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2004 Forester XT MT
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Discussion Starter #1 (Edited)
Test: 04 Wagon Struts w/ USDM STi Pink Wagon Springs (update 2/15/05)

Going to test out the stock 04 wagon suspension. Then I'll install the wagon specific STi springs and see how it drives.

The swaps will be spaced out between autoX events so I can get a good idea of the performance changes. I've already seen what Moose can do with the Helix DNA's and have something for which to shoot.

Suspension Predictions:
Stock Wagon vs. JDM FSTi
-Lower CG -> Reduction in body roll
-Softer Tophats -> Decreased NVH
-Increased spring rate -> Reduction in body roll
-Change in damping -> Pass the Coffee Drinking Test (JDM FSTi currently doesn't pass)


Wagon w/ STi
-Stiffer spring rate -> Reduction in body roll but less compliant ride (might not pass Coffee Drinking Test)
-Lower CG (slight) -> n/a

*Any change in ride height can change the weight distribution and thus change the steering characteristics for each setup. I dont have any way to weigh Moose. :D

When it's all done, I'll sell the suspension(s) that I won't use. (hint, hint)

Update February 4, 2006
Part 1: Getting a BASELINE

Going to Auto-X on the FSTi suspension tomorrow. I haven't had the chance to wring out this suspension/setup at an Auto-X.

Suspension/Handling Mods:
JDM FSTi struts and springs
COBB front and rear bars (full stiff)
Perrin solid end links
Cusco rear strut tower brace
STi lateral links with pillow ball bushings
Whiteline Steering rack bushings

Alignment Specs:
Front:
  • Camber: -1.0
  • Caster: 3.2
  • Toe: 0.00
Rear:
  • Camber: -1.0
  • Toe: -0.16 (total)
On the street:
It feels like I have plenty of control through the corners. I can steer with the throttle by inducing under/oversteer.
The steering rack bushings were the final piece of the puzzle it seems. The car can hold a line through turns very well.

Update February 5, 2006
The FSTi suspension performed extremely well at the Auto-X yesterday. Even for a car running at this height I think it can be very competitive in the hands of a good driver. The Moose acutally looked better than one of the new Mustang GT's in stock trim. Less body roll, dive, and squat. But with my driving skills, I couldn't get the most out of this setup. In my class, I was slower than the guys with Hoosiers but faster than at least one! MY CAR CAN GO OVER SPEED BUMPS, TOO!:p

(If I was one of those nationally ranked drivers I could blame the stock brakes...:cool: )

FSTi @ the Auto-X:
Great turn-in.
Easy to balance through the turns.
Ran the slaloms well even with the height disadvantage.
Much less nose dive and squat than stock.

Update February 15, 2006
Part 2: Stock Wagon Suspension

Well, I decided to skip this part and proceed directly to the STi Pinks. I figured that the ride quality would be nice but not stiff enough for the twisties.

Part 3: STi Pinks (Wagon) on Wagon Struts

So the springs and struts are on without a hitch. I'm using H&R camber bolts in the rear and stock eccentric bolts in the front.

For now it looks like getting camber to -1 degree in the back will be okay; although, I don't think it will make it to 0 degrees. I'm shooting for -1.5 degrees in the front and should also be okay. Once I get Moose to the alignment shop, I'll ask them to check the possible range of camber in the front and rear.

STi Pinks/Wagon Struts on the street:
I am extremely happy with the ride quality. The STi Pinks are a perfect match for the wagon struts. Even with the stiffer spring rates, it is smoother than the FSTi setup and will pass the coffee test. Once the alignment is done, I'll test out my favorite stretch of road. I expect great results since the body roll is significantly less during normal lane changes and turns on city streets. Less squat and dive are other noticeable improvements.

Update February 19, 2006

Answer to the million dollar question...
"What kind of camber can you get out of the wagon suspension?":

Front Camber: -0.8 to -2.0 (with the stock eccentric bolt)
Rear Camber: -0.7 to -3.0 (with the H&R camber bolts)
So for most of us who lower the car for handling, the camber range is pretty good. Tire wear will be good, even with camber at -1.0 at all for corners. (It's usually the toe setting that eats up tires.)

Moose's Alignment Specs:
Front:
  • Camber: -2.0
  • Caster: 3.5
  • Toe: 0.00
Rear:
  • Camber: -1.5
  • Toe: 0.00
I opted for a little more negative camber to help through the turns. Somehow caster increased by 0.3 with the wagon suspension; this is a good thing.

More impressions of the wagon/sti springs on the street:
The wagon strut mounts are definitely softer than the ones on JDM FSTi struts.
  • Why this is good for ride quality: smaller road imperfections don't make it into the cabin.
  • Why this is bad for autocrossing: they flex in a turn and can increase the time for the suspension to settle during transitions.
Moose is lower now than when I had the DNA's; I scraped the front mudlfaps going over a big speed bump too fast.


Update March 1, 2006


I'm sorry it took so long but here are the after pics.:grin:
This setup is actually lower than the tallest height on the DNA's.
The last picture show how the lateral link is actually parallel to the ground. This is the ideal angle for most sports car suspensions and seems to work well for the Moose.

Clearances:
  • Front mudflap=3-1/4"
  • Rear mudflap=4-15/16"
(front mudflap is the lowest point on the car)



Update March 5, 2006

STi Pinks/Wagon Struts at the AutoX
I was really happy today with this setup. At first, I was afraid that the struts might not be stiff enough for the transistions Moose normally sees during an autocross run. But they performed much better than expected and I think I had the fastest time among the guys in my class running street tires. This is the best compromise between a comfortable daily driver and autocross worthy performance.

Improved grip through the turn:
The car rolls a bit more initially than it would with the JDM FSTi. Then the suspension sets up and it just tracks around the turn. Overall the body roll is less, it's just a matter of when I get the roll. Maybe the Wagon Pinks are wound such that the progressive rate has more travel? (rear sway was in the middle postion)

Better braking:
This is the best I've seen the stock brakes perform. Maybe it's due to more initial weight transfer caused by the softly damped struts. Eventhough it was a fast course today and there was a lot of gravel, I didn't kick in the ABS at all. (I don't think the ABS likes higher damping...anyone?)
 

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'09 STI
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Northwest Tan said:
-Softer Tophats -> Decreased NVH

-Change in damping -> Pass the Coffee Drinking Test (JDM FSTi currently doesn't pass)

Wagon w/ STi
-Stiffer spring rate -> Reduction in body roll but less compliant ride (might not pass Coffee Drinking Test)
-Lower CG (slight) -> n/a
(hint, hint)
Are the JDM forester tops similar to Group N? If so then there will be a significant reduction in NVH.

I'm surprised the JDM Forester struts are too stiff to drink coffee. I have 7K springs with Group Ns but I drink a couple of shots out of a to go lid and have no problems.

You may find that the WRX/STi springs are oversprung on the WRX struts making for a bouncy ride.
 

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2004 Forester XT MT
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Discussion Starter #3
NahdaDamdyke said:
Are the JDM forester tops similar to Group N? If so then there will be a significant reduction in NVH.

I'm surprised the JDM Forester struts are too stiff to drink coffee. I have 7K springs with Group Ns but I drink a couple of shots out of a to go lid and have no problems.

You may find that the STi springs are oversprung on the WRX struts making for a bouncy ride.
:cool: Not sure if they are Group N but the with the increase NVH I'm guessing the JDM FSTi strut tops are stiffer than the USDM stock.

:D Coffee drinking is like trying to see the whole picture through a picket fence. You only get a few short chances at a time. The ride quality is good but I mainly drink my coffee at stop lights...Being overdamped has it's advantages and disadvantages.

:cool: There have been mixed reviews about STi springs on stock struts. Some of the wagon guys enjoy their STi Pinks on their stock struts. A bouncy ride is one of the things I'm tring to avoid.

I'd like to clear up what I mean by overdamped:
  • A damped spring system is technically considered overdamped if it can't properly return to it's equilibrium nor does it pass through the equilibrium. The JDM FSTi suspension is actually closer to being critically damped and not technically overdamped.
  • My use of the term overdamped refers more to the ride comfort. In most cases, a car that returns to equilibrium quicker will not be as comfortable as one that gets there gradually. (think Integra Type-R vs. Towncar)

(STX legal eccentric control arm bushings are in the works, too. But I'll wait until I get the struts/springs sorted before do that part.)
 

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2012 camry se 6AT
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2,809 Posts
Northwest Tan said:
Going to test out the stock 04 wagon suspension. Then I'll install the wagon specific STi springs and see how it drives...

Wagon w/ STi
-Stiffer spring rate -> Reduction in body roll but less compliant ride (might not pass Coffee Drinking Test)
-Lower CG (slight) -> n/a
Northwest Tan, that should be a really good street setup. That was that route I wanted to go, 04-05 Wagon struts on 04 Wagon STi "soft" pinks, but I had no luck for months looking for a used set of 04-05 Wagon takeoffs. The wagon "soft" pinks should lower the WRX takeoffs one inch. I will be very interested in your review.
 

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'09 STI
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Northwest Tan said:
:cool: There have been mixed reviews about STi springs on stock struts. Some of the wagon guys enjoy their STi Pinks on their stock struts. A bouncy ride is one of the things I'm tring to avoid.
I misread your original post. I thought you were putting on WRX/STi springs. The WRX pinks you are trying are probably a better match to the WRX struts.

Being overdamped and undersprung can also give a bouncy ride ala the WRX/STi stock springs. The springs can't overcome the dampening and results in the tire not following or absorbing bumps.
 

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2004 Forester XT MT
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Discussion Starter #8
Part 1: Getting a BASELINE

Going to Auto-X on the FSTi suspension tomorrow. I haven't had the chance to wring out this suspension/setup at an Auto-X.

Suspension/Handling Mods:
JDM FSTi struts and springs
COBB front and rear bars (full stiff)
Perrin solid end links
Cusco rear strut tower brace
STi lateral links with pillow ball bushings
Whiteline Steering rack bushings

Alignment Specs:
Front:
  • Camber: -1.0
  • Caster: 3.2
  • Toe: 0.00
Rear:
  • Camber: -1.0
  • Toe: -0.16 (total)

On the street:
It feels like I have plenty of control through the corners. I can steer with the throttle by inducing under/oversteer.
The steering rack bushings were the final piece of the puzzle it seems. The car can hold a line through turns very well.
 
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Any reason you're going for the WRX wagon struts over WRX sedan struts?
 

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2006 RX8
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andyroo said:
Any reason you're going for the WRX wagon struts over WRX sedan struts?
I really didn't think the narrow-body WRX Wagon struts were a great choice for the Forester due to the camber issues caused by the differences in the strut mounting bolt-hole location. I think ride-height wise and perhaps spring rate-wise the WRX wagon springs would make sense, but other than that I thought the WRX sedan and wagon strut damping were pretty similar?

Here's a link to some info on the Wagon vs sedan differences :
http://forums.nasioc.com/forums/showthread.php?t=857305
 
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So wagon springs on sedan struts would be the best overall solution in terms of WRX takeoffs...


I think im gonna be doing 05 WRX sedan struts with STi takeoff springs, which are almost exactly the same rate and drop as the USDM Pink STi springs that are available from dealers. They aren't wagon specific, but I don't think my rear will sag much since the springs are so stiff. I wonder how low I'll be and how much camber I'll have though.


- andrew


EDIT: I'll be very interested to see how much camber Northwest Tan gets out of the wagon struts.
 

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2006 RX8
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andyroo said:
So wagon springs on sedan struts would be the best overall solution in terms of WRX takeoffs...


I think im gonna be doing 05 WRX sedan struts with STi takeoff springs, which are almost exactly the same rate and drop as the USDM Pink STi springs that are available from dealers. They aren't wagon specific, but I don't think my rear will sag much since the springs are so stiff. I wonder how low I'll be and how much camber I'll have though.


- andrew


EDIT: I'll be very interested to see how much camber Northwest Tan gets out of the wagon struts.
All of the reading and info you get off of these forums can be informative and helpful, but like you I will be interested to see if the narrow body WRX wagon struts really are much different than the WRX sedan. Northwest Tan should be able to confirm this for us soon!
 
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N10S said:
All of the reading and info you get off of these forums can be informative and helpful, but like you I will be interested to see if the narrow body WRX wagon struts really are much different than the WRX sedan. Northwest Tan should be able to confirm this for us soon!
I have STi springs sitting here in my living room...so i hope he hurries up! ;)


- Andrew
 

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2004 Forester XT MT
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Discussion Starter #14
andyroo said:
Any reason you're going for the WRX wagon struts over WRX sedan struts?
It was a no brainer. I came across an awesome deal on the wagon take-offs and then another great deal on brand new STi wagon specific pinks. (Great deals always seem to show up when you aren't looking.)

I don't think I'll have any problem getting the amount of camber needed with the wagon struts. The stock front eccentric bolts should allow me dial up to -1.5 degrees of camber. For the rear suspension I'll be using the H&R camber bolts to dial in the necessary values.

Anything greater than -2.0 degrees of camber is excessive. As the camber increases, the contact patch in a straight line decreases resulting in less grip during acceleration and braking. Most of the time people go more negative to compensate for loss of camber in the turns. A different method is to try to control the loss by minimizing body roll and/or increasing caster. Lowering the car and installing bigger swaybars is what I've chosen to do.

I've also found that as you increase the camber you also get more "camber thrust". This makes the car want to pull left or right on uneven surfaces. This is pretty annoying on roads that are rough or have prominent ruts.
 

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2004 Forester XT MT
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Discussion Starter #15
andyroo said:
I have STi springs sitting here in my living room...so i hope he hurries up! ;)


- Andrew
LOL bear with me! There are usually 2 Auto-X events a month. After tomorrow's event I'll throw the stock wagon suspension into the mix.
 
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Sounds good. I would definitely be happy with -1.5 degrees camber. More would be nice if I had decent tires, but I don't...at least not yet. Since I can get sedan struts, I'll probably just stick with those.

My STi takeoff springs are basically the same rates as yours...I do wonder if I'll have more butt sag then you since yours are wagon specific. I hope not, and since the rates are so stiff I don't think it will be that bad.

I'll post up my numbers when I do my install.

- andrew
 

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Thats awesome! Those alignment specs with just the JDM F-STI struts are actually pretty good! I cant wait to see what you can do with the wagon springs and struts.

BTW, I'm SUPER interested in this topic because I have a set of JDM STi Wagon struts and springs with Group N tophats sitting in the garage right now! They were going to go on my 02 wagon, but I'm in the market for a an 05 FXT, and if they work out well enough, they're going on before the engine cools!
 

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2004 FXTi
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I could be wrong but I believe using the Wagon struts on our car will give more negative camber, not less. Using sedan struts on wagons decreases camber, which is why people with wagons don't do this. Wagon struts on sedans should do the opposite. Our suspension is the same as the sedans. Let me know if I'm wrong.

Regards,
Justin Wade
2004 FXTi
 
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