Ohlins Dedicated Track Coilover Kit

diego895 wrote

Old post, but anyone go from R&T to Dedicated Track and can provide experience on how much harsher on the street?

I ordered R&T and was sent Dedicated Track and want to see if I should exchange them or if I should try out the Dedicated Track. My car is a weekend car, but not a track car, I generally use for road trips and spirited driving

Saw Slicer's video on the differences and interesting that the rear is that much shorter. Having camber plates included is nice

Thanks
Diego

slcook54 did

derbo wrote

slcook54 did

I went from track day kit to dedicated track. Never ran R&T. I wouldn’t go more aggressive than the track day kit for a street car. Dedicated is fairly stiff.

diego895 wrote

Old post, but anyone go from R&T to Dedicated Track and can provide experience on how much harsher on the street?

I ordered R&T and was sent Dedicated Track and want to see if I should exchange them or if I should try out the Dedicated Track. My car is a weekend car, but not a track car, I generally use for road trips and spirited driving

Saw Slicer's video on the differences and interesting that the rear is that much shorter. Having camber plates included is nice

Thanks
Diego

I went from R/T to dedicated track. You can definitely feel a difference in street comfort on the R/T's vs the dedicated. Dedicated Tracks arent terrible on the street but the step up in spring rates you can feel. If ride comfort is more important to you the R/T's are going to be better.

Thanks for the feedback slcook54 and kevin @ eas. The spring rates are pretty high on the Dedicated Track. I'll exchange them for the R&T since my car is a street car. Was just so tempted to put these on since they're right in front of me haha

Dedicated track kit is great. I've been running it for 1.5 years now and I love it. They handle great and honestly, they're not bad on the street.

I had R&T on my e46 but ended up switching the springs to swift springs so they felt pretty comparable to these.. The shocks are better on the dedicated kit though. I can tell especially driving fast with imperfections on the road and the vehicles stability.

I recently installed the Ohlins Dedicated Track kit. I'd like to share some observation so far and seek some advice on settings.

My car is E90 M3 Comp. Ohlins' recommended height settings appeared to be way off. The front was much higher than rear (reverse rake). I moved the front height adjuster all the way up while maintaining the spring preload. The front is about 25mm lower than the recommended default. I also raised the rear by about 15mm from the recommended default to create about 10mm rake. Would like to know your height settings.

For rebound adjustments, Ohlins recommends 9 clicks front / 15 clicks rear for track use. That's a fairly soft (fewer clicks == firm). I'd love to hear your input on track settings.

Thanks!

MPowerZ_32 wrote

I recently installed the Ohlins Dedicated Track kit. I'd like to share some observation so far and seek some advice on settings.

My car is E90 M3 Comp. Ohlins' recommended height settings appeared to be way off. The front was much higher than rear (reverse rake). I moved the front height adjuster all the way up while maintaining the spring preload. The front is about 25mm lower than the recommended default. I also raised the rear by about 15mm from the recommended default to create about 10mm rake. Would like to know your height settings.

For rebound adjustments, Ohlins recommends 9 clicks front / 15 clicks rear for track use. That's a fairly soft (fewer clicks == firm). I'd love to hear your input on track settings.

Thanks!

You have to do your own height adjustments I felt the same way that their recommendations were way off and looked silly.

Setting preload is super important. Also, I’m currently running 6 clicks back from fullstiff upfront and 8 clicks from stiff on the rear.

Turn everything to full stiff, drive it around the block for a minute to get a feel then dial back to your comfort level.

1FastSicilian Thanks for chiming in!

I'm currently running 15 clicks from fullstiff front and back for street. The suspension is firmer than stock ZCP but compliant enough.

I will go to Streets of Willow in a week and run Toyo R888R. The car is otherwise stock outside of Ohlins. Since it's going to be the first time at the track with this setup I'm curious what initial settings I should start with. I'm thinking 5 front and 7 rear from fullstiff. Any input is appreciated!

I’m 6 clicks from full stiff.

MPowerZ_32 wrote

1FastSicilian Thanks for chiming in!

I'm currently running 15 clicks from fullstiff front and back for street. The suspension is firmer than stock ZCP but compliant enough.

I will go to Streets of Willow in a week and run Toyo R888R. The car is otherwise stock outside of Ohlins. Since it's going to be the first time at the track with this setup I'm curious what initial settings I should start with. I'm thinking 5 front and 7 rear from fullstiff. Any input is appreciated!

That’s a good starting point, from there you can adjust as your day goes on. I keep the notebook they provided in my car with a journal of what settings I ran on at which track along with tire pressure.

You’ll enjoy these coilovers.

Stumbled upon this thread looking for the correct preload, height adjustment and the measurement between the two perches. Per the instructions its 184mm (preload), 133mm (height adjustment) and 147mm (between the perches) but all 3 of those numbers cant be correct at least as far as mine are assembled. I assume the 184mm preload is correct, but does anyone have a base starting point for height?

I am coming from the R&T so can I use the distance between the top of the spring and the height adjuster on those as a reference point or are they completely different designs in that respect?

e92BMW///M3 wrote

Stumbled upon this thread looking for the correct preload, height adjustment and the measurement between the two perches. Per the instructions its 184mm (preload), 133mm (height adjustment) and 147mm (between the perches) but all 3 of those numbers cant be correct at least as far as mine are assembled. I assume the 184mm preload is correct, but does anyone have a base starting point for height?

I am coming from the R&T so can I use the distance between the top of the spring and the height adjuster on those as a reference point or are they completely different designs in that respect?

If you purchased it pre-assembled from 3DM, do not change the preload. It will be correct out of the box despite what the manual says. You should only need to adjust height as needed. Do not follow what the manual says in terms of trying to measure the different lengths, it will not be close. Best bet is to install it and adjust height accordingly from that baseline.

I didn’t buy from 3DM so any guidelines is helpful.

e92BMW///M3 wrote

I didn’t buy from 3DM so any guidelines is helpful.

You could try the general guideline of 1/4" preload or about 2-3 turns once snug. Every turn should equal about 2mm.

e92BMW///M3 wrote

Stumbled upon this thread looking for the correct preload, height adjustment and the measurement between the two perches. Per the instructions its 184mm (preload), 133mm (height adjustment) and 147mm (between the perches) but all 3 of those numbers cant be correct at least as far as mine are assembled. I assume the 184mm preload is correct, but does anyone have a base starting point for height?

I am coming from the R&T so can I use the distance between the top of the spring and the height adjuster on those as a reference point or are they completely different designs in that respect?

What spring rates and lengths did your R&Ts come with? The R&T user’s manual is either for 90/190 N/mm or 90/230 N/mm (two different spring rates offered by Ohlins). There are three R&T setups with different spring rates from above and they’ll definitely have different preload and ride height lengths. Verify your rates and confirm you’re referencing a manual with the same rates.

M3SQRD wrote

What spring rates and lengths did your R&Ts come with? The R&T userÂ’s manual is either for 90/190 N/mm or 90/230 N/mm (two different spring rates offered by Ohlins). There are three R&T setups with different spring rates from above and theyÂ’ll definitely have different preload and ride height lengths. Verify your rates and confirm youÂ’re referencing a manual with the same rates.

I have the Dedicated Track, front rates are 120N/mm (6") and the rear are 180 N/mm (8"). The specs on the springs themselves compared to the manual were the same.

The spring assembly preload length in the front per the manual is 184mm, which puts it right at the end of the threads (but fully engaged, so not an issue) but in order to get the height of the vehicle to anything resembling a reasonable height I am all the way at the top (lowest setting) of the height adjustment). and even with that setting I am sitting higher than I was with the R&T kit I had previously.

The rear is the inverse situation where the spring has an incredible amount of play when using their suggested preload height adjustment when the suspension is at full droop. I haven't spent much time on the rear but it does seem like there is enough adjustability to get everything snug but I am looking for some settings as a baseline from someone that actually has these installed vs. just guessing and checking to make sure I have the right ratio of spring/damper.

I messaged 3DM (who I didn't buy from, but per these boards seems to be the most knowledgeable) and will call Ohlins directly this AM to try to get it sorted.

e92BMW///M3 wrote

I have the Dedicated Track, front rates are 120N/mm (6") and the rear are 180 N/mm (8"). The specs on the springs themselves compared to the manual were the same.

The spring assembly preload length in the front per the manual is 184mm, which puts it right at the end of the threads (but fully engaged, so not an issue) but in order to get the height of the vehicle to anything resembling a reasonable height I am all the way at the top (lowest setting) of the height adjustment). and even with that setting I am sitting higher than I was with the R&T kit I had previously.

The rear is the inverse situation where the spring has an incredible amount of play when using their suggested preload height adjustment when the suspension is at full droop. I haven't spent much time on the rear but it does seem like there is enough adjustability to get everything snug but I am looking for some settings as a baseline from someone that actually has these installed vs. just guessing and checking to make sure I have the right ratio of spring/damper.

I messaged 3DM (who I didn't buy from, but per these boards seems to be the most knowledgeable) and will call Ohlins directly this AM to try to get it sorted.

I can’t find the dedicated track installation guide online. I know the standard R&T installation guide results in only 10-15 mm of lowering front and rear.

3DM is a certified Ohlins (TTX and R&T) damper service/rebuild shop so they are extremely knowledgeable of how to setup the dedicated track kit (offered by Ohlins; 3DM offers their own track day setup). Dedicated track has similar lowering to the standard kit except for different lengths based on different springs. From what I’ve seen on the forum, I’d say there are only 5-10 forum members running the dedicated track setup (could be more but it’s 5-10 who have posted about it). Personally, I’d set it up with the lowering I wanted with minimal forward rake (1/4-3/8” measured between the center of the rear and front jack pads, front jack pad is lower) so I’d be close to being corner balanced (cross weights would be off a little). I’d set the rear to 20 mm (0.79”) first and then set the front rake. Getting the car corner balanced is worth the cost.

I ended up going with the recommended front setting for now and in the rear I increased the height slightly (334mm to the end of the strut vs. 325 in the instructions) and the spring height of 59mm (vs. 48mm in the instructions). I am hoping the front settles just a touch. also going to pick up a 5mm and 10mm spacer so I can try to fit more tire and still clear the front.

e92BMW///M3 wrote

I ended up going with the recommended front setting for now and in the rear I increased the height slightly (334mm to the end of the strut vs. 325 in the instructions) and the spring height of 59mm (vs. 48mm in the instructions). I am hoping the front settles just a touch. also going to pick up a 5mm and 10mm spacer so I can try to fit more tire and still clear the front.

Sounds like your car has a nicely balanced front rake vs. the slammed < 1 finger gap front and rear. Just pay attention to how your car handles at corner entry, mid corner and corner exit to determine if your ride heights are setup well and what damper settings perform best. It can be difficult to get the rear to rotate with 120/180 N/mm spring rates especially with sticky wide tires. Increasing damping closer to critical or over damped can help but then it compromises other corners and/or braking zones.

M3SQRD wrote

Sounds like your car has a nicely balanced front rake vs. the slammed < 1 finger gap front and rear. Just pay attention to how your car handles at corner entry, mid corner and corner exit to determine if your ride heights are setup well and what damper settings perform best. It can be difficult to get the rear to rotate with 120/180 N/mm spring rates especially with sticky wide tires. Increasing damping closer to critical or over damped can help but then it compromises other corners and/or braking zones.

How can spring rate influence rotation? I have tried many suspensions from OEM hardness to 150nm in full coilover. I can give you 3 examples, number 1 is the one that rotates the best and number 3 the worst.

1. M4 GTS oem alignment, 275/285, kw clubsport

2. M3 E92 295square, -2° front camber 0toe, rear -2° camber, toe in 3mm total, drexler diff, nitron r3 140/150nm.

2. M2 Competition, 295square -2° front camber, toe out 1.5mm total, rear camber -1.5° toe in 3.5mm total, drexler diff, mcs 140/120nm


None of these three care about spring rate to rotate.

Track/S wrote

How can spring rate influence rotation? I have tried many suspensions from OEM hardness to 150nm in full coilover. I can give you 3 examples, number 1 is the one that rotates the best and number 3 the worst.

1. M4 GTS oem alignment, 275/285, kw clubsport

2. M3 E92 295square, -2° front camber 0toe, rear -2° camber, toe in 3mm total, drexler diff, nitron r3 140/150nm.

2. M2 Competition, 295square -2° front camber, toe out 1.5mm total, rear camber -1.5° toe in 3.5mm total, drexler diff, mcs 140/120nm


None of these three care about spring rate to rotate.

There are two ways to increase front roll stiffness:
1. Spring rates
2. Anti-sway bar (ASB) stiffness

Roll is due to an inertial torsional loading (J_axial*Alpha_axial = T_axial) along the axis of the car. Assuming there’s no ASB (links disconnected), the torsional loading is reacted as a force couple by the front springs, Torque = W_spring x spring force (a force couple of equal and opposite spring forces) where W_spring is the distance from spring centerline to spring centerline (sine of strut angle should be accounted for but for simplicity I’m ignoring it). The roll angle, for a fixed force couple, is a function of the spring rate x force couple (strut bump/droop displacement) so softer springs means there’s a larger roll angle vs. stiffer springs means there’s a smaller roll angle. In reality, the ASB contributes to the roll stiffness. Spring rates and ASB axial/vertical stiffness should be converted to wheel rates (WR) based on their respective motion ratios (MR) squared (e.g., WRspring = MRspring^2 x spring rate) and the spring & ASB WR axial/vertical stiffnesses are added to get the combined roll stiffness.

How does spring rate not affect roll stiffness?

People think the front can be too stiff.
Excessive toe. Response isn't grip. And cranking it on like in Ex3 is just two counteracting forces. Toe is a form of yaw damping. Toe out will always be dull midcorner, where rotation is required. It counteracts Ackerman introduced in the geometry.
It does not surprise me that some people, that are not overly reliant on response (aka talent), can take advantage of more grip with slight toe in front and zero toe rear as well.