Looking at the previous picture, I was like…. Man, the front of the car is low when the suspension is loaded up. I took a peek underneath, and sure enough, part of the air deflector was worn away. Sorry about the air deflector being out of focus.
The AP Racing brakes held up awesomely. The first time David touched the brakes pulling up to the staging lane, the car stopped pretty hard as he was use to the stock sized brakes on his S2000 requiring higher pedal force. Andres took the Cayman out for a few laps and he didn’t realize I was running Ferodo DS2500 street pads and assumed I was on track pads; he runs track pads on his ND Miata for track days. So, on the out lap, he was tapping the brakes to get some heat into the pads, but realized they were good to go. The massive thermal capacity of the AP Racing big brake kit setup allows me to run a street pad on the track at my horsepower levels. This is the same philosophy I took with the S2000 back in the day with the StopTech setup.
With spherical everything in the E-Motion Engineering components, steering and chassis feel is very transparent and direct. I can feel what the front tires are doing through the steering wheel. When the rear was starting to slide out, the feedback through the butt and steering wheel was unfiltered and immediate allowing me to correct more quickly. Increasing the caster from the factory setting increases the effort to turn the steering wheel off-center and I personally like the extra bit of heft required. The increased track width and wheelbase allowed by the E-Motion suspension components added to the vehicle stability in the rapid transitions.
On the street, you do get more NVH transmitted from the road into the chassis because all the rubber was removed from most of the suspension joints. But, with my DSC settings in Normal mode, the ride is still plenty smooth enough for Bandit to take a nap going down the rough 405; I did adjust the default rate down to 7.5 from my initial setting of 10.0 in Normal mode. I doubt he would have been able to sleep in the S2000. I had the S2000 so stiff, I couldn’t drink out of a cup going down the 405 as the car was bouncing too much.
A few days after Streets of Willow, I took the car to the Porsche Experience Center Los Angeles. My instructor was in the red 718 Cayman GTS with the 394hp, 4.0L, naturally aspirated, flat-6 engine. On the straights, he wasn’t pulling on me much, which is a good indicator of the power of the Raggdoll Motorsport RENNEN turbo upgrade with a pro-tune from Alex at Stratified Auto; this is only the second tune iteration for the bigger turbo on 91 octane and it still had more adjustments to go. When I did PECLA last year, I had only owned the car a couple months and I didn’t have a good feel for where the corners of the car were. The apexes on the track at PECLA have rumble strips that are about a foot wide and I wasn’t even touching them. With a year under my belt in this car, I’m more in-tune with where the tires are located and I was driving over the rumble strips every time. I feel like I’m still about six inches off of the apex whereas I could place the S2000 within about two inches. Oh yeah, I was curious what my heart rate was while driving on track; I averaged around 120 bpm which is about double my resting heart rate.
After doing a chunk of laps, my instructor radioed that his brakes were starting to get a little soft. No such issues with my AP Racing setup with the front brakes at 372mm diameter vs the OEM GTS setup at 350mm diameter. I will add that once the DS2500 brake pads get a lot of heat in them, they squeal a bit at light pedal effort. We did a few cool-down laps and hit up the auto-x course where I did a handful of runs. With my current DSC tuning, I feel the rear is right at the edge of staying inline during the slalom. If I go do an auto-x, I’ll create a dedicated auto-x tune that biases a bit more towards understeer in order to stay in shape in slaloms.
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.