Project Porsche 987.2 Cayman S: Getting the Suspension Together! Part 2

Chris checks the toe using a toe bar on the scribed line.

The toe is set quickly by spinning the adjuster on the Tarett toe link.  With the Tarett parts, this is very fast and easy, you simply loosen the pinch bolts and turn!  We set the rear toe at 1/8″ in total.

Chris used the sway bar links adjustability to take all the preload out of the rear bar.  Following the advice of some successful Porsche racers, we set the rear bar at full soft for now.

Chris checks the front camber.

By turning the wheel from side to side and measuring the camber difference, the caster can be determined.

The 987 has a narrow front track compared to the front. We wanted to reduce this and get the front track as wide as possible. We used Taretts thick adjusting shims to extend the lower control arms about a half-inch, widening the track an inch from the arms and another inch or so with the wheels and tires. This also helps fill the wheel well nicely.

7 comments

  1. Great as usual, curious to see how this does on the track. I run the atx-20 on my wrx. At three pounds and change it’s great. My car starts better with this over the factory battery, however it sits on a battery tender. While I haven’t had to use the restart feature, it’s another reason to like this battery.

    Have you thought about this?

    https://www.autoquestcars.com/custom-09

    1. I would be careful and run a battery tender that is for lithum batteries only! A well-known friend of ours blew up his car and almost burned down his shop because he used the wrong trickle charger!

      My opinion of this kit is that the upper links are way too short and you will have too much camber gain for rear-driven wheels. The short links can also contribute to jacking and lots of roll center and instant center migration. The short links will also cause side scrub which can contribute to instability on split mu surfaces and under certain load conditions. Lastly, the anti-squat percentage is really high and that can contribute to a loss of traction under corner exit as well as wheel hop. The Cayman/Boxter chassis has wheel hop as a known issue and they exhibit a high degree of anti.

      I may be working with a well-known Porsche suspension parts company next year to develop my own solution to these issues on the 987 chassis which if it comes to fruition will be much better than this! At least in my own opinion.

      1. Oh yeah, I use a lipo specific one. Not making that mistake. Lipo fires are for Richard Hammond anyways.

        Competition is a wonderful thing, love to see what is born!

  2. I enjoyed the 3 pages on the alignment and all of the other 987.2 Cayman content. Can you write more about setting the anti squat / dive front and rear? Also, about how the team measured the bump steer? All of the specs? Have you run the car on track yet? How did it feel, any adjustments?

    I have a 987.2 will all of the Tarett parts that your car has and have not been able to find a shop around Atlanta that will got to this level of detail.

    Thank you

    1. We are waiting for softer front springs right now. I want to go down to 10 kg and KW is backordered. The balance of the car is ok but there is a minor pitch issue I think is frequency related so I want to go softer spring wise in the front and up in the front bar. As far as bump steer, Porsche is pretty well designed and there isn’t much, but if you mess with the roll center you need to move the tie rods by close to the same about or you will get bumpsteer. Basically, if you want to measure it you take off the springs and move the car up and down and measure toe every inch and plot it. However, we did this and the toe curve on these cars is pretty good. I would talk to my local PCA or POC racers and they probably know a prep shop that can properly align and corner balance your car. The specs we gave in the article were pretty aggressive like what cup cars run so they would kill your tire on the street if your car is a daily. To make it simple to reduce anti we shimmed the front trailing arm pivot down, The 987 has a lot in the rear.

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