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      03-17-2013, 12:03 AM   #23
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Quote:
Originally Posted by M3SQRD View Post
If it uses a helper or tender spring then you basically lose the benefit of the lower height adjustment.
No. The lower adjustment allows for changing ride height without affecting shock/spring travel.
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      03-17-2013, 12:08 AM   #24
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Quote:
Originally Posted by M3SQRD
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Originally Posted by HP Autowerks View Post
You should drive them back to back and find out for yourself...I did!

Yes, this is an excellent feature as it prevents the loading and unloading of the spring to adjust ride height. The only other system with this feature is the AST 4200/4250.
With the lower front height adjuster preloaded in the steering knuckle, are you able to adjust the ride height or do you have to loosen the main steering knuckle bolt to change ride height? If you switch to a Swift setup, does the front only use a main spring? If it uses a helper or tender spring then you basically lose the benefit of the lower height adjustment.

Did you compare the RS1 and DFV on the street AND track?

What are the max spring rates the F and R e92 M3 DFV dampers capable of handling?
Would definitely be interested in street/track comparisons!
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      03-17-2013, 10:31 AM   #25
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Quote:
Originally Posted by oldmanstyle View Post
No. The lower adjustment allows for changing ride height without affecting shock/spring travel.
Yes, I understand how it works and that was not my question. You do realize the threaded lower adapter is a slip-on adapter on JRZ, TCK, MCS, and Moton. When the steering knuckle bolt is preloaded the slip-on adapter on these high-end dampers do not pull-out of the steering knuckle while in use. Consequently, this suggests the radially preload on the tapered adapter is capable of transfering the combined axial damper-spring loads (in the thousands of pounds; plus lateral shear loads because it is a strut) in shear between the adapter and damper body. I'll ask my question again, with the lower part of the threaded damper preloaded in the steering knuckle, is it possible to adjust the ride height OR do you have to untorque the large bolt on the steering knuckle to adjust height from the lower threaded portion of the damper?
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      03-17-2013, 12:58 PM   #26
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Quote:
Originally Posted by M3SQRD View Post
With the lower front height adjuster preloaded in the steering knuckle, are you able to adjust the ride height or do you have to loosen the main steering knuckle bolt to change ride height? If you switch to a Swift setup, does the front only use a main spring? If it uses a helper or tender spring then you basically lose the benefit of the lower height adjustment.

Did you compare the RS1 and DFV on the street AND track?

What are the max spring rates the F and R e92 M3 DFV dampers capable of handling?
You will have to loosen up the nut and bolt to adjust ride height. The main purpose of this set up is not to load or pre-load the spring.

Yes, just the main spring...see photo. Even with the use of a helper, the height adjustment is not affected. And here is link as well:

http://www.m3post.com/forums/showthr...ghlight=ohlins


Not on the track yet, but road feel and runs through the very rough road, mountains and canyons tell me the dampers are more precise than the RS1.

Since the R&T has such a wide range of adjustments, I am confidant that it can handle 450-500F and 800-900 rear without any issues.
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      03-17-2013, 02:39 PM   #27
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Congratulations! They look really nice.

Please get back with info after your test drives/track day which settings and heigt adjustment you used and prefered.

(I'm still awaiting confirmation for my delivery...)
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      03-18-2013, 07:45 PM   #28
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Quote:
Originally Posted by HP Autowerks View Post
You will have to loosen up the nut and bolt to adjust ride height. The main purpose of this set up is not to load or pre-load the spring.

Yes, just the main spring...see photo. Even with the use of a helper, the height adjustment is not affected. And here is link as well:

Not on the track yet, but road feel and runs through the very rough road, mountains and canyons tell me the dampers are more precise than the RS1.

Since the R&T has such a wide range of adjustments, I am confidant that it can handle 450-500F and 800-900 rear without any issues.
Loosening the steering knuckle at the track to adjust ride height without having an effect on preload sounds like a lot of work considering people already think removing fixed-bridge calipers to change pads is too time consuming!

If you are using a helper spring, not tender spring, you essentially have zero preload regardless of the upper height adjustment (easy to fully compress a helper spring to its stack height).

I'm running DFVs on my R56 Mini and RS1s on my e92 M3s (400/672 and 500/800 rates). I actually find the RS1s, at either spring rates, to be more precise as well as able to absorb large bumps much better without unsettling the balance of the car. I have both brands of dampers so I'm giving my unbiased opinion.

Max rates of 450-500 for the F dampers - seems low for a "track" damper.
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      03-18-2013, 09:23 PM   #29
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Quote:
Originally Posted by M3SQRD View Post
Loosening the steering knuckle at the track to adjust ride height without having an effect on preload sounds like a lot of work considering people already think removing fixed-bridge calipers to change pads is too time consuming!

If you are using a helper spring, not tender spring, you essentially have zero preload regardless of the upper height adjustment (easy to fully compress a helper spring to its stack height).

I'm running DFVs on my R56 Mini and RS1s on my e92 M3s (400/672 and 500/800 rates). I actually find the RS1s, at either spring rates, to be more precise as well as able to absorb large bumps much better without unsettling the balance of the car. I have both brands of dampers so I'm giving my unbiased opinion.

Max rates of 450-500 for the F dampers - seems low for a "track" damper.
I had no idea you wanted to change the ride height at track side...that will require an alignment as well, not something a weekend racer type of prep work.

I was able to drive the RS1 and Ohlins R&T back to back on the same car with the exact same spring rates, Ohlins stayed on and RS1 up for sale, enough said. RS1 is still very good, but Ohlins R&T is just a bit better on my 1M, in my opinion.

Ohlins R&T is not a "track" damper, but rather a Road and Track damper. I didn't saying 500 is max, but only said it can handle that rate without any issues.
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      03-19-2013, 04:45 PM   #30
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Quote:
Originally Posted by HP Autowerks View Post
I had no idea you wanted to change the ride height at track side...that will require an alignment as well, not something a weekend racer type of prep work.

I was able to drive the RS1 and Ohlins R&T back to back on the same car with the exact same spring rates, Ohlins stayed on and RS1 up for sale, enough said. RS1 is still very good, but Ohlins R&T is just a bit better on my 1M, in my opinion.

Ohlins R&T is not a "track" damper, but rather a Road and Track damper. I didn't saying 500 is max, but only said it can handle that rate without any issues.
So you've never adjusted ride height at the track to deal with "steady state" handling issues, like midcorner understeer or oversteer? It's not that difficult to make adjustments to compensate for changes in ride height.

Perhaps the RS1 is superior on an e9x M3

We agree on one thing - the Ohlins R&T is really just Ohlins "R"
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      03-19-2013, 06:18 PM   #31
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Quote:
Originally Posted by M3SQRD View Post
So you've never adjusted ride height at the track to deal with "steady state" handling issues, like midcorner understeer or oversteer? It's not that difficult to make adjustments to compensate for changes in ride height.

Perhaps the RS1 is superior on an e9x M3

We agree on one thing - the Ohlins R&T is really just Ohlins "R"
That takes the fun out of track days, minimum tinkering and maximum track time, all preps are done before hand.

You can add constant ID Swift main and helper and make the Ohlins R&T fully adjustable if that is what you need.
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      03-19-2013, 07:14 PM   #32
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Man, these Ohlins... beautiful. It's like industrial art.

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      03-19-2013, 10:12 PM   #33
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^^^^

Damn, I'm jelly

Post your impressions once you install them
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      03-20-2013, 05:57 AM   #34
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Quote:
Originally Posted by HP Autowerks View Post
That takes the fun out of track days, minimum tinkering and maximum track time, all preps are done before hand.

You can add constant ID Swift main and helper and make the Ohlins R&T fully adjustable if that is what you need.
You've never gone to a new track without a baseline setting? Or an old track that's been completely repaved? I can think of other reasons why you might want to adjust ride height while at the track.

On your RS1s, did you check the pressures on the adjustable internal N2 reservoirs? If the N2 pressure was at zero the damper would not feel "precise". Being able to adjust N2 internal pressure is a nice feature the Ohlins do not have.

I'm actually disappointed with the Ohlins R&T setup because it appears to be biased too far toward the "Road" (you've even stated this) and it even shows up in the spring rates - my wife runs 400/672 rates on her RS1 setup and finds it to be very comfy on the street!
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      03-20-2013, 07:34 AM   #35
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Quote:
Originally Posted by M3SQRD View Post
I'm actually disappointed with the Ohlins R&T setup because it appears to be biased too far toward the "Road" (you've even stated this) and it even shows up in the spring rates - my wife runs 400/672 rates on her RS1 setup and finds it to be very comfy on the street!
My car is a DD that will see at most 3..4 HPDEs a year. I was not happy with OEM ride when I got it. I have H&R sport lowering springs now, and while it made the car stance look good and improved roll resistance and some handling, it definitely is more harsh now and tends to side-step quite a bit over bumps mid-corner. It just feels very nervous mid-corner over uneven pavement.

I was specifically looking for a setup biased more towards road performance and comfort. I got a baby seat in the back and my wife and daughter ride with me very often. Ohlins R&T was an option and at 25% less than JRZ, I think it's a good option indeed. I've done probably close to 40+ track days on my bikes and some amateur motorcycle racing, and all my bikes had Ohlins shocks and fork internals. I have a lot of respect for Ohlins as a company and their build quality is beyond superb. I'll give them a try any day.

So, my expectations are high. I expect that on the road during my daily commute, it will feel more comfortable than stock suspension, and definitely more comfortable than H&R Sport lowering springs.

I also expect that on the road, when car is pushed, it will handle greatly and much better than OEM/H&R. Most importantly I have several very curvy roads with a lot of bumps and crests that I want this car to handle gracefully and confidence inspiring. This will be my first test as soon as these are installed and car is aligned.

I have never tracked my E90 M3, only my E46 M3, so unfortunately I will not be able to provide a good before/after comparison of OEM handling vs. Ohlins @ track. But i should be able to give you my impressions and add some videos where lap times will be indicative of how good this setup is.
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      03-20-2013, 07:40 AM   #36
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P.S. Wanted to add, while I am not expecting laser sharp race oriented setup, I obviously still expect it to handle great @ the track with shock adjustments turned up. You'll definitely hear from me if at the track I find R&T seriously lacking.
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      03-20-2013, 12:04 PM   #37
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Quote:
Originally Posted by M3SQRD View Post
You've never gone to a new track without a baseline setting? Or an old track that's been completely repaved? I can think of other reasons why you might want to adjust ride height while at the track.

On your RS1s, did you check the pressures on the adjustable internal N2 reservoirs? If the N2 pressure was at zero the damper would not feel "precise". Being able to adjust N2 internal pressure is a nice feature the Ohlins do not have.

I'm actually disappointed with the Ohlins R&T setup because it appears to be biased too far toward the "Road" (you've even stated this) and it even shows up in the spring rates - my wife runs 400/672 rates on her RS1 setup and finds it to be very comfy on the street!
We are completely off the topic now.

Apologies to the OP.
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      03-21-2013, 04:43 AM   #38
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Quote:
Originally Posted by jbraslins View Post
My car is a DD that will see at most 3..4 HPDEs a year. I was not happy with OEM ride when I got it. I have H&R sport lowering springs now, and while it made the car stance look good and improved roll resistance and some handling, it definitely is more harsh now and tends to side-step quite a bit over bumps mid-corner. It just feels very nervous mid-corner over uneven pavement.

I was specifically looking for a setup biased more towards road performance and comfort. I got a baby seat in the back and my wife and daughter ride with me very often. Ohlins R&T was an option and at 25% less than JRZ, I think it's a good option indeed. I've done probably close to 40+ track days on my bikes and some amateur motorcycle racing, and all my bikes had Ohlins shocks and fork internals. I have a lot of respect for Ohlins as a company and their build quality is beyond superb. I'll give them a try any day.

So, my expectations are high. I expect that on the road during my daily commute, it will feel more comfortable than stock suspension, and definitely more comfortable than H&R Sport lowering springs.

I also expect that on the road, when car is pushed, it will handle greatly and much better than OEM/H&R. Most importantly I have several very curvy roads with a lot of bumps and crests that I want this car to handle gracefully and confidence inspiring. This will be my first test as soon as these are installed and car is aligned.

I have never tracked my E90 M3, only my E46 M3, so unfortunately I will not be able to provide a good before/after comparison of OEM handling vs. Ohlins @ track. But i should be able to give you my impressions and add some videos where lap times will be indicative of how good this setup is.
Sorry for getting off topic.

I have nothing against Ohlins - I'm running their R&T's on my R56 Mini. Compared to the e9x M3 OEM suspension, the Ohlins R&T suspension will significantly out perform it on the street and track. Have fun and enjoy
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      03-21-2013, 12:48 PM   #39
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Quote:
Originally Posted by M3SQRD View Post
So you've never adjusted ride height at the track to deal with "steady state" handling issues, like midcorner understeer or oversteer? It's not that difficult to make adjustments to compensate for changes in ride height.
Wait, no. You don't use ride height to adjust understeer or oversteer.

I can see adjusting damping as a bandaid for that, but it should be tuned with spring rate and possibly front sway bars... (typically you'd leave the rear alone to help put power down)

But no, ride height does not adjust understeer or oversteer in a proper setup and you'd never adjust ride height at the track without an alignment rack.
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      03-21-2013, 02:06 PM   #40
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Quote:
Originally Posted by kitw View Post
Wait, no. You don't use ride height to adjust understeer or oversteer.

I can see adjusting damping as a bandaid for that, but it should be tuned with spring rate and possibly front sway bars... (typically you'd leave the rear alone to help put power down)

But no, ride height does not adjust understeer or oversteer in a proper setup and you'd never adjust ride height at the track without an alignment rack.
Damping cannot be used to adjust "steady state" cornering - need damper piston rod velocity to create damping forces.

Yes, you can adjust ride height to deal with specific "steady state" handling issues while at the track as well as sway bars to adjust other handling issues without requiring a complete alignment. It usually doesn't require huge changes in ride height to dial out, say, oversteer - if you lower the rear 1/4", while keeping the front height fixed (always work on the end that's lacking grip) you improve overall grip. I've worked with pro drivers at the track and, even after driving my car, they've recommended changes in only ride height.
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      03-21-2013, 03:22 PM   #41
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Quote:
Originally Posted by M3SQRD View Post
Damping cannot be used to adjust "steady state" cornering - need damper piston rod velocity to create damping forces.

Yes, you can adjust ride height to deal with specific "steady state" handling issues while at the track as well as sway bars to adjust other handling issues without requiring a complete alignment. It usually doesn't require huge changes in ride height to dial out, say, oversteer - if you lower the rear 1/4", while keeping the front height fixed (always work on the end that's lacking grip) you improve overall grip. I've worked with pro drivers at the track and, even after driving my car, they've recommended changes in only ride height.
err... most "pro drivers" can't adjust a car to save their life.

"pro drivers" will have an engineer to make those changes.

But no, ride height to increase grip? Maybe on a car with huge aero grip, but ride height alone won't change balance.
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      03-21-2013, 03:27 PM   #42
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Quote:
Originally Posted by kitw View Post
err... most "pro drivers" can't adjust a car to save their life.

"pro drivers" will have an engineer to make those changes.

But no, ride height to increase grip? Maybe on a car with huge aero grip, but ride height alone won't change balance.
Ride heights will change your balance, I have used it to fine tune handling even on my M3. A good shop will know what they are doing with your feedback.
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      03-21-2013, 03:43 PM   #43
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Quote:
Originally Posted by STALKER View Post
Ride heights will change your balance, I have used it to fine tune handling even on my M3. A good shop will know what they are doing with your feedback.
Again, ride height alone will not affect corner balance, unless your corner weights are drastically off. Sure, you start crashing into the bump stops at some level (lower with the Ohlins) but the only way ride height factors into balance is with the camber curve. Since a Macpherson strut gains little camber once you lower it too much, often times raising the static ride height gives you more grip on the front.

And, you never change ride height without either knowing what the alignment will be at a given height (problematic because you need to remove the lower fork on the Ohlins, and most suspensions for our cars don't have a separate ride height adjustment) or without the ability to do a trackside alignment. Toe changes pretty quickly with ride height both front and rear.
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      03-21-2013, 04:47 PM   #44
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Quote:
Originally Posted by kitw View Post
Again, ride height alone will not affect corner balance, unless your corner weights are drastically off. Sure, you start crashing into the bump stops at some level (lower with the Ohlins) but the only way ride height factors into balance is with the camber curve. Since a Macpherson strut gains little camber once you lower it too much, often times raising the static ride height gives you more grip on the front.

And, you never change ride height without either knowing what the alignment will be at a given height (problematic because you need to remove the lower fork on the Ohlins, and most suspensions for our cars don't have a separate ride height adjustment) or without the ability to do a trackside alignment. Toe changes pretty quickly with ride height both front and rear.
There's no point in discussing suspension setup with you - you make different adjustments depending on whether you have oversteer-understeer at turn-in, mid-corner or track out. Also the type of change depends on whether it's a dynamic or static handling issues. Adjusting ride height is one of the adjstment options.

OP - sorry for getting off topic again. This is the last time I'll post in your thread. I hope you enjoy your new Ohlins R&T suspension
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