posted on May 11, 2014 13:31
Project FR-S- Ultimatizing Our Suspension With KW 3-Way Adjustable Clubsport Coilovers
If you have been following the build of Project FR-S till now, you have probably noted that we have spent a lot of time working on our suspension and brake systems, laying down the foundation for a really good track car.
If you read our last segment about how our car performed in a track evaluation against both a stock and another well built tuner car you can see just how well our car really does work. Our car's big advantages were in the braking and handling departments with both of our resident pro drivers, Tyler McQuarrie and Dai Yoshihara, raving about how well our car works.
Could we make our superbly handling car even better? We are sure going to try and with some new developments from KW Suspension we think we can definitely make our car even better, especially as we start to upgrade our car with more and more power. Since we last wrote about coilovers on our car, KW Suspension has since come out with some 3-way adjustable Clubsport coilover. Are these the ultimate street capable shocks? Read on.
The KW Suspension 3-way adjustable Clubsport coilovers are an unusual shock. They have the adjustability and performance of a high end Motorsports damper but with the corrosion resistance and durability features of an all weather daily driving street shock. The seals and bushing are all appropriate for long term use. Motorsports dampers tend to worry about friction first and long term sealing second. The 3-Way Clubsports have dust shields and scraper seals for long service between rebuilds. The spindle mounting tabs are slotted for additional camber adjustments to supplement the camber plate.
The front 3-way Clubsports come with a camber plate. The design is really good as it has a super low stack height and lowers the car an additional .5 inch without sacrificing bump travel. The upper bearing is a high quality corrosion resistant stainless part that is fully sealed. The Variant 3 shocks use the stock rubber upper which is better for NVH reduction but the bearing used in the camber plates puts every bit of wheel motion through the damper instead of flexing rubber.
The 3-way Clubsports have a remote reservoir with the high and low speed compression adjusters mounted at the bottom of the canister. You can also see the stainless reinforced corrosion proof plastic spring seat. You can drive these coilover all winter in the rust belt and the collar will still turn freely afterwards. Other coilovers seize up solid under the same conditions.
The rear 3-Way Clubsport shock uses a bearing equipped top mount to get rid of the squishy rubber. Like the front camber plate, the rear top mount uses a corrosion resistant well sealed bearing. Bearing mounts transfer a little more noise and vibration into the cabin, particularly in the rear. However putting all movement under damper control makes a big difference that a driver can easily feel.
Monday, May 12, 2014 11:32 AM
For camber plates that don't add to the stack height (and rob you of suspension travel), check out these:
I'm running similar ones on my WRX and have been pretty satisfied so far.
Monday, May 12, 2014 12:33 PM
I'm curious what the future plans are for power enhancement. I'm secretly (or not so secretly) hoping it will have something to do with the words "Crawford" and "turbo".
Monday, May 12, 2014 12:39 PM
Those plates are just like the KW ones. Not enough camber or caster adjustment. For power we are going to do the latest Nameless header and a different airbox with some custom tuning to max out our present blower. Next we are looking to do a larger blower and internally building the engine.
Monday, May 12, 2014 1:09 PM
What about the Ground Control top mount plates? It's kind of annoying that those specs are not available on on the GC website.
Can't wait to see the engine build articles!
Tuesday, May 13, 2014 3:34 AM
Really what we did has fine bump travel. The problem with the FR-S/BRZ is there isn't much vertical clearance in the wheelwell.
Tuesday, May 13, 2014 7:16 AM
Nice work! Are you going to do a write up on setting these shocks?
Thursday, May 15, 2014 4:51 AM
hope you guys do a write up on how to set up 3 ways coils. i just switched from a street coilover to a cusco zero3x similiar to these KW and my first track day with them blew my mind. however, i was on recommended settings by cusco and i only adjusted the low speed compressions to reduce some understeer. would love to make use of the other functions to get the most of the handling of my car. looking forward!
Monday, May 19, 2014 12:15 AM
Hey Mike, I had a question for you regarding the front setup. It looks to me like you might want to raise the front ride height (or get taller ball joints), because in the pic (page 3, bottom) the lower ball-joint boot is being stretched significantly. This leads me to think that the lower control arm is being held up too high into it's rotation with the current setup. It looks like the LCA is out of the preferable range which would then cause positive camber on compression. Check the pic below to see what I mean:
Monday, May 19, 2014 12:25 AM
If you read our prior installments, we have already installed ball joints with a much longer shank to correct the arm angle. Of course it still isn't optimal when you look at it from a narrow point of view but there are other issues to consider in the bigger picture. I want the lower CG of the current ride height and the only alternative to move the control arm is to make custom parts which I don't feel like doing at this point. I want to keep a forward sloping roll axis for more natural feeling and transitional balance. Correcting the arm location means significantly raising the front roil center. However, I want the front roll center to be lower than the rear and it is pretty complex to raise the rear roll center without causing other issues and without a lot of custom work or making the car not illegible for a lot of competition classes.. For now the compromises are fine how they are.
Monday, May 19, 2014 8:51 AM
That's cool. Engineering is always about picking the least-worst compromise. On this issue, you could also run some higher spring rates to limit travel as well. I'm glad to see you won't compromise on caster angles, as I think you can get a lot from positive caster on RWD platforms (I really like the dynamic alignment changes with steering angle, which can help you negate some of that positive camber you get on the Mac struts).
On another note, I've always wanted to do some experimentation with Ackerman steering, possibly seeing if I could gain something from Anti-Ackermann geometries like I see them do in Formula 1 nowadays. I would want to have a nice R-compound race rubber that likes higher slip angles before I do that (one reason I prefer taller sidewalls), and it would be nice to have some tire data to start with. Oh, and needing a new upright keeps me from doing this to factory cars.
Monday, May 19, 2014 1:54 PM
I have been experimenting with anti ackerman lately. On sedans it doesn't seem to work too well. The car has weird transitional handling. Reducing ackerman but not going into zero or anti might have some merit though. Seems to work well on FWD cars especially.
I didn't run higher spring rates because the car doesn't seem to need it which frankly surprises me considering the motion ratio is fairly high. The car has very little body motion. I try to run the softest springs possible to get the most mechanical grip as long as the body motion is well controlled.
Wednesday, May 21, 2014 5:21 AM
Speaking of interesting research with vehicles, have you seen the Mercedes-Benz F-400 Carving? I would've loved to work on that project!
Active camber control with active hydropneumatics with a new type of Active Body Control (ABC)
Thanks to the F 400 Carving’s active camber control, the cornering forces, compared with a contemporary car chassis, are up to 30 percent higher. Longitudinal forces are improved by up to 15 percent. Due to high lateral forces acting on the outer wheels, lateral acceleration is up to 28 percent higher than with sports cars built on conventional chassis technology.
Special Research Tires
The success of the F 400 Carving is attributable, in major part, to its tyres. These were developed specifically for this car and combine the advantages of car tyres with those of the motorcycle. The inner tyre has a rounded tread to allow best cornering behaviour; this tread also has an especially high coefficient of friction. When the wheels are tilted, the transmitted forces are particularly high. The outer shoulder of the tyre features a proven car tread and good straight-line stability. The tyre is mounted on a special rim with a diameter of 17 inches on the inside - the active cornering side, and an outer diameter of 19 inches.
Wednesday, April 22, 2015 2:47 PM
Mike, Any chance you have measurements on suspension pickup locations and geometry for the FRS? I have a BRZ and will be trying to copy cat bits of the FRS project over a longer period of time. I really dig your suspension and handling articles and in the mean time have been inspired to try to write a spreadsheet that calcs Roll center, Roll couple, and other static geometric values for my car throughout a given range of suspension travel. I just don't have space or equipment to accurately measure the control arm joint and strut mount locations or static arm angles.