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Old 03-05-2019, 02:34 PM   #1901
jamal
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The rear multi-link suspension gains much more camber with compression than the front strut.

1/2" of lowering isn't much but the rear camber is still going to be on the high side, like -2.

Even at stock height I think LCAs are a good idea to make sure things are even and lets you put it closer to -1.5 instead of over -2. Also means you can have favorable front to rear balance without excessive front (and rear) camber.
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Old 03-06-2019, 06:21 AM   #1902
Eagleye15
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Quote:
Originally Posted by jamal View Post
The rear multi-link suspension gains much more camber with compression than the front strut.

1/2" of lowering isn't much but the rear camber is still going to be on the high side, like -2.

Even at stock height I think LCAs are a good idea to make sure things are even and lets you put it closer to -1.5 instead of over -2. Also means you can have favorable front to rear balance without excessive front (and rear) camber.
Makes sense. No matter which direction I go I will pick up some adjustable rear control arms. Thanks.
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Old 03-07-2019, 06:51 PM   #1903
Economatic
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I'm not sure if this has been covered but I'm curious if anyone has tried running the RCE Bilsteins with the stock springs from a 2018-19 STi? How would the car handle and what would the ride quality be like?

Just some background, I bought the RCE Bilsteins and yellows back in November knowing exactly what I was getting myself into because I had the same setup on my '09 WRX. Fast forward 3 months and I ended up ordering a new "fun" car so the STi is getting demoted to daily driver duty and I'll be using it in the winter for skiing and it'll see gravel roads in the summer. So the full 20mm drop from the yellows is a bit too low and the ride is too rough for how I'll be using the car. I had planned to go back to the stock dampers and springs but maybe keeping the Bilsteins will be a good compromise?

Hopefully someone has tried this or RaceComp will chime in here...or I can email Myles.

Last edited by Economatic; 03-07-2019 at 07:59 PM. Reason: Correction
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Old 03-07-2019, 07:35 PM   #1904
Norm Peterson
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Quote:
Originally Posted by Economatic View Post
I had planned to go back to the stock dampers and springs but maybe keeping the Bilsteins will be a good compromise?

Hopefully someone has tried this or RaceComp will chime in here...or can email Myles.
This might help a little - while it's a different situation I ran RaceComp Bilsteins on the 2010 LGT that we used to have, with the OE springs (the Bils were actually valved for somewhat firmer spring rates). Aside from somewhat firmer response to road unevenness - I'm not talking about broken pavement here - they worked out quite nicely. I do suspect that there was some initial seal friction/stiction, as ride quality over those same unevennesses did gradually improve.

Relative to the OE LGT dampers, the % critical damping was clearly moved toward best road handling performance, assuming that the OE dampers were oriented more toward best ride (duh). As a rough guideline, best performance seems to occur at two to three times the critical damping where you get the best ride. More about this can be found in 'Race Car Vehicle Dynamics' or Dixon's Shock Absorber Handbook.

I might have Myles' email address somewhere - no promises though as it's been several years.


Norm
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Old 03-07-2019, 08:08 PM   #1905
Economatic
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Quote:
Originally Posted by Norm Peterson View Post
This might help a little - while it's a different situation I ran RaceComp Bilsteins on the 2010 LGT that we used to have, with the OE springs (the Bils were actually valved for somewhat firmer spring rates). Aside from somewhat firmer response to road unevenness - I'm not talking about broken pavement here - they worked out quite nicely. I do suspect that there was some initial seal friction/stiction, as ride quality over those same unevennesses did gradually improve.

Relative to the OE LGT dampers, the % critical damping was clearly moved toward best road handling performance, assuming that the OE dampers were oriented more toward best ride (duh). As a rough guideline, best performance seems to occur at two to three times the critical damping where you get the best ride. More about this can be found in 'Race Car Vehicle Dynamics' or Dixon's Shock Absorber Handbook.

I might have Myles' email address somewhere - no promises though as it's been several years.


Norm
Great info--exactly what I was looking for. And I'll have to look up those documents/handbooks you suggested. Sounds like some good reading material for the novice that I am. Thanks!

I noticed I had a typo in my origin post. I meant to say that I could email Myles if we don't hear from RaceComp on the forum. I figured I'd post the question here for public knowledge.
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Old 03-08-2019, 08:38 AM   #1906
RaceComp Engineering
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Quote:
Originally Posted by Economatic View Post
I'm not sure if this has been covered but I'm curious if anyone has tried running the RCE Bilsteins with the stock springs from a 2018-19 STi? How would the car handle and what would the ride quality be like?

Just some background, I bought the RCE Bilsteins and yellows back in November knowing exactly what I was getting myself into because I had the same setup on my '09 WRX. Fast forward 3 months and I ended up ordering a new "fun" car so the STi is getting demoted to daily driver duty and I'll be using it in the winter for skiing and it'll see gravel roads in the summer. So the full 20mm drop from the yellows is a bit too low and the ride is too rough for how I'll be using the car. I had planned to go back to the stock dampers and springs but maybe keeping the Bilsteins will be a good compromise?

Hopefully someone has tried this or RaceComp will chime in here...or I can email Myles.
Not Myles, but...yes! you can definitely use the GTWORX Bilsteins with stock springs. The OEM dampers are overdamped in front and underdamped in the rear. We focused on balancing that out to help support our Yellows spring rate but it also improves how the car feels on OEM springs (which for your uses, will be a great fit). I think you'll really like the combo on the roads you drive on.

- Andrew
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Old 03-08-2019, 08:41 AM   #1907
Norm Peterson
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Quote:
Originally Posted by Economatic View Post
Great info--exactly what I was looking for. And I'll have to look up those documents/handbooks you suggested. Sounds like some good reading material for the novice that I am. Thanks!
Just so you know, those are hardcover college-level texts and are priced a bit above the softcover automotive books you find in consumer bookstores. You'll probably have to go through the SAE bookstore unless you can find them through Amazon, e-bay, or Craigslist.


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Old 03-10-2019, 06:47 AM   #1908
WRX_Silveira
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I am looking for a little help. looking to upgrade the suspension of my 17 WRX (daily) for autocross and spirited canyon drives. My problem is that when looking at coilovers i seeming have hundreds of options for different spring rates and I have absolutely no idea what i need or what i am even really looking at. Any input is appreciated.

Current set up is:
whiteline front and read swaybars with endlinks
Cosmis R1 (18x9.5 +35) wrapped in Nexen N-FERA SU1 (255/35zr18)
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Old 03-10-2019, 08:50 AM   #1909
Boggie1688
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Quote:
Originally Posted by WRX_Silveira View Post
I am looking for a little help. looking to upgrade the suspension of my 17 WRX (daily) for autocross and spirited canyon drives. My problem is that when looking at coilovers i seeming have hundreds of options for different spring rates and I have absolutely no idea what i need or what i am even really looking at. Any input is appreciated.

Current set up is:
whiteline front and read swaybars with endlinks
Cosmis R1 (18x9.5 +35) wrapped in Nexen N-FERA SU1 (255/35zr18)
That is a tough question to answer. Springs work in conjunction with valving. Not many manufacturers making their dynos available. Even if they did, you'd need to have experience riding in a car with a few different valving settings and know what the graphs were before you could make any real comparison and understand what you like.

The valving should have a range of spring rates they work with. You should really try to talk to the manufacturer and ask what range that is. Then take the lowest end of the setting and spring rate and see if they can give you an idea of how that rides to stock.
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Old 03-10-2019, 11:56 AM   #1910
RaceComp Engineering
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ASK ABOUT NEW RCE
SWAY BARS FOR STI

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Quote:
Originally Posted by WRX_Silveira View Post
I am looking for a little help. looking to upgrade the suspension of my 17 WRX (daily) for autocross and spirited canyon drives. My problem is that when looking at coilovers i seeming have hundreds of options for different spring rates and I have absolutely no idea what i need or what i am even really looking at. Any input is appreciated.

Current set up is:
whiteline front and read swaybars with endlinks
Cosmis R1 (18x9.5 +35) wrapped in Nexen N-FERA SU1 (255/35zr18)
Where are you located?

There's a big range in coilover options now from budget, mid-range, "Clubsport", and motorsports type coilovers. And also coilovers that sort of bridge the gap between two classes.

We recently released our RCE SS1 coilovers, which are a damping adjustable (1 way) damper made by KW to our specs. They are our option somewhere between entry level and mid-range. We're really happy with the valving and specifically the adjuster on them...the range of adjustment is very usable. Some coilovers really only have a few settings where they actually work well (i.e. the stiff end is insanely stiff and the soft end is mushy floaty crap). There are plenty of other options out there, including other options from us at RCE...this is just a new one that we are excited about for this platform.

If you're nearby, Myles in the shop would be happy to give you a ride in his 2018 STI. I have them on my BRZ.

- Andrew
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Old 03-10-2019, 12:14 PM   #1911
jamal
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I think he mostly means the spring rates that come on different sets are really variable.

I'd suggest something on the firmer side and with rear spring rates equal or slightly higher than the fronts. RCE has a few things that should work.
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Old 03-17-2019, 10:02 PM   #1912
danividi
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Rims ?
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Old 03-17-2019, 10:04 PM   #1913
danividi
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Quote:
Originally Posted by x SLYC x View Post

Concave enough for you? These are 18x9.5 +38. This pic is before installing RCE Yellows, but they fit is still great with the drop. No issues, no rubbing.
Rims ??
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