Project 718 Cayman T: Part 19 – TracTive Track Line Coilovers and Rennline Transmission Mounts

I asked the team at Paradox Performance to set the ride height similar to the factory SPASM specification to keep the car street friendly.

For the alignment, I’m taking a little bit of a swing at the specs as I’m not positive on how the new spring rates will shift the dynamics with respect to the alignment. I asked for the front caster only to be backed off a few mm to avoid the front inner fender liner rub and left the front camber at -3.0. The rear camber was increased to -3.0 from the previous -2.5; I was showing significantly more outside shoulder wear on the rear with the factory springs and dampers compared to the fronts. Coincidentally, on my old S2000, I ended up with around -2.8 degrees of camber front and rear. The front toe is set to 0 and the rear is toe-in 2mm, same as before.

Before dropping the car off at Paradox Performance, I loaded up new values in the shock calibration tables in the DSC that would work for both the factory dampers and the new Tractives. The mA range for the factory dampers is around 1700mA-100mA and the Tractives go from 2000mA-600mA. So, I set the range from 1600mA-600mA. Joey, the owner of Paradox Performance, did a check-out drive to make sure the installation by his team was to his satisfaction and he noted the front-end felt like it needed more rebound.

Based on Joey’s feedback, I stiffened up the front compared to the rear. I used all the exact same values in the DSC maps as before except for adjusting the Shock Calibration values. For Normal mode, I set the front range to 1900mA-900mA and the rears to 2000mA-1000mA. In Sport mode, the fronts are 1600mA-600mA and the rears are 1700mA-700mA.

I’ve only driven on the street so far, but my initial impressions are very positive. As expected, turn-in and lateral transitions happen much more quickly now with less roll; about double the factory spring rates will do that. What’s fantastic is that the car is still great on the street from a feel perspective. One of the selling points of the Tractive DDA dampers is the reaction speed of the dampers at 6-10 milliseconds compared to the factory Porsche dampers in the 100-150 millisecond range. I can tell you that the Tractive setup rides smoother over all the little bumps compared to the factory dampers. There is this one 40mph sweeper that I take on the way to work that is quite bumpy. The new Tractive setup is noticeably smoother and more stable driving through the bumpy corner compared to stock despite the much higher spring rates. And that was driving using Normal mode. Sport mode seems really unnecessary now except for driving on the smoothest roads. I’m excited to get this thing out on the track and put it in Sport. As for the transmission mounts with the softest durometer yellow inserts, I think they feel just a bit stiffer than the factory PADM mounts set to their stiffest; maybe around 10%-20% stiffer. I think the car is a little bit buzzier over 4,000 rpms and I can feel some vibrations through the center tunnel. The difference in NVH with the Rennline transmission mounts compared to the factory PADM mounts is much less pronounced compared to when I put the Hasport engine mounts in the S2000; there was no mistaking the S2000 had non-factory engine mounts. I’ve gone back and forth in my head if I should have used the medium stiffness blue mounts to get a noticeable difference, but I’m content with the stiffness with the softest yellow inserts. If you want a ‘dumb’ transmission mount after your PADM fails, and it will fail, these Rennline mounts with the yellow inserts basically feel only a bit stiffer than PADM at full stiff. There is some extra noise that makes it into the car with one of those noises sounding like straight-cut gears when cruising at highway speeds, but it’s quite low dB. Tire noise or just turning up the stereo a bit will easily drown out the extra noise from the transmission mounts while cruising. I didn’t even notice this straight-cut gear-like sound until I went on the highway and it was barely noticeable. Of course, you can go even stiffer with the mounts with the blue and red inserts if you want to. Just don’t forget to the extra washers to put under the bolt heads.

A concern I had in going with the stiffer springs was causing the car to be too bumpy during highway driving. My old S2000 on KW Clubsports with 12kg/mm front and 10kg/mm rear spring rates was so bumpy driving down the 405 around Los Angeles, I couldn’t drink out of a cup as it would spill everywhere. The 718 Cayman with the Tractives and the spring rates I selected are just as smooth as stock. This was my hope in sticking with spring rates close to the 718 GT4 factory values. The one downside of the Tractive Track Line setup is a fair amount of noises going over bumps. The spherical bearings in the adjustable camber plates are the likely culprit in transmitting all the new noises. For me, the extra noises are no big deal. The gain in chassis responsiveness, the improved cornering stability, and better ride quality I’ve experience on the street so far have met all of my goals. Make no mistake, the TracTives and the Rennline transmission mounts have solidly shifted the bias of the car to the track side of the balance due to all the extra noises. No typical person would ride in the car and think it came like this from the factory. Now I need to get on the track to also verify the improved tire wear and extra grip from better utilization of the tires.

With the new coilovers installed, the car is ready for the track again. To fill the track itch while my car was not in track-capable condition, I drove the GT4 and 992.2 GT3 at the Porsche Experience Center Los Angeles. Anyone who is an advanced driver, I say skip the GT4 and just go straight to the GT3. The latest generation GT3 I drove had rear wheel steering and the shorter gearing. I’d say two features make the 992.2 GT3 really stand out: the engine and the steering. The throttle response of the GT3 is extremely precise and fast; it rivals an electric motor. The engine will dole out exactly the torque you demand based on throttle position nearly instantaneously. The PECLA has a wet skidpad and a low-friction handling course for drifting. I’ve driven a half-dozen cars on the wet skidpad and had never held a drift more than ¾ of the way around. With this GT3 and the very precise and quick throttle control, for the first time, I was able to keep a drift around the skidpad. Then we went on the low-friction handling course and I was able to drift and link a few corners together, looking like I’d done it before. Trust me, I never have. The other standout characteristic of the 992.2 GT3 is the very quick steering. It has both a quicker steering rack and the rear wheel steering. The steering is so quick, I knocked over a cone the first time around the auto-x course. Oh, one other thing, the tires never went off on the GT3 over the course of the hour I drove it. That double control arm front suspension is pretty nice. The GT4, on the factory alignment, I cooked the front tires like I did my first time out in my 718 on the factory alignment. I drove the 991.2 GT3 at PECLA some years back and that car was really good. The 992.2 GT3 is really REALLY good. The quick steering combined with the front-end grip is something else.

I sold my trusty 2005 Honda CBR 600RR three years ago to make space for the Cayman and I hadn’t been on track on a bike in a dozen years. I decided to scratch that itch too and hit up the California Superbike School. It had been nineteen years since I last did the school, so I repeated the Level 1 class. Last time, the school used Kawasaki ZX-6Rs. Now, the bikes are BMW S 1000 RRs. I don’t know what BMW did, but this liter bike flicks side-to-side as quickly as my 600cc CBR. Modern bikes have all the modern electronics with drive modes, ABS, and traction control. And I’m pretty sure I felt wheelie control too; I was full-throttle in third gear and I swear I felt the front wheel wanting to come up at around 9000-10000 rpm. The S 1000 RR pulls as hard in third gear as my old CBR 600R pulled in first gear. If you ride, I highly recommend this school if you haven’t already done it.

Time to get the Cayman back on track and see how the new suspension package works with the wheel and tire package.