[bNks334]

YCW Engineering has been promoting one of their latest developments for the E9x/E8x, Coilovers! Although at first the name may not sound all that familiar, YCW is the parent company of MFactory. MFactory is a brand that has continuously filled gaps in the BMW market with high quality products. They utilize in-house engineering and machining to deliver tailored products at an affordable cost all while working WITH the community.

YCW released their coilovers for multiple platforms simultaneously. Positive reviews are coming in from the BRZ, Focus ST, 350z, and many other forums!

Link to the official product page: http://store.ycwengineering.com/cata...no/YCW-REF-E87

Key features:
These coilovers provide many desirable features that in my eyes separates them from just about anything close in price:
• Front - Independent height and spring adjustable
• True spherical (pillowball) top mount replaces OE mounts
• Radial spring perch allows spring to spin freely (bind free when steering)
• Integrated camber plate reduces stack height vs adding an aftermarket plate
• Separate Camber (4*) and Caster adjustment
• Optional custom spring rates
• Digressive damping
• Meaningful damping adjustment (7 levels)
• Shock covers!
• Adjustable End-links
• Min. Front lowering: 40mm with a 4k spring or 7-10mm with a 6k spring*****
• Min. Rear lowering: 30mm with a 12k spring or 10mm with a 16K spring*****

***** will also depend on spring preload and length!!



Unboxing:
The coilovers arrived within a few days of shipping from YCW's west coast warehouse and distribution center. They came well packaged and protected from any damage that could possibly occur during shipping. All aspects were definitely covered in this regard. Best packaging I’ve seen:


Installation and Setup:
The coilover pieces came packaged and assembled as they are to be installed on the car.


Feel free to reach out, or post here, if you need any help. There are plenty of resources already available that can give you a general idea on how to install coilovers:

Tips:
• There is no need to remove the cowl or the strut bar. Simply remove the Torx bolt (E14 Or 11mm) and push the bar out of the way to access the top mount bolts (3x 10mm stock and 3x 12mm YCW).
• Make sure you have an 18mm socket and wrench (ratcheting preferred) to loosen the bolt that clamps the strut into the knuckle
• Use two 3/8” drive bits/adapters to spread the knuckle and free the strut
• Protect your fender with tape (yes you’ll end up chipping paint trying to get the OE struts out)
• Cut the wheel all the way to the opposite direction you’re working on to ease removal of OE struts
• Loosen lower control arms at chassis if you still need more clearance to get the OE strut out. Base suspension requires doing this, but sport suspension should come right out. Always re-torque control arms AT RIDE HEIGHT.
• Have more than one jack handy to line things back up and support the knuckle as you work
• You get adjustable endlinks with the coilovers. Endlinks need to be shortened as you lower your ride height. The sway bar tabs should be kept parallel to the ground, or close to it. This should be done with the car sitting at ride height (put it on ramps).

Front:
Use some common sense when installing... things can really only fit together one way. I don’t remember if the left/right front struts were labeled, but the swaybar mounting tab will be in the wrong location if you try to install the struts on the incorrect side. I put 1/4" of preload (spring length measures 6.75") on the spring to keep it tight under droop travel. Springs also lose a bit of height over time. With a 6k front spring, rebound damping feels good to me at about 2-3 clicks "tighter" (3/7 - 4/7).

Take note of the camber plate orientation! It can only be mounted one way. My coilovers came with the camber plates installed on the wrong side. It only took a few seconds to swap the plates before installing.


Tire fitment is TIGHT on the E82. In order to gain every mm of possible tire fitment, I found it necessary to upgrade to a custom SWIFT 180mm spring. This moved the spring perch up 40mm (220mm to 180mm spring) and I was able to fit my 17x9 wheels with 255 tires (ET38).


Rear:
Again, use common sense. Things look odd at first because the rear strut is inverted (upside down), but they can only be mounted one way!

I threaded in the rear strut approximately 35mm. This measures 9 1/4" as seen below. Bump travel and droop travel in the rear have been sufficient on the street at around 2” in each direction. With a 16k rear spring, rebound damping feels good to me at about 2-3 clicks "tighter" (3/7 - 4/7).


Here are some comparison shots between YCW and stock:


Rake:
A stock M-sport E82 (17" wheels) sits at 580mm in the front and 572mm in the rear. That creates a larger front wheel gap than the rear (visually) with the car appearing to sit almost .25” higher than the rear. However, actual rake, as measured by ground clearance at the side skirt, is around .25" (The rear sits slightly higher than the front despite the wheel gap showing the opposite). I maintained a small rake angle with my ride height settings and I have the rear sitting about .25" higher off the ground than the front of the car.

Ride height:
With the 4k 180mm SWIFT springs installed, ride height and suspension travel were a bit low for my taste and performance goals. I was able to get a maximum ground clearance up front of about 4.25". I then tried dialing in .5-.75" of pre-load up front to maintain a higher ride height. However, this resulted in coil bind over large potholes with the shorter 4K SWIFT 180mm springs installed. I ended up moving back to a 6K 180mm spring and my ride height is now at around 5-1/8" front and 5-3/8" rear. This is roughly 7mm lower than BMWPS up front and 10mm lower than BMWPS in the rear.

E82 stock ride heights:




Excuse the dirty car:



Things that can affect ride quality (bounce):

Spring rates:
One of the drawbacks of a McPherson front suspension is that the camber curve has a tendency to go positive as the chassis compresses under load (braking/cornering). One common way to offset this is by running a stiffer front spring rate to prevent the front suspension from ever compressing in the first place. While this may work, people tend to increase the front spring rate more than the rear. This upsets the natural frequency bias of the front and rear springs. This imbalance will change handling behavior. Most notably, mid-corner under-steer.

Motion ratios and corner weight can be used to see how effective a spring is after taking suspension dynamics into consideration. The motion ratio of the E82/E90 dictates that the front and rear springs should be kept at close to a 1:3 ratio to maintain a neutral natural frequency (flat ride). The further you deviate from this 1:3 ratio the more out of sync your springs will be as they oscillate under load (bouncy feeling) and the more specifically tuned your damping will need to be to handicap it.

Here is a spreadsheet I put together that you can use to get a starting point on how stiffly sprung you want your car to be. I personally shot for ~2Hz which is right around that 6k/18k mark. The spreadsheet also includes a tab that converts between kg/mm and lb/in. You’ll need to play with the sprung weight per corner for your particular vehicle to get ROUGH estimated spring frequencies: https://drive.google.com/open?id=1VR...8UvX7BwusPj5yw

My personal take on it is that spring rates, and more importantly effective wheels rates, should generally be matched to the amount of grip your tires can generate. Total wheel rate should take into consideration all sources of stiffness from sway bars to binding suspension components. There is no sense in running race-car like spring rates of 2.5HZ+ if you drive around on 205/50 all-seasons. You simply won’t generate enough g-force to make use of the springs. You’ll slide around everywhere (understeer/oversteer). With that being said, your coilovers do restrict what rates you can run. If you go too soft, you'll run out of suspension travel.

A 6k/18k rate works well for these coilovers. I personally may move to 8k/20k in the near future to get a better bump/droop travel distribution and ride height adjustment (back to stock with 0 pre-load).

Rear shock mounts:
I strongly advise you take installing coilovers as an opportunity to overhaul your rear shock mounts. Here is a quick clip of how poorly the stock mounts handle stiffer spring rates:

You can see how much the stock mounts flex and I am only putting my body weight on the bumper. This will create a sensation of “bounce” since the motion is not being damped by the strut.

Pretty much the best/cheapest solution I found was MONROE shock mounts carried at a local auto parts store (Pepboys). These mounts are made of a hard rubber instead of foam the stock mounts are made of. I could instantly feel the difference in the strut damping once I got these mounts installed.

Monroe 907984 & 907985:


Tires:
Stiffer spring rates shift load to your tires. If you are going to up your springs rates significantly then you’re going to want to look at what tires you’re running and how stiff the sidewalls are. To outline the effect of tire construction on suspension feel, I compared how stiff the sidewalls are in a winter tire vs a summer tire (200tw category). Using a soft sidewall winter tire will result in a bouncy ride as the sidewall deflection will go un-damped. Here is the comparison:

Winter Tires at 40psi:

Summer tires at only 30psi:

Alignment:
Alignment is going to be mandatory after installing coilovers. As with everything suspension related, alignment settings are a trade-off.

Camber: Front -1.5 to -2.5*
Rear -1.5* to -2*

Dialing in static negative camber up front helps offset the dynamic change in camber that occurs under load that I talked about earlier. This allows the car to corner flatter in corners, but it also reduces straight line stability. Anything over 3* is excessive for a dual purpose car (imo). Most racing classes don't even allow more than 3-3.5* of camber. I also keep rear camber around -1.8* as a trade-off between cornering and reducing rear straight-line traction. With -2.2* camber I was right at the wear bars of extreme performance 200TW tires. I now have -2.6* camber with 80TW tires and the tires chalk out right on the wear bars.

Toe: Front 0*
Rear .3* total (.15* per side)

Toe is the same deal as camber. Toe-in (positive toe) aids in straight line stability. Toe-out can aid in agility and turn-in, but the car will feel darty on the street if you move toward too much toe-out. Either toe setting is going to increase the RATE of tire wear since the tires will be pigeon toed and dragged down the road. Again, it's a trade-off. The Mcpherson front suspension toes-out as it compresses, so, 0* up front works well for me as a dual purpose car. I kept a little toe-in (positive toe) in the rear for straight line stability and increased traction on acceleration (all that torque is tough to put down).

Caster: 7-8*

Caster is fairly high on a stock car as is. For that reason, I did not dial in any additional caster when installing the coilovers. Caster can also impact the camber curve as it alters the steering axis inclination. Alignment sheet came back at 7.3* with the camber plates pushed as far forward as they can go. Some of the affects of caster are steering effort and the wheels ability to return to center.

Driving Impressions:
Just to note, these coilovers use linear springs and digressive damping. The ride on the street IS NOT going to feel like many other coilovers. Coilovers in this price range, like ST, use progressive spring rates and standard damping which provide for a less sporty and a more plush ride.

These coilovers have been fantastic. Not only have they held up through their first Northeastern winter, but they provide a phenomenal improvement in performance and adjustability over a standard strut and spring pairing. The damping adjustment provides a wide range of rebound that adequately damps the 4/12k and 6K/16K springs rates I have tried. My only feedback is the resulting ride height and bump travel. I think 8K/20K is about as ideal as it gets in that regard. Those rates would give you a more desirable BUMP/DROOP travel distribution (60/40) and keep you off the bump stops.

YCW has been excellent to work with throughout the test phase of the coilovers. I get a response within a few hours of emailing them. If anyone is considering buying any of the other mid-tier BMW suspensions, I highly suggest they look to YCW first and TRY to find a reason not to buy the YCW instead. You’ll be hard pressed to find another vendor that offers the same features and functionality for less.

[bNks334]

Bump - updated some details.

[Go Horns!]

Thanks for the review. Have you tested the range of adjustbility? How would you compare full-soft to the m-sport suspension? What setting do you normall drive on?

[Banana Clipper]

Christ man, brav-fn-o, blew my review out the water. I'm going to steal some of your pointers from this review as well. Thanks!

[bbnks2]

Originally Posted by Go Horns!

Thanks for the review. Have you tested the range of adjustbility? How would you compare full-soft to the m-sport suspension? What setting do you normall drive on?

I don't know exactly what you're asking so maybe this helps...

The curb weight of each car tells a different story; to summarize, the 335i Coupe is laden with 3,542 lbs, the 335iS with 3,650 lbs while the M3 tips 3,704 lbs at the scales.

Your chassis weight is going to effect your results vs. my results with an E82 @ 3220. With an extra ~100lb of un-sprung weight per corner your car is going to sit .44" lower (100/224 lb/in). I am guessing the E9x also sits a bit higher stock (more ground clearance) and has bigger wheel arch gaps. So, You might be happy with the little extra decrease in ride height? I can't say for sure since I don't have an E9x to measure.

M-sport suspension on an E92 @ 3600lbs runs 145/460 spring rates. That provides for a pretty soft luxury ride. YCW 4k/12k = 224/672 which gives you springs rates higher than what an M3 runs (E92 M3:160/550 lb/in @3700lbs). Hopefully that gives you an idea of how "sporty" the car is going to feel. The ride is still comfortable enough for me on the street, but it handles like a sport car now instead of a luxury boat.

Damping is a bit subjective. The settings you choose depend on your driving style and how you want the car to react. Over winter, I kept damping low at 2-3 notches. We were also still getting snow here up to a few weeks ago. Cold weather also makes the strut oil a bit thicker so you can dial things back a bit to keep it softer.

[bbnks2]

Originally Posted by Banana Clipper

Christ man, brav-fn-o, blew my review out the water. I'm going to steal some of your pointers from this review as well. Thanks!

You have 6k/12k, right? How are things working out for you?

YCW didn't get the detailed feedback from the community that they were expecting and my E82 experience is going to be different than the E9x.

[Banana Clipper]

Originally Posted by bbnks2

You have 6k/12k, right? How are things working out for you?

YCW didn't get the detailed feedback from the community that they were expecting and my E82 experience is going to be different than the E9x.

TBH I'm not 100% which spring rates I have. I got the 'street' setup. I had a steep 'learning' curve with the YCW's but its all squared away now. I dont really have bounciness, at least I dont believe I do, from the rear but after seeing your short clip I figured it couldnt hurt to replace the upper and lower mounts since they do have almost 80k miles on them. I have the same clearance issues in the front but I'm timid to swap out the swift springs since I am pretty happy with my ride and it has prove to be able to handle the hills and the 1/4 mile. With that said, my camber plates are backwards as well, kind of a shame the alignment shop didnt catch that since they should know better than I, so that gives me reason to drop the front again.

Either way, I've been more than pleased with the YCW's as well and they are a stellar buy at that price point. I believe the last time I talked about the YCW's I noted that most of the problems with the YCW's is that I didnt know what I was doing with them not that they actually had any problems. You REALLY do get more than you're paying for with these things and I know MFactory says theyre comparable to KWv2 but I think theyre more like something in between a v2 and v3 tbh

Anywho, didnt mean to thread jack. I was just really impressed by your review and made me feel bad about the perspective and actual feedback I gave in mine since yours is so well written. Again, bravo brotha, great review, you nailed it!

[bNks334]

Originally Posted by Banana Clipper

TBH I'm not 100% which spring rates I have. I got the 'street' setup. I had a steep 'learning' curve with the YCW's but its all squared away now. I dont really have bounciness, at least I dont believe I do, from the rear but after seeing your short clip I figured it couldnt hurt to replace the upper and lower mounts since they do have almost 80k miles on them. I have the same clearance issues in the front but I'm timid to swap out the swift springs since I am pretty happy with my ride and it has prove to be able to handle the hills and the 1/4 mile. With that said, my camber plates are backwards as well, kind of a shame the alignment shop didnt catch that since they should know better than I, so that gives me reason to drop the front again.

Either way, I've been more than pleased with the YCW's as well and they are a stellar buy at that price point. I believe the last time I talked about the YCW's I noted that most of the problems with the YCW's is that I didnt know what I was doing with them not that they actually had any problems. You REALLY do get more than you're paying for with these things and I know MFactory says theyre comparable to KWv2 but I think theyre more like something in between a v2 and v3 tbh

Anywho, didnt mean to thread jack. I was just really impressed by your review and made me feel bad about the perspective and actual feedback I gave in mine since yours is so well written. Again, bravo brotha, great review, you nailed it!

Wanting wider wheels up front is more for my Track/autocross use. It's a non-issue for most people as well as the minimum lowering amounts. Detailing everything I've done should give people an idea of where to start if they want to make some of these custom changes as well. All you have to do is some math and avoid all my trial and error lol.

Most people just want a stiffer ride and a nice low sporty look. Skinny front tires are usually better for 1/4 racing anyway. Less rotational mass and less friction to push down the track or something like that lol...

[Jeff@TopGearSolutions]

Props for the thorough review. I debated on replacing my KW's with these. Still on the fence - I really want those camber plates more then anything but the swift springs are a plus too. Decent shock upgrades with coilovers are hard to come by on the X Drive/Xi

[AtlasM]

Interesting, they list an E90 xdrive application although it says "2-3 months" for stock status.

http://store.ycwengineering.com/cata...o/YCW-REF-E92X

(I'm happy with the suspension setup I've put on my xdrive but good to know for those xdrive owners shopping for suspension.)

[Jeff@TopGearSolutions]

Originally Posted by AtlasM

Interesting, they list an E90 xdrive application although it says "2-3 months" for stock status.

http://store.ycwengineering.com/cata...o/YCW-REF-E92X

(I'm happy with the suspension setup I've put on my xdrive but good to know for those xdrive owners shopping for suspension.)

Yea it's a couple months out? What's your full set up, including alignment?

[AtlasM]

Originally Posted by Jeff@TopGearSolutions

Yea it's a couple months out? What's your full set up, including alignment?

Koni FSD shocks
B&G springs
Speedthane COT-58 blue front & Z4M rear bump stops
Ground Control xi camber plates
E93 M3 23.6mm rear sway bar
Adjustable sway bar end links (Ground Control front, Hotchkis rear)
Monroe rear upper & lower shock mounts
Strongflex front tension strut bushings
Strongflex front sway bar bushings
Whiteline rear subframe bushings

I'm running -2.25 camber in front and -2 in the rear. +6 caster in front. Little bit of toe in on both ends.

Overall I'm happy with the looks & handling, so I'm not really in the market for more suspension stuff.



(This pic was before I had the alignment done so the camber isn't as negative but otherwise that's still how it looks.)

[Jeff@TopGearSolutions]

Originally Posted by AtlasM

Koni FSD shocks
B&G springs
Speedthane COT-58 blue front & Z4M rear bump stops
Ground Control xi camber plates
E93 M3 23.6mm rear sway bar
Adjustable sway bar end links (Ground Control front, Hotchkis rear)
Monroe rear upper & lower shock mounts
Strongflex front tension strut bushings
Strongflex front sway bar bushings
Whiteline rear subframe bushings

I'm running -2.25 camber in front and -2 in the rear. +6 caster in front. Little bit of toe in on both ends.

Overall I'm happy with the looks & handling, so I'm not really in the market for more suspension stuff.



(This pic was before I had the alignment done so the camber isn't as negative but otherwise that's still how it looks.)

With that list and specs I can see why you're content.

[bNks334]

Originally Posted by AtlasM

Koni FSD shocks
B&G springs
Speedthane COT-58 blue front & Z4M rear bump stops
Ground Control xi camber plates
E93 M3 23.6mm rear sway bar
Adjustable sway bar end links (Ground Control front, Hotchkis rear)
Monroe rear upper & lower shock mounts
Strongflex front tension strut bushings
Strongflex front sway bar bushings
Whiteline rear subframe bushings

I'm running -2.25 camber in front and -2 in the rear. +6 caster in front. Little bit of toe in on both ends.

Overall I'm happy with the looks & handling, so I'm not really in the market for more suspension stuff.



(This pic was before I had the alignment done so the camber isn't as negative but otherwise that's still how it looks.)

Takes a bit of work to stiffen these cars up a bit. There is no plug and play solution since every part of the suspension is too soft lol

What's your ground clearance front and rear?

[mike082802]

i have these as well sitting in the boxes with the mfactory 6k/12k springs for my 135. i currently have ast4100 with swift 7k/11k springs with dinan camber plates. i am debating paying the 200$ for the upgraded swift springs since i run 245/35 up front. for the price of the GB i figured i would give them a shot. i am pretty happy with the ast, they are more comfortable than the koni yellows and swift r springs i had before. but wanted to try the double digressive pistons on these and really wanted the camber plates these come with. trying to find the time to install these. i have to see if they installed my camber plates backwards as well.

[mike082802]

i also have e93 m3 fsb and upper and lower front control arms with whiteline rsf inserts. i just bought all the megan rear arms and whiteline full rsfb and debating getting a bigger rear sway bar, probably something like a 15mm solid, i run federal rsr tires.

[AtlasM]

Originally Posted by bNks334

Takes a bit of work to stiffen these cars up a bit. There is no plug and play solution since every part of the suspension is too soft lol

What's your ground clearance front and rear?

I haven't measured the clearance, I can do that tonight I suppose.

I love how the B&G springs sit but this is about as low as you'd want to take the front an xi and still have any suspension travel left. I had to get creative with bump stops. Started with E36 M3 stops in front since that's what everybody says to use with lowered E9x, but they were too soft and let the suspension bottom out on sharp impacts. Once I switched to the Speedthane ones it's been much better.

For folks with xi's I would not recommend B&G springs with stock shocks, they need to be paired with proper shocks and bump stops. If you want to get the front of the xi this low it's either this or coilovers.

So to bring it back to the original topic, that's why the YCWs for the xi piqued my interest, at least as far as knowing about options for xi.

My combo of Koni FSD + B&G + GC camber plates + bump stops cost me about $1300 which is actually more than some of the cheaper xi coilovers like ST, Sonic Tuning & BC Racing.

But the things that were important to me were digressive shock valving and camber adjustment. ST has neither, Sonic & BC have camber plates but not digressive shocks.

YCW apparently has digressive shocks and camber plates, plus Swift springs and fancy bearings, for $1849.

Fortune Auto 500 digressive shocks & camber plates for $1474 but adding the Swift springs pushes them up to $1824, or up to $1904 with the radial bearing upgrade.

Same general ballpark for both options, but nice to see a new player with those features.

[bNks334]

Originally Posted by AtlasM

I haven't measured the clearance, I can do that tonight I suppose.

I love how the B&G springs sit but this is about as low as you'd want to take the front an xi and still have any suspension travel left. I had to get creative with bump stops. Started with E36 M3 stops in front since that's what everybody says to use with lowered E9x, but they were too soft and let the suspension bottom out on sharp impacts. Once I switched to the Speedthane ones it's been much better.

For folks with xi's I would not recommend B&G springs with stock shocks, they need to be paired with proper shocks and bump stops. If you want to get the front of the xi this low it's either this or coilovers.

So to bring it back to the original topic, that's why the YCWs for the xi piqued my interest, at least as far as knowing about options for xi.

My combo of Koni FSD + B&G + GC camber plates + bump stops cost me about $1300 which is actually more than some of the cheaper xi coilovers like ST, Sonic Tuning & BC Racing.

But the things that were important to me were digressive shock valving and camber adjustment. ST has neither, Sonic & BC have camber plates but not digressive shocks.

YCW apparently has digressive shocks and camber plates, plus Swift springs and fancy bearings, for $1849.

Fortune Auto 500 digressive shocks & camber plates for $1474 but adding the Swift springs pushes them up to $1824, or up to $1904 with the radial bearing upgrade.

Same general ballpark for both options, but nice to see a new player with those features.

I'll support Mfactory all day over FA or BC. Especially with the pre-order still going on providing for a steep discount.

B&G springs appear to provide a drop of -1.6/-1.4. I can't find the specs on the actual spring rates though.

[AtlasM]

Originally Posted by bNks334

I'll support Mfactory all day over FA or BC. Especially with the pre-order still going on providing for a steep discount.

B&G springs appear to provide a drop of -1.6/-1.4. I can't find the specs on the actual spring rates though.

I agree, at that $1200 pre-order price they're a steal. The E9x xi application isn't on their store for that price but I suppose it wouldn't hurt to ask.

This option didn't exist a year ago when I did my suspension but would be interesting for other E9x xi owners.

I think the lowering specs listed by B&G are for E9x rwd, not sure the exact lowering on xi. I actually asked them about spring rates and they didn't disclose their spring rates to me. They just said "progressive springs roughly 30% stiffer than Eibach Pro-Kit." There are some markings on them of some kind but I can't remember if they were spring rates.

[bNks334]

bump - updated the original thread again. The numbers are starting to become a blur as I've made countless changes to the suspension over the past few weeks, lol.

Currently at 4k/12 with .25" front pre-load (basically 0 preload since the spring losses height as it settles). No coil bind as is (180mm 4k spring), and I haven't noticed any bump stop engagement on the street either with the softer 4k spring rate. The resulting front ride height is low but similar to the ride height most aftermarket springs target. I think it's just about ideal for my goals and maintaining proper suspension geometry. I reduced my rear ride height another 3/8" to reduce the 1" of rake I had previously.

Damping is currently set to 4/7 and 5/7. I may even reduce damping a bit more for the street. The coilovers soak up big dips in the road drastically better than stock. Sharp impacts like potholes are a bit jarring, but that is more of a function of the high linear spring rates and stiff initial damping of the digressive valving.

I will be moving to a 6k/16k setup within the next 2 weeks.

[335Pete]

Here is my xi with the ycw coilovers..My setup has 5k/13k springs with dampening set to 3/7 front and 1/7 rear..Im very impressed with the ride quality that these coilovers offer.. And the service mfactory/ycw offers is outstanding..
If you`re looking to get a new suspension I would strongly suggest these ycw coilovers..

[Julian2485]

Originally Posted by bNks334

bump - updated the original thread again. The numbers are starting to become a blur as I've made countless changes to the suspension over the past few weeks, lol.

Currently at 4k/12 with .25" front pre-load (basically 0 preload since the spring losses height as it settles). No coil bind as is (180mm 4k spring), and I haven't noticed any bump stop engagement on the street either with the softer 4k spring rate. The resulting front ride height is low but similar to the ride height most aftermarket springs target. I think it's just about ideal for my goals and maintaining proper suspension geometry. I reduced my rear ride height another 3/8" to reduce the 1" of rake I had previously.

Damping is currently set to 4/7 and 5/7. I may even reduce damping a bit more for the street. The coilovers soak up big dips in the road drastically better than stock. Sharp impacts like potholes are a bit jarring, but that is more of a function of the high linear spring rates and stiff initial damping of the digressive valving.

I will be moving to a 6k/16k setup within the next 2 weeks.

Why are you going stiffer on spring rate ?