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bilstein shocks or original

PostPosted: Sun Feb 06, 2011 9:23 pm
by SUM12C
Looking for opinions and help. My shocks are getting a bit old and looking at updating them.
I have the originals in it (think they are the KYB's being a MY04 GT) and have STI springs fitted and it sits at a height that I like.
From what I can gather if I go with the bilstein shock and springs combination, I would need to get new springs to fit the bilsteins to get a similar height I have now and I wont be able to use the STI springs I currently have in the car?

If that is correct I'll need to spend over $1000 to get the same height (but a better ride) and the STI springs will be sitting in the garage going to waste :(

For the cost is there another shock out there I could use to replace the origional KYB's (as good as the Billies) and keep the STI springs and end up with a similar height? I don't think there is but I wanted to make sure.

Re: bilstein shocks or original

PostPosted: Mon Feb 07, 2011 6:17 am
by garbo41610
Go the bilsteins mate. They are a great upgrade... I'm not just saying that because I have some for sale either lol. There shouldn't be any problems fitting the sti springs afterwards as far as I am aware but someone may be able to confirm.

Re: bilstein shocks or original

PostPosted: Tue Feb 08, 2011 11:54 am
by [[d a n n y]]
AKAIK
if your Sti springs are for your GT
then the bilstein springs would be the same
you can replace the billy springs with the Sti springs

Re: bilstein shocks or original

PostPosted: Tue Feb 08, 2011 3:54 pm
by Q
The springs will fit the shocks fine but the front will sit higher because of the internal pressure in the bilsteins so it won't be at the height you have now. You could get the springs reset to accomodate this though.

Re: bilstein shocks or original

PostPosted: Tue Feb 08, 2011 3:58 pm
by Robbks
Q: on that theory, the rear would also sit higher.. would it not?

Re: bilstein shocks or original

PostPosted: Tue Feb 08, 2011 4:07 pm
by SUM12C
ok, someone from subaru told me the billies were set up to allow more room to the 18" wheels (from the facelift models on). The length from the top of the shock to where the spring sits is less (so where the spring sits is higher, than the older KYB's that allowed room for the 17") and springs from the billies are similar to the STI springs from the MY04 or prefacelift models.
So I would get very little if any lowering. I thought this may be the reason why people with the MY04GT have mentioed the car sits higher when they put the billies in.
I don't really want to reset the STI springs. I might look around for a replacement for the KYB's and have a look what the early STI models were running.

Re: bilstein shocks or original

PostPosted: Tue Feb 08, 2011 7:29 pm
by garbo41610
When I put the Bilsteins into my MY05 GT, there was absolutely no difference in height. I had it measured before and after, the only difference was before they went inI think the front right was a couple of mm lower than the other 3 corners.

Re: bilstein shocks or original

PostPosted: Tue Feb 08, 2011 7:59 pm
by Q
Robbks wrote:Q: on that theory, the rear would also sit higher.. would it not?

The fronts are a much bigger unit and have alot more pressure than the rears.

Garbo, I put the oem springs from my car (MY05 GT) on the bilsteins and it turned it into an outback so they didn't stay too long!! You are the first person that I know of that hasn't had the ride height increase in the front. Did you know the history of the struts before install?

Re: bilstein shocks or original

PostPosted: Wed Feb 09, 2011 5:33 am
by garbo41610
Yeah the struts were from wheel power. They were from the GT-B to STi upgrades so they were basically brand new with just delivery kn's on them

Re: bilstein shocks or original

PostPosted: Wed Feb 09, 2011 8:09 am
by Robbks
Q wrote:
Robbks wrote:Q: on that theory, the rear would also sit higher.. would it not?

The fronts are a much bigger unit and have alot more pressure than the rears.

absolute twaddle.

size of the unit is irrelevant.
the rears are a completely different suspension principle as compared with the McPherson Struts in the front
the rears only need to worry about damping and holding the spring.
the fronts are an integral supporting (load bearing) part of the front suspension system responsible for holding the hubs to the car.
the rear has multi-link arms to do that.

I would probably agree that the billies DO give more clearance for wider wheels
this has usually been the case since the gen2 GTB's were released.
they have much more clearance from tyre to strut than the stock, GT or AUDM RX/GX struts
the spring perch is a different shape all together and may indeed be slightly higher,


so far no-one has shown before and after pics of this height difference (in this thread) to support claims one way or another

so post them up people

Re: bilstein shocks or original

PostPosted: Wed Feb 09, 2011 9:14 am
by garbo41610
Not the best quality but it is the best I can do. The pic from carsales is before the billies went in,
4529_97538202937_537217937_2718983_6023158_n.jpg
4529_97538202937_537217937_2718983_6023158_n.jpg (33.28 KiB) Viewed 8159 times


and the second pic is the ride height after the billies went in
58354_462566812937_537217937_6597793_4634030_n.jpg
58354_462566812937_537217937_6597793_4634030_n.jpg (50.17 KiB) Viewed 8159 times
.

As you can see, there is little to no difference at all.

Re: bilstein shocks or original

PostPosted: Wed Feb 09, 2011 9:45 am
by swingn
Not 100% on this, but I didn't think there was different spring models to suit standard KYB's & Bilsteins... Pretty sure they are one at the same (Can someone confirm 100%???).

I would 100% go the Bilsteins over the standard shocks in a heart beat. They are a more sporty shock & honestly feel that the Liberty's should've come standard with them. Obviously is your wanting the best, then you may need to look into coil overs etc ;)

If you did have to buy new springs, I be looking at Tein S-Techs (Phat GT is your man) or Eibachs. Either way, you can go wrong IMHO.

Re: bilstein shocks or original

PostPosted: Wed Feb 09, 2011 11:21 am
by teK--
Most aftermarket springs are not specific to the KYB or Bilstein. STI pinks though, for example have many variants depending on drivetrain combination due to different weight distribution of the chassis.

The Bilsteins will cause the car to sit at a different height then the KYB due to different spring perch height. This is reported on many LGT threads where Bilsteins are a common retrofit. This is the same regardless of the several types of Bilsteins available (JDM, HD, B8)

Check the build thread in my signature. Same springs, firstly KYB then replaced with Bilsteins. Result is that front ride height increased and the rear decreased. It is most noticeable on 17" wheels with a smaller rolling circumference. I also included height measurements.

Re: bilstein shocks or original

PostPosted: Wed Feb 09, 2011 12:38 pm
by Robbks
Right to paraphrase your thread
Stock springs and struts

Image

Stock KYB Struts with Swift Springs

Image

Bilstein struts and Swift Springs

Image
(take note of guard heights in this one. the ground drops off under the front of the car and is higher under the belly)

by looking at that the billies lower the rear 10mm too much
and the front 5-10mm not enough
this is an a 2.5 5speed MT with sunroof

need to also be aware that the 3.0 engine itself is no doubt heavier than the 2.0 and 2.5
aswell as the Auto and 6 Speed boxes being heavier (weight over the front wheels)
so there may be no issue in a 3.0R (AT or MT) or 2.5MT

Re: bilstein shocks or original

PostPosted: Wed Feb 09, 2011 12:46 pm
by teK--
Robbks wrote:need to also be aware that the 3.0 engine itself is no doubt heavier than the 2.0 and 2.5
aswell as the Auto and 6 Speed boxes being heavier (weight over the front wheels)
so there may be no issue in a 3.0R (AT or MT) or 2.5MT


That's exactly right. Those interested should look at the workshop manual and you will see that from the lightest Liberty (sedan, 2.0r, 5MT, base model), compared to 3.0RB (I think these are auto I'm not sure), is over 100kg difference at the front axle. (the actual unsprung mass is unknown though)

For a nominal spring of about 4 to 5kg/mm, this can work out to a difference in ride height difference of around 12.5mm or more at the front, given the same spring in different chassis. This is why the spring manufacturer quoted ride height drop is not reliable on our cars. The only reliable way to get cosmetic lowering is coilovers.