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Discussion Starter #1 (Edited)
I installed Ohlins Road and Track Coilovers, as well as Super Pro Adjustable Sway bars back around December of last year. I have the max lowering, which is only about 1" and at the time, I also installed Whiteline Center Bump/Roll kit. The car was corner balanced and aligned with -2.0 Camber up front, -1.5 out back and zero toe all around.

I know chassis has some upgraded stiffening in the 2018+ model STI, and the factory struts were different, as well. I also know that Ohlins uses the same PN/application for 2007-present cars. This is one thing that kind of annoys me, but they had very high praise. Unfortunately, I couldn't really get any feedback from 2018+ owners at the time I purchased them. I know the chassis is relatively the same for many years. but is it possible that this kit's dampening is no loner optimal for the newer cars?

Ever since I've had the suspension set up, as described above, the car has been scary unpredictable at higher speeds (above 90mph). Initiating turn it unsettles the car and makes me uncomfortable. Hitting the smallest of bumps in a corner at speed causes the car to start wallowing, or loose traction of all 4 wheels. It seems to be that the high speed valving circuit is not ideal for my car. It drives like a car that has had factory springs chopped. Super stiff and bouncy. It does not quickly recover from bumps or imperfections in the road, but rather just goes into a fast bouncing motion. The factory suspension was much more predictable and controlled, although it was a bit softer.

I'm currently running all 4 coil overs at 8 clicks out from full firm. Ohlins suggests starting at 10 clicks out. Going softer/slower on adjustability just makes the car mushier, but not more controlled. I haven't tried going stiffer/faster because it's already a bit spine busting.

Now, another thing to mention here, is that I am slightly suspect of my alignment setup. The very first alignment I had on this car made an amazing step towards stability. I added front camber bolts, and rear lower controls arms. I asked the shop to max out and match front negative camber (they got to around -1.5) and I left the rest up to them based on my driving style. I live in the mountains and drive fairly aggressive most of the time, regardless of what car/truck I'm driving. But after I installed all the new suspension components, I took it to another shop for corner balance and alignment. I only chose to do this because a coworker is a trackday junky and has a go to shop who does a lot of his work. They specialize in trackday prep, upgrades and repairs. I'm seriously thinking about going back to my known good shop, who only specializes in alignments and suspension work to have them go through it again. But, alignment has very little to do with wallowing and harsh bouncy dampening.

I actually regret selling off my factory struts, as I would be willing to swap it all back, to verify it's better. Really not trying to spread any hate over any of the components I chose, but would like to hear back from any of you who have the later model 18+ cars and chose Ohlins.

Thanks
Erik
 

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Discussion Starter #2
I did just go back and find the paperwork from the 1st alignment and maybe this is a clue as to why the car felt so stable? My memory was inaccurate...

F Camber -2.0, -2.0
F Toe +1/6, +1/16

Rear Camber -1.5, -1.5
R Toe +1/16, +1/16

Maybe the tow in made a huge difference in how the car drove? I only made about 6-7,000 miles so hard to say what the long term tire wear would have looked like... Now I have RE-71R's and they are not cheap, nor do they last very long...
 

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Erik,
Sorry to hear you're having troubles. We sell TONS of these, install and corner balance them and have been for over a decade. We have custom valving packages and I run them on my current Porsche and STI race cars as well as my last STI race car. I spent 2 seasons, over 65 days on track, developing our Track Package. You're running off the shelf valving, which is under sprung in the rear for max performance. However, this is the first complaint I've ever heard. Besides my personal Ohlins cars I've test driven dozens of cars we've installed these on and they work fantastic.

What sway bars are you running and on what setting?

What were the corner weights and cross %?

How much pre-load are you running on the springs?

We typically run 0 toe and -2 front and rear for street cars. Alignment can have a huge affect on stability and turn in feel but as you pointed out, it's not going to make the car wallow.

I have a stock setup I can send you if you cover shipping.
 

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Discussion Starter #4
Joshua,
I am curious to know many 18+ cars you've set up or driven with these coil overs. I was also told by Geoff at Cygnus that he does not like Ohlins because of the split spring rates, and this also dictated his choice for my swaybar setup below. I just assumed it made sense to have mismatched spring rates because I doubt the car is is anywhere near 50/50 distribution, plus you just never hear any complaints about these. Although, just today, I found a post at another forum from someone else who has an '18 and preferred the stock struts over the Ohlins.

Swaybars - Super Pro 26mm Front, set to softest position
Adjustable End Links - neutral
Super Pro 24mm Rear, set to middle position
Rear Swaybar Stiffening Bracket
Fixed End Links

Corner Balancing Data w/passenger: Cross % LF/RR = 50.2 RF/LR = 49.8

Left Front Total Right Front
1137 3671 1040


Left Rear Right Rear
788 706

Preload - Literally just enough to make sure the springs are captured at full extension. I rechecked preload after ~3,000 miles of driving.

Is the stock setup from a 2018 or newer car? I might consider this to try for shits and giggles.

For now, I think I'm going to play around with Ohlins and set the front to 12 clicks out and the rear to 10 clicks out to compensate for mismatched spring rates. Maybe I will do a little DOE on the settings to see if I can improve the feel. I'm assuming that if I wanted to change up spring rates, I'd also have to be re-valved to match the spring rate. I feel a little foolish because I actually gave away the suspension because I hate having shit gathering up in my garage. Luckily though, I did give them away to someone who works at a major tire chain, so he was able to get me a really good price on the RE71R's.
 

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I'd guess 8 or 9. More than a few for sure.

Square springs aren't the correct approach either. The motion ratio in the rear dictates a higher rear rate for any serious track use. What that means for the aggressive street use is up to you. 500/600 is our standard Track Package. We have a Street Package coming out this summer, oriented more for comfort but with proper bias still. Ohlins will say the stock valving can accommodate up the 20% changes in rate. Even if true you are left not having any adjustment. We revalve all of our packages for the springs leaving our customers with a full range of adjustment.

We've never used super pros so can't comment on them.

Those fixed end links are hosing your corner balance but I'm sure you know that already.

The OTS Ohlins are valved for the springs they come with so I wouldn't really call it mismatched springs or suggest compensating with upping the dampening. If you really think it's under sprung then it'll just be over damped to boot.

I think the set we have is from a 16 or 17 but I'm sure an 18+ will come in within a week or 2, who knows if they'll bin the stock suspension though...

Check out Sport Cup 2s next time around. Lighter and more grip.
 

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Discussion Starter #7
Those fixed end links are hosing your corner balance but I'm sure you know that already.
The fixed links are on the rear. Front links are adjustable, but I could have them setup wrong. I’ve read about preloading, but it’s not clear to me what that really means... I can set them to any length within the range, but it doesn’t preload the bar. The bar just rotates to the longer or shorter position. Maybe I should have my suspension shop look at that, as well.
 

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The fixed links are on the rear. Front links are adjustable, but I could have them setup wrong. I’ve read about preloading, but it’s not clear to me what that really means... I can set them to any length within the range, but it doesn’t preload the bar. The bar just rotates to the longer or shorter position. Maybe I should have my suspension shop look at that, as well.
You need adjustable links all the way around. If the side to side height is different, which is almost always will be the sway bar will have a preload without adjustable links.
 

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Discussion Starter #10
@Ebnash Apologies for the tangent but which suspension shop do you get your car corner balanced at?
In this case, my car was corner balanced at Elite Performance in Burlingame, which is basically an import speed shop That recommended by a friend. i don’t plan to go back.

My preferred shop for alignment and suspension related work is Custom Alignment in a Mountain View. This is who did my 1st alignment prior to Coilovers. I will be going back to them to have car realigned and perhaps corner balanced. I will also be bringing a set of adjustable rear endlinks with me and have them set up my sway bars.
 

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Discussion Starter #11
So I've been digging around the internet (I know a dangerous thing sometimes) and then looking at my car for comparisons. A couple new interesting points...

1. Both of my front endlinks are not perpendicular to the ground/bar. They are both angled in a way that makes it seem that the front sway bar is too wide. I know I've read of some links, like kartboys that requires spacers to get straight up and down, but my problem is the opposite. I need a negative spacer ;-) Attached pictures of both front endlinks.

59560
59559


2. I also noticed the inner lip of my wheel (only the left front) has been rubbing on something. I went back and looked at my factory wheels, and only one of them had this same wear pattern. Since I I only had the factory wheels with the new coilovers for a couple thousand miles and never rotated tires during that time, the only deduction is that there is an interference problem on my Left Front Suspension. I only notice the rim rub because I held my phone under the car to get a picture of the swaybar endlink this morinng in the work parking lot. I have not had time to remove the wheel to look for the contact point. But I can tell you that when I reach under the car there is almost no space between the lower spring pad/adjustment collar and the tire. And as the suspension compresses, this would bring the rim closer to the coil over. This also might explain why I hear a rubber squeak only from the front end when I go over a speed bump and have the windows down. WTF. I popped the hood and verified that the top hats are on the correct side (L on the drivers side and R on the passenger side), but maybe I fucked up when I mounted the top hats to the coil overs themselves. Below, I zoomed in on the portion of the picture that shows the wear on the inner rim lip, and it's clearly an up/down pattern, not circular... Shit Not matter how you figure it, has to be related to the coil overs...

59561
 

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The sway bar link angularity doesn't make any difference, ideally it would be straight but it's not a problem.

You front strut is moving together with the wheel. Unless your alignment shop cranked ton of negative camber in at the knuckle and dialed it back out on the camber plate these shouldn't be anywhere near touching. And it would be touching all the time.

We run these same wheels and Ohlins on our race car and they clear by a mile. No rubbing, no issues.
 

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Discussion Starter #13
The sway bar link angularity doesn't make any difference, ideally it would be straight but it's not a problem.

You front strut is moving together with the wheel. Unless your alignment shop cranked ton of negative camber in at the knuckle and dialed it back out on the camber plate these shouldn't be anywhere near touching. And it would be touching all the time.

We run these same wheels and Ohlins on our race car and they clear by a mile. No rubbing, no issues.
The point about knuckle angle seems very valid. Before I installed Coil Overs, I had already installed camber bolts to achieve the -2.0 in front. When I installed my coilovers, I marked strut mounting bolt to make sure they went back to the same position after installation. So I'm sure the shop who did my last alignment and corner balance, probably did not touch those. Thanks Josh, this is a very good observation. Looks like I need a new alignment, for sure.

What do you do for setting the camber eccentric bolts in the strut mounts? I'm assuming you would at least want the angle's to be relatively matched since this is a static setting? I want to be able to give very specific instructions to my alignment shop before I make an appointment.

Thanks again.

I realize that the wheel and tire move with the lower half of the strut, but as the suspension compresses the wheel and tire move upward, while the spring and top hat remain relatively static in angle. I'm still hopeful that the knuckle angle will resolve the contact. The sound I hear when I make contact with a speed bump makes matches perfectly with tire to spring squeak...
 

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On these cars we even the camber at the knuckle and make the rest of the changes at the camber plate. Typically we'll shoot for -2 in the center of the camber plates travel and sweep the curve so the customer knows what all the way in and all the way out are camber wise. Just need to balance this with inner and outer clearance. When we run 295 tires more positive settings are required at the knuckle then the camber gets added back in up top.

The point about knuckle angle seems very valid. Before I installed Coil Overs, I had already installed camber bolts to achieve the -2.0 in front. When I installed my coilovers, I marked strut mounting bolt to make sure they went back to the same position after installation. So I'm sure the shop who did my last alignment and corner balance, probably did not touch those. Thanks Josh, this is a very good observation. Looks like I need a new alignment, for sure.

What do you do for setting the camber eccentric bolts in the strut mounts? I'm assuming you would at least want the angle's to be relatively matched since this is a static setting? I want to be able to give very specific instructions to my alignment shop before I make an appointment.

Thanks again.

I realize that the wheel and tire move with the lower half of the strut, but as the suspension compresses the wheel and tire move upward, while the spring and top hat remain relatively static in angle. I'm still hopeful that the knuckle angle will resolve the contact. The sound I hear when I make contact with a speed bump makes matches perfectly with tire to spring squeak...
 

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Discussion Starter #15
On these cars we even the camber at the knuckle and make the rest of the changes at the camber plate. Typically we'll shoot for -2 in the center of the camber plates travel and sweep the curve so the customer knows what all the way in and all the way out are camber wise. Just need to balance this with inner and outer clearance. When we run 295 tires more positive settings are required at the knuckle then the camber gets added back in up top.
Thanks again Joshua. Really wish I was closer to your shop. You have been a wealth of knowledge and information.
 

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I did just go back and find the paperwork from the 1st alignment and maybe this is a clue as to why the car felt so stable? My memory was inaccurate...

F Camber -2.0, -2.0
F Toe +1/6, +1/16

Rear Camber -1.5, -1.5
R Toe +1/16, +1/16

Maybe the tow in made a huge difference in how the car drove? I only made about 6-7,000 miles so hard to say what the long term tire wear would have looked like... Now I have RE-71R's and they are not cheap, nor do they last very long...
If I'm reading what you've posted here correctly, there is toe out in both the front and the rear? If that's the case then @[email protected] nailed it, you want the car either at zero toe in the rear, for handling, or slightly toed in at the rear for stability.
Think of toe out in the rear as making the inside tires being more eager to turn in during cornering while the outside tires are more eager to swing away from the inside of the turn.
If you can imagine going through a corner with all four tires like that you get the picture as to why it causes the instability. Great for autocross where your speeds typically don't go over 60. Great for highly skilled drivers who can use the additional instability to steer the car. Not so great for mortals like us who feel the car starting to slide unexpectedly during maneuvers where it shouldn't.
 

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Discussion Starter #17
If I'm reading what you've posted here correctly, there is toe out in both the front and the rear? If that's the case then @[email protected] nailed it, you want the car either at zero toe in the rear, for handling, or slightly toed in at the rear for stability.
Think of toe out in the rear as making the inside tires being more eager to turn in during cornering while the outside tires are more eager to swing away from the inside of the turn.
If you can imagine going through a corner with all four tires like that you get the picture as to why it causes the instability. Great for autocross where your speeds typically don't go over 60. Great for highly skilled drivers who can use the additional instability to steer the car. Not so great for mortals like us who feel the car starting to slide unexpectedly during maneuvers where it shouldn't.
No, I’ve never had toe out. My 1st alignment before Coilovers was 1/16 toe in on all 4 wheels with -2 F camber and -1.5 R camber. Latest alignment with Coilovers and corner balance is zero toe all around and same camber numbers.
 

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Ok, my apologies. I thought I was reading toe out at all four corners and that would generate what you were describing.
 

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is the spring preload at the suggested rate? also going softer than the recommended based on my experience causes what you are describing...I have to keep mine softer due to migraines and thus the lack of capability at higher speeds..
 

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Discussion Starter #20
Ohlins manual does not suggest a preload rate, that I know of. They only suggest that you set preload so that the spring is captured at full extension.
 
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