Project 914 3.6: Part 17

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Project 914 3.6: Part 17 1
Project 914 3.6: Part 17 2
Project 914 3.6: Part 17 3
Project 914 3.6: Part 17 4
Project 914 3.6: Part 17 5
Project 914 3.6: Part 17 6

We set ride height, toe (the difference in the distances between the front and back of tires on the same end of the car), camber (the angle of a wheel against perpendicular to ground; i.e. -1° means the tire leans into its fender at the top), and caster (the angle of the uppermost pivot point on the steering axis). Getting these adjustments right isn’t easy, as one adjustment can affect another. It’s harder when you’re trying to corner-balance, as these adjustments can also change the weight at a wheel that wasn’t being adjusted.

We started by setting the overall ride height a little lower than stock using a level on the door sill and a tape measure at the chassis. On our 914, the rear ride height can be adjusted by rotating a threaded collar on each of the aftermarket spring perches. Up front, as on all 914s with the factory torsion-bar suspension, ride height can be fine-tuned by turning an adjustment bolt at the end of each torsion bar.

While it was easy to raise and lower the 914 as desired, it was difficult to get its weight balanced correctly. Each time we made an adjustment, we’d push down on the bumpers and release a few times, letting the car settle on its suspension for accurate corner-weight readings. (This is where the ball-bearing plates helped.)

It took almost a full day before we were satisfied with the numbers, and it was still a crude job by professional standards! The payoff: 1) Our desired ride height, 2) corner-balance numbers that were where we wanted them to be, and 3) an alignment that was close — or at least close enough to leave fine-tuning to an alignment shop.

Graciously, the shop we went to allowed us to work directly with its alignment specialist. If you bring a 914 to the alignment shop, know that its rear camber setting is adjusted by inserting special shims of different thicknesses between the trailing arm and chassis; most shops won’t have them, so it’s a good idea to bring your own.

We placed two sacks of concrete on the driver’s seat to simulate my weight and disconnected the front anti-roll bar, as it can inhibit the suspension’s natural travel, a no-no during alignments. Once the car was aligned and balanced perfectly, we adjusted the drop links for the anti-roll bar so that the bolts could be inserted without using force; this avoids preloading the bar.

With the suspension properly aligned, we went on a short test run. The car understeered, but some adjustments to the anti-roll bar neutralized the car nicely and it could soon be pushed into corners at scary speeds. It didn’t take long to see that the fruit of all our labor is…a fun car!

Acceleration is strong, and the car handles like it receives nerve impulses rather than steering inputs! Several hours of driving revealed no oil leaks or problems and our 964 RS brakes never faded while halting this 2,237-pound 914. If anything, the system worked better as brake temperatures rose — so brake pads that warm up more quickly may be needed. Despite this first “joy ride,” I wasn’t ready to press Project 914 3.6 into regular service just yet. It was time for a better clear bra.

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