95turbowagon

iTrader: (17)

Is it worth getting both?

Looking at getting castor bushes for the rear of the front arms, was thinking of getting the castor/camber top mounts aswell, so if i get the top mounts is it worth still getting the castor bushes or just replace with a standard style uprated bush.

Can you get a decent amount of camber from the camber bolts on the front and just use the castor bushes to get enough castor.

Looking to use the car on track a couple of times a year, but apart from that i only use it for the odd spirited drive.

Any help is appreciated.

jura11

iTrader: (7)

What coilovers you are running?

I would rather suggest Spec C alloy arms,with those you will gain more castor


Jura

95turbowagon

iTrader: (17)

Not running coilovers, will be upgrading to sti shocks and lowering springs.

Whiteline do top mounts to give extra castor and Camber. Didn't know whether to go the route of the alk and Camber/castor mounts with it or be able to get a decent amount of camber with the camber bolts and just get the alk, for the extra castor.

jura11

iTrader: (7)

This thread will help you

https://www.scoobynet.com/suspension...l#post10605123

About the Top mounts and getting the more castor,not sure if its this possible on the OE shocks

Yes camber bolts should be good to have,ALK not sure,have this and i'm still not convinced with this kit



Jura

95turbowagon

iTrader: (17)

This is the top mounts i was looking at, it doesn't mention that there for OE but i think i'm right in presuming they are.

http://www.whiteline.com.au/product_..._number=KCA335

If they are is it worth getting the ALK or just upgrading the original bushes.

Arnie_1

The GC/GD chassis really benefit from extra caster. As Jura mentioned, the Spec C arms are a very nice upgrade with their extra caster over standard WRX or "regular" STi arms. But they are a bit pricey for sure.

The decision of whether to go with a Caster bush in the control arm or an ALK is based, for me, on two things, ease of install and whether or not you want the change in Anti geometry. Installing an ALK is fairly easy and straightforward (also has 3 durometer flavors to chose from, depending on how much NVH you can deal with), something any shade tree mechanic can do in their own driveway. The caster bush require removing both control arms and pressing out the OEM bush and pressing in the new bush. You'll most like need a shop for this. both provide about the same amount of caster gain, ca. .5 deg static and, depending on the bushing durometer, about 1 to 1.5 deg dynamic caster "gain". The change in Anti geometry is kind of a taste thing. There are definitely benefits to be had in traction improvements from "softening" of the front suspension due to the reduction in anti-lift geometry, but I've spoken to some who prefer the "platform" provided by the anti-geometry especially under braking so they just opted for the caster bushing. I personally chose the convenience of using an ALK and don't really feel any negative effects on braking or acceleration, but my butt dyno may not be as sensitive as some!

As to the top mounts, the KCA335 (Com-C) top mounts are a very nice upgrade for someone who doesn't want the harshness of a fully adjustable camber plate but still wants a mild increase in camber/caster. It also uses a stiffer Group N durometer rubber. Great for fast road and the occasional track day. With maxing out the OEM camber bolt and installing these at the max caster/camber position you'll be looking at ca. -2 to -2.3 deg camber. That's a decent amount, great for a sticky summer tire and just about enough for a semi. These are perfectly compatible with OEM struts. If anyone is looking to upgrade to an STi Group N topmount, I'd use the com-C's instead, as you get the same rubber durometer but the additional caster/camber gains.

I would recommend getting the KCA335s. I use them and like them. I personally use a "comfort" ALK because my road conditions are poor and my tolerance for NVH is low.

Good Luck!

95turbowagon

iTrader: (17)

Thanks for that arnie, i'm looking at replacing all bushes at the moment and currently have a spare set of wishbones that i'm rebushing.

Trying to get everything together and replace in one go, didn't want to buy the top mounts which give a decent gain and then buy the ALK for not much gain.

Will get the whiteline top mounts and would you advise on getting an uprated standard shape bush for the rear of the wishbone rather than the ALK, or do you recommend going for both?

Arnie_1

Cheers!

Sorry, made a mistake(been working on my peugeot too much) you don't need to replace the rear bush on the wishbone. As the rear bush is a separate aluminium housing that slides off the rear end. That's the bush you actually replace with either an ALK or caster bush. You can replace the front bush with poly if you wish, but they can be a bit harsh (NVH). For a road going car I don't really recommend them.

But definitely get the top mounts and combine with the caster bush or ALK. Combining both will give you the most gains, that's for sure. so the question ALK or rebush the the standard housing.... Personally, I'm lazy and don't like to depend on others to do my work. So I chose an ALK every time. I do also like the different bushing durometer options provided by the ALK. Since you're only using the car occasionally and not as a daily driver, you can forgo the softer comfort bushing model. The caster bush and the Sport model of ALK (KCA359) have, I believe the same durometer bush. So NVH will be about the same there. I don't think its necessary to look at the Motorsport ALK for your uses and parts combo. Sorry, still haven't answered your question really. Which to pick, which to pick...? Is money an issue? The caster bush is about half the price.

95turbowagon

iTrader: (17)

Thanks again, was thinking along the lines of rebushing the aluminium housing rather than getting the whole ALK kit as if there is not much difference in performance seems like a waste of money.

Have already got the front bush and will be buying the roll centre kit to compliment as the car will be on STI shocks with lowering springs.

Will be rebushing the rear of the car aswell, hopefully have it all done by next year so i can take it to a few track days.

Arnie_1

Sounds great! Yes, the difference in performance between the caster bush and the ALK is debatable. I'm certainly not such a track ***** that I can tell that you will gain so many tenths by using the ALK over a Caster bush. The difference is apparently there but I think for most people it may be small enough where it might not be the deciding factor on which purchase. For me, the ease of install of an ALK over rebushing the standard alu mount was always the deciding factor on recommending what to buy. I do all my installs and install many parts for friends. I don't have a press so installing a caster bush was never an option for me. So saving a hundred quid on a part may be worth it enough for you to reach for the Caster bush and apply the money savings to labor or other parts.

Rebushing the entire rear end is also very highly recommended. Makes a massive improvement on rear rotation and steering input. I always said it was akin to setting a 22mm rear bar to full stiff. That's how much a difference a rear bushing upgrade makes in terms of turn in and rotation. Once again, for ease of install I always reached for the STi 6-piece pink bits (lateral links) and the STi trailing arms (or Whiteline adjustable lateral links). Bushings are all installed and all I have do is bolt in the arms. No messing with pressing bushings out and in. STi Group N rubber bushings are a great option for the rear end if you like rubber. For poly I'd look into Whiteline or Super Pro. If you're being very picky, there is a rubber bush imbedded in the rear knuckle. The trailing arm attaches to this bush. Very worth replacing while you are in there. There are Group N or WL/SP bushings for this part too.

95turbowagon

iTrader: (17)

Thought i might aswell do the whole lot, so rather than doing it in one go i have bought all the lateral links, swing arms and front wishbones seperate and bush them as i go.

Will be painting all the parts and once that's done and they are rebushed i'll get it all fitted in one go with the alignment sorted at the same time.

Have a rear 22mm ARB on at the moment, just need to sort out a 20mm front one, have the positive steeering bushes to go on aswell also looking at the diff mount bushes and subframe chassis mount bushes.

Scoobs getting onto 11 years old and there are a few knocks and bangs when hitting bumps in the road.

Know what you mean about the hassle of getting old bushes out, the bolts are bloody stubborn as they're done to high torque and won't budge. Have got the bushes out of the trailing arms with a tool i made out of a 30mm socket, long bolt and a few washers but i've sheared off two bolts so far.

Thanks for all your help, really appreciated.

95turbowagon

iTrader: (17)

Is the bush your talking about the one on the furthest away arm?

Arnie_1

The bushing I'm talking about is actually in the rear knuckle. That empty spot at the end of the trailing arm bolts into this bush. Not 100% necessary, but its a pretty compliant bush, so why not get it done while you're at it.

95turbowagon

iTrader: (17)

I know which one you mean, was planning to get that done aswell.