The stock suspension of the 718 Cayman does not have enough adjustment range for serious road course track work. You can’t get enough negative camber in order to prevent destroying the outside edges of the tires. So, after the first three track days with significant wear of the shoulder of the tires, I said I wouldn’t do another track day until I modified the suspension to get the camber it needed. A proper alignment was the last missing piece for getting the car to dual street car and track car greatness state. While I was going to be in there, I wanted to go spherical bearing wherever I could. I got a hold of E-Motion Engineering and dropped my car off.
The primary goal was to get suspension components to be able to run up to -3.0 camber in order to get better performance and life out of the tires; I would note that dedicated track 718s will run upwards of -4.0 camber. Camber plates and tie-rods would likely achieve that goal if one wanted to go a budget route. However, I had full spherical bearing suspension components on Project S2000 and I knew I wanted that on the Cayman too. Therefore, I told E-Motion Engineering I wanted everything they offered for the 718 Cayman with spherical bearings. There’s more to the E-Motion parts than just getting rid of the rubber and allowing a track-oriented alignment.
These are the factory front and rear control arms along with the rear toe-link. There’s a lot of rubber in the mounting points.
There’s a lot of voids in the rubber at this joint. The tension arms in the suspension attach to the control arms at this joint. The rubber here can allow toe and caster changes under heavy loading and bumps.
The rubber bushings here also allow the suspension geometry to deviate under hard loading.
I typically like to install everything myself, but I asked the team at E-Motion to do this install. I didn’t have the tools nor knowledge of this platform, plus I needed an alignment afterwards. E-Motion paint-marked everything to indicate parts were torqued to spec during installation. These marks are great to for a quick visual check to make sure nothing has slipped after track use. There are a number of features of the E-Motion front lower control arm setup that I like. A primary feature I like is the use of a solid bushing in the control arm where the front tension arm attaches. Many other front lower control arms use a rotating puck here in order to adjust the caster. I see that as an area for variance in adjustment along with a component that can possibly slip out of alignment. For my alignment, I asked E-Motion to set the front caster at 9.5 degrees; the factory setting is around 8.0 degrees. Going with the E-Motion front lower control arms does require their front tensions arms whereas the designs with the rotating puck can reuse the factory front tension arms.
11 comments
Great update. Any plans to go to a dedicated DOT-at wheel/tire set up for the track?
I’m planning on 19″ wheels and RE-71s (245/275 vs current 235/265) after I wear out these tires. Save a little mass. With the stock springs, I don’t think they can handle that much more grip.
The rear toe arms on your car are the non-GT4 Tarett ones. They’re just a different length than the GT4 ones due to different subframe and hubs. Your front tie rods look like Emotion, slightly different design.
Just did a very similar setup on my T with Dundon front tension arms (shims as well) and Tarett control arms. Curious how Emotion got the factory rear tension arms to work the their puck, which only has a center hole. I had to use the eccentric hole due to the factory tension arm not having enough machined off the LCA mount to avoid interfering with the edge of the puck in the center position. Wonder if they just machined it further out to fit. Trying to avoid either throwing off the toe curve with the eccentric or losing the T brake duct by going to an aftermarket rear tension arms.
Also didnt realize that the narrow 991 GT3 style LCA inners worked on our cars.
Cheers – always enjoy hearing about your project
I added some pictures for you and the parts list for the car. The front tie rods are E-motion parts. They don’t make their own rear toe links because there’s no real reason too with the various options already available. I had bought TPC rear toe links for the 718 Cayman, but they didn’t fit as the E-motion setup required GT4 compatible parts. So E-motion ordered up what I believe are the Tarrett parts.
Thanks so much for the photos! Finally got the car back together (didn’t realize that all the subframe bolts for the front sway bar were torque to yield, so took a bit to get new ones).
Seeing the sharpie mark on your trailing arm really helped. That was marking how far out they had to remove material from the inside of the flange, which was machined for the narrow metal interface on the rubber bushing vs the full width on the aftermarket solid pucks. Took a Dremel with a fine sanding bit and got a pretty nice result.
I had the pleasure of driving Khiem’s 718 at Streets of Willow CW (thanks Khiem!). Although I have limited seat time in Porsches, I agree with his comments on it being a well balanced setup for both track and street use. I’m excited to see the ride difference with the E-Motion Engineering spherical bearings and links installed! Any plans on increasing spring or roll bar stiffness? Looking forward to another track day soon!
Maybe coilovers…..
Hi Khiem,
Curious if you are considering upgraded Anti-Sway bars for this project or not. I have a GTS that came with single hole non adjustable bars and considering a second hand set from a GT4 that have three holes so I can adjust the bias front or rear. Still working on how thick my current ones are vs the GT4 bar.
Good job on the project so far, I love the tech and reading all of the articles. Looking forward to the next installment
Jeremy
I’m content with factory bars. I would typically use adjustable bars to tweak the handling balance, but I can do that effectively with the DSC.
Update: on my GTS I have now installed a set of used GT4 swaybars.
On the track I used to have to wait for the car to take a set into the corner, now it can just turn.
Still playing with the multiple holes of adjustment and feeling how the balance changes front to rear.
The front for our non GT4 cars require a shorter end link, the rears links work as they are.
I also have the DSC but don’t yet know how to go about making these changes as the DSC is based on velocity tables.
Thanks for the update! You can adjust the low speed rebound settings in the DSC to tweak the handling balance.
Agree on the stock suspension, especially in normal mode, needing to wait for the car to take a set. This is really evident in a slalom. I’m content enough with my DSC tuning for sport mode in that regard.