are that they have the same travel as OEM Bilsteins, plus few members are using them successfully with Pinks so it seems these concerns are unfounded.

 

They supposedly ride bit stiffer then OEM USDM Bilsteins. Dealers claim 20% stiffer. Can't say, never rode in a car equipped with them.

 

The bigger mystery is the difference in price - OEM Bilsteins cost more than $1200 new from the dealer (in the US or Japan), while HDs seem to cost around $500. I don't know where the difference comes from, hard to explain it only by OEM markup. My guess is the proprietary dampening and stricter quality control.

 

The following part was written by SUBE555. The complete thread and discussion can be found here: http://legacygt.com/forums/showthread.php?t=571

 

 

Quote:

Originally Posted by SUBE555

Suspension is an area that really allows an individual to tailor the vehicle to their driving needs and desires. Some of the most common types of suspension components are listed below along with what they do and what kind of impact they make on handling or if they are basically just for aestetics.

 

Strut Tower Bars

http://homepage.mac.com/futureofx/.Pictures/LSTIHOST/2-6.jpg

While being pertinent to many vehicles to increase chassis rigidity, older models in particular, strut tower bars (which span from the top of one strut tower to the opposing tower, mounted over the coil-over assembly) have become less useful in the latest Impreza models as well as even the BE/BH (2000-2004) Legacy models due to the absolute strength and rigidity present in the newest chassis. The new Legacy should further improve over the last making STB’s virtually useless in sedan models unless you want the look, and functional basically in just the rear location for wagon models.

 

Sway Bars, Mounts & Endlinks

Sway bars are probably one of the best handling modifications available to reduce body roll and understeer (the tendency for the nose to keep going straight while you want to turn.) Choosing an appropriate sway bar size (generally 19-22mm without upgraded front bars, or up to 24mm with upgraded front bars) will make a very noticeable handling difference, and considered by many to be one stage one-type modifications. Some things that must be taken into consideration though is with bars set to 20mm and higher, the stock mounts may break, thus aftermarket companies are starting to ship hardened mounts with their bars to alleviate this problem. Otherwise, they can be found separately. Additionally, endlinks may want to be upgraded as well, particularly with going to a higher set sway bar diameter, as the increased stress could make these more prone to breaking and their effectiveness becomes reduced. (At press time I am unaware if the USDM models have upgraded to new steel units I have seen pictures of which may negate the need for upgraded end links. I am only aware of this on the Legacy models however.)

 

Springs, Struts & Coil-Overs

http://homepage.mac.com/futureofx/.Pictures/LSTIHOST/RST2100.jpg

The chassis is really held up by two main components off the axles, springs and struts (also known as shocks.) The springs suspend the body of the car and everything attached to it, while the struts ensure the tires stay in contact with the road with a high-pressure gas. There are many different options with this setup, but it is highly recommended that the struts and springs be matched for optimal performance, safety, and to minimize chance of damage to the suspension equipment. This setup can come in the form of a ‘coil-over’ which is essentially a spring and strut in a unit, many of these aftermarket units are adjustable by spring rates (the higher the weight, the harder they will ride) and stiffness of the struts (known as dampening rates.) More widely used (particularly by OEMs) are a combination of springs and struts.

 

There is a growing line of sport springs available for the Legacy models while finding applicable struts is hit or miss for many model years. Most springs lower the chassis by about 1” giving it a slightly more level stance while increased spring rates give the car a more supple ride. There are many solutions available for the Impreza chassis currently, and we may see at least a couple of the better solutions available for the Legacy chassis within the next year.

 

As good as springs and struts are at reducing body roll and increasing agility, they work best when coupled with at least a heavier rear sway bar or matched set (designed for the perfect handling balance- not the same size as match may be interpreted as) of front and rear sway bars.

 

Control Arms, Bushings & Links

http://homepage.mac.com/futureofx/.Pictures/LSTIHOST/2-2.jpghttp://homepage.mac.com/futureofx/.Pictures/LSTIHOST/thumbRST2000.jpg

To keep the suspension of your vehicle as responsive, quick acting, and rigid as possible, upgraded bushings, rear lateral links, and aluminum front control arms are one of the best kept secrets in the book. Subaru uses softer bushing and heavier steel suspension components to keep cost and NVH down on their normal street cars. What many don’t know is that for many of the road going cars, FHI produced STi versions of these components that are more rigid, lighter, and have better bushings to reduce unsprung weight, help your car respond faster with better feedback, and track better with increased alignment precision. Sometimes it’s the little things that really count.

 

A good discussion and explanation of the Multi-Link Rear suspension found on the BL/BP gneration Legacy's can be found here LINK

 

Alignment

http://homepage.mac.com/futureofx/.Pictures/LSTIHOST/thumbRST2030.jpg

If you are planning on racing your Legacy or the alignment shop doesn’t meet your specs, you may want to check out aftermarket Strut Top Mounts and/or alignment bolt kits which allow you to tailor your alignment to your specific needs (like race days) and can help provide a more sturdy alignment with even greater range of settings.

 

 

long but very useful.

i scanned it real quick, but that seems very helpful! i'll be sure to read it!

Keep in mind that the normally aspirated Legacy models use a different front sway bar than the turbo LGT models. Rallitek sells a 22mm F/19 mm R sway bar kit for the non-turbo Legacies:

 

http://rallitek.com/raswbarkit.html

 

CRAP, for real?

 

I just ordered a set of Perrin sway bars... does that mean the front sway won't fit on my 2.5i?

OK to summarize, let's see if I got this: for the current US Spec B setup on a legacy sedan you need:

 

mount parts (available from US dealers):

 

20320AG000 - front top hat (strut mount), 2 needed -

20326AG000 - front top hat dust cap (dust seal), 2 needed

20323AG000 - front spring seat/perch, 2 needed.

20322AG010 - front dust boots, 2 needed.

 

JDM GT Rev.C / USDM SpecB Bilsteins can be bought from any US dealer.

 

STI Pinks from same US dealer

 

that should do it? Any idea about rough cost?

 

Answered by Fred Bean - all except the springs:

http://www.fredbeansparts.com/servle...gacy-GT/Detail