Bimmerman
09-23-2011, 06:18 PM
As some of you know, I recently bought GD-fitment AST 4100 coilovers for my BK. After working with Vorshlag and AST to develop a BK-compatible rear shock internals, I then drove from CO to CA for grad school. There was a teething period on the rear shocks (wagons are...odd), since I'm Subaru wagon #2 in the country running these according to AST. Wagon rear geometry is different enough to sedans to cause an issue, which we found out and AST and Vorshlag corrected. Vorshlag's customer service is also top notch, they have gone out of their way to help me with these issues. I've got ~2000 miles on the setup now, and while the ASTs are awesome, the camber plates have impressed me more.
With all of the confusion on what the top hat patterns are on a BD/K/G, and which impreza coilover tops bolt straight on correctly, I figure I'll clear that up as well (see pictures): GC front top pattern, GD rear. Any other pattern and adjustments WILL NOT WORK CORRECTLY.
On to the main event: Why I wrote this review. Subarus have pathetic amounts of caster from the factory, and there is really no way to increase it on our cars with factory adjustments. Why do you want caster? Caster affects just about everything from a suspension point of view- dynamic camber gain/loss, steering response, self-centering, stability, and more. My 95 BK had 3 degrees of caster stock. My M3 has more than double that, and it has far better steering response, turn in, and camber curves, to name a few. You cannot have too much caster on a Subaru. It just isn't possible to get enough to have an issue.
Now, why am I talking about caster when the Vorshlag units are camber plates? Because Subarus really don't need much camber (autox excluded). Caster is far more important than adding camber for our cars.
The 95-99 Legacy is a weird hodgepodge of GC and GD suspension mounting points and oddball geometry. The front top mount pattern is GC-specific while the rear is GD specific. Believing the forum, I ordered Vorshlag's "high caster" front GC camber plates and rear GD plates. See the pictures below, they are beautiful units. The workmanship is amazing and readily apparent on these, as is the significant amount of engineering time and thought put in to how they function.
High caster steel fronts:
https://sl-i.net/FORUM/images/imported/2011/09/DSC2254L-1.jpg
GD rears (anodized aluminum)
https://sl-i.net/FORUM/images/imported/2011/09/DSC2400L-1.jpg
Many folks buying coilovers buy camber and caster adjustable plates. I've never understood this, since you want max caster all the time. As you can see from my installed pictures, you have max caster at all times and significant camber adjustment. When I had the lower camber bolt and the plate maxed out, I was getting close to -6 degrees of camber in the front. The rear is another story-- GD struts expect a wider track than a BK/BD can provide, so they add a LOT of positive camber. With the plates maxed out in the rear, I got -1 degree of camber, which is frankly plenty for these cars. With lower camber bolts or lateral links you could get much more negative, but you don't need it in 99% of applications.
Plate on the shock pre-install
https://sl-i.net/FORUM/images/imported/2011/09/fsXO2-1.jpg
https://sl-i.net/FORUM/images/imported/2011/09/xjMli-1.jpg
Look at where the shock is located in the strut tower, there is no way to add any more caster up top. Note how a GC top pattern is clearly correct for a coilover plate. GC top pattern allows camber adjustment without any significant corresponding change in caster.
https://sl-i.net/FORUM/images/imported/2011/09/KlFQa-1.jpg
GD plates in the rear allow for pure camber-only adjustment.
https://sl-i.net/FORUM/images/imported/2011/09/LD8Ln-1.jpg
Back to caster now. The Vorshlag high caster plates were advertised as adding 1 degree on a GC. I got before and after alignments to see how much the plates actually add, and was astonished. The car was aligned to 100% stock settings for camber and toe (before/after coils) since I was going to drive 1500 miles to California. The front plates added 1.8 degrees of positive (good) caster, just by bolting them on. At -2.6 camber they add 2.2 degrees of caster. Note: I do not have an anti-lift kit of any sort. This increase was purely from the plates.
Numbers are great and all, but the greatest test is behind the wheel. My car has such better steering feel that it really is hilarious the difference just these plates made. I'd highly recommend the front GC plates and rear GD plates to anyone doing a coilover install, since Vorshlag has a dizzing array of perches and bearings to fit different shock brands (Koni, Bilstein, JRZ, Moton, AST, and more) as well as spring ID and style-- they have stock perches available as well. These plates have no rubber in them yet are absolutely silent in daily operation and do not require oil or maintenance at all.
Overall, I am extremely impressed with the plates and highly highly highly recommend them for anyone wanting to improve their steering response and how their car reacts and behaves in sporty use. If there were any downsides, it is that you definitely feel the road much more (I love it) but some might not. Bumps are also harsher since the shock-plate-chassis interface has zero bushing material. It is scary fun how well this car handles now. Too bad its chassis is so noodly.
Fair disclosure, I have Vorshlag plates on my M3 also, which haven't been touched at all in 3+ years and are still silent, rock solid, and their settings have not slipped.
With all of the confusion on what the top hat patterns are on a BD/K/G, and which impreza coilover tops bolt straight on correctly, I figure I'll clear that up as well (see pictures): GC front top pattern, GD rear. Any other pattern and adjustments WILL NOT WORK CORRECTLY.
On to the main event: Why I wrote this review. Subarus have pathetic amounts of caster from the factory, and there is really no way to increase it on our cars with factory adjustments. Why do you want caster? Caster affects just about everything from a suspension point of view- dynamic camber gain/loss, steering response, self-centering, stability, and more. My 95 BK had 3 degrees of caster stock. My M3 has more than double that, and it has far better steering response, turn in, and camber curves, to name a few. You cannot have too much caster on a Subaru. It just isn't possible to get enough to have an issue.
Now, why am I talking about caster when the Vorshlag units are camber plates? Because Subarus really don't need much camber (autox excluded). Caster is far more important than adding camber for our cars.
The 95-99 Legacy is a weird hodgepodge of GC and GD suspension mounting points and oddball geometry. The front top mount pattern is GC-specific while the rear is GD specific. Believing the forum, I ordered Vorshlag's "high caster" front GC camber plates and rear GD plates. See the pictures below, they are beautiful units. The workmanship is amazing and readily apparent on these, as is the significant amount of engineering time and thought put in to how they function.
High caster steel fronts:
https://sl-i.net/FORUM/images/imported/2011/09/DSC2254L-1.jpg
GD rears (anodized aluminum)
https://sl-i.net/FORUM/images/imported/2011/09/DSC2400L-1.jpg
Many folks buying coilovers buy camber and caster adjustable plates. I've never understood this, since you want max caster all the time. As you can see from my installed pictures, you have max caster at all times and significant camber adjustment. When I had the lower camber bolt and the plate maxed out, I was getting close to -6 degrees of camber in the front. The rear is another story-- GD struts expect a wider track than a BK/BD can provide, so they add a LOT of positive camber. With the plates maxed out in the rear, I got -1 degree of camber, which is frankly plenty for these cars. With lower camber bolts or lateral links you could get much more negative, but you don't need it in 99% of applications.
Plate on the shock pre-install
https://sl-i.net/FORUM/images/imported/2011/09/fsXO2-1.jpg
https://sl-i.net/FORUM/images/imported/2011/09/xjMli-1.jpg
Look at where the shock is located in the strut tower, there is no way to add any more caster up top. Note how a GC top pattern is clearly correct for a coilover plate. GC top pattern allows camber adjustment without any significant corresponding change in caster.
https://sl-i.net/FORUM/images/imported/2011/09/KlFQa-1.jpg
GD plates in the rear allow for pure camber-only adjustment.
https://sl-i.net/FORUM/images/imported/2011/09/LD8Ln-1.jpg
Back to caster now. The Vorshlag high caster plates were advertised as adding 1 degree on a GC. I got before and after alignments to see how much the plates actually add, and was astonished. The car was aligned to 100% stock settings for camber and toe (before/after coils) since I was going to drive 1500 miles to California. The front plates added 1.8 degrees of positive (good) caster, just by bolting them on. At -2.6 camber they add 2.2 degrees of caster. Note: I do not have an anti-lift kit of any sort. This increase was purely from the plates.
Numbers are great and all, but the greatest test is behind the wheel. My car has such better steering feel that it really is hilarious the difference just these plates made. I'd highly recommend the front GC plates and rear GD plates to anyone doing a coilover install, since Vorshlag has a dizzing array of perches and bearings to fit different shock brands (Koni, Bilstein, JRZ, Moton, AST, and more) as well as spring ID and style-- they have stock perches available as well. These plates have no rubber in them yet are absolutely silent in daily operation and do not require oil or maintenance at all.
Overall, I am extremely impressed with the plates and highly highly highly recommend them for anyone wanting to improve their steering response and how their car reacts and behaves in sporty use. If there were any downsides, it is that you definitely feel the road much more (I love it) but some might not. Bumps are also harsher since the shock-plate-chassis interface has zero bushing material. It is scary fun how well this car handles now. Too bad its chassis is so noodly.
Fair disclosure, I have Vorshlag plates on my M3 also, which haven't been touched at all in 3+ years and are still silent, rock solid, and their settings have not slipped.