Being a Targa probably lessens the connection between the front and rear suspension I would think.

Thus, if you stiffen up the rear with a bigger sway bar it may not effect the front as much as on a coupe.

You took 50 lbs off the front of a car that stock had about 1200 lbs on it and lets say 25 lbs off the back that weighed about 1800 lbs. The seats are pretty much right over the ballance point of the car.

I used to run AutoX with a spare and track without.

Which Bilstein's? Some run standard in the front and sport in the rear. Both have a lot of front rebound I have heard.

Is the front set at max neg camber and caster?

What size tires and what is your fender height up front?

Because this is a very old box now and it is relatively well known what works and what doesn't work.

By the way, setting the car to the US ride height and alignment settings isn't the answer.

Scott

strlj,

If you are getting understeer in your 911 with more negative camber you are not driving hard enough. You need to learn the special techniques for driving a 911. You need to transfer weight to the front to get the front tires loaded so that they have more grip. This makes turn-in quicker. In steady-state cornering, the negative camber helps even out tire wear and makes the tire present a better contact patch (flatter) to the road.

Cars like BMWs will respond to steering input a bit quicker at first and when you are not really "on it", but then start to plow when pushed harder.

Automotive Engineers dial-in understeer using toe-in, less front camber, front-biased roll stiffness, and wider rear tires.

To the OP:

Yes, having a Targa will make using anti-sway bars less effective. In that case, a wider front track or more caster (for more camber in a turn) would be the most effective solutions, I suspect. Or a roll cage to stiffen the car.

There are many opinions about suspension set-up; despite the excellent information above the one that matters most is your own. Start with a good baseline: new tires and new Bilstein HD's made a huge difference for me. Then I took the advice of Rich at Jerry Woods and bought a good air compressor, hose reel, and a racing pressure gauge with bleed valve, and started playing with tire pressures. I have dialed in a lot more front stiffness at my current favorite setting of 36 psi front/38 psi rear for 205/55-16 and 225/50-16 Kumho Ecasta SPT's. This has made my car beautifully neutral.

I also strongly agree with Flieger that the next step is to pay careful attention to weight-transfer. My car really responds to the old "slow in/fast out" technique of getting a bit hard into the brakes to load up the front tires, trail-braking into the corner, and then letting the rear end settle before getting into the throttle. The weight-transfer characteristics of a rear-engine car mean you can (and have to) brake pretty hard to get the front end to bite; once you've completed turning you can take advantage of the traction created by the engine out back to get hard on the throttle when exiting a turn. Of course, the radius of the turn and mechanical grip of the tires with the pavement also need to be factored in to the equation. Every corner (and every driver) is a bit different. My car would probably be pretty tail-happy on a steady-state skidpad, but that's not where I drive!

I found my old 1975 911 over-steered when pushed real hard into a corner. Under moderate/lighter driving and cornering it did tend to plow.

But then I bought my 84 factory widebody and what a completely different cornering experience! This widebody car when pushed hard in the corners simply 4 wheel slides. It tends to sort of do neither under or over steer.

Can anyone explain why the widebody cars are so different?

More grip all around and more rear tire staggar. That is my guess.

Your not driving it hard enough.

Wide bodies are no different - just have higher grip in normal cornering, especially with the NA motor. With sticky rear tires, you put down 350 hp early in a turn, the front end will go plowing off faster than you can say 'hay bale'.

Understanding and dealing with the dynamics of any venicle when you are changing its direction of travel, all boils down to the seat of the pants.

One person may drive a 911 for the first time and very quickly sense that there is a weight over the rear wheels that causes the car to behave entirely different than cars that have that weight over the front wheels.

A front engined car, if looked at as if it were a dart on wheels, is heavy up front, just as a dart is.

A rear engined car is like a dart also - but the dart is flying through the air backwards. Throw a dart backwards and its back end will swap ends - as will a 911, if you let it.

And the actions you take to correct a sliding 911 generally run counter to those one reflexively takes to correct a front engined car.

Some are confused at first, then read up on the topic, practice and learn to really drive a 911.

Others may immediately sense the weight shift to the rear, the seats of their pants will tell them what is happening and they will take the proper actions without thinking about it, kinda like a skier who doesn't consciously analyze every mogul rushing towards them, they just ski them.

Good race drivers have that natural seat of the pants ability to sense what a car is inclined to do and what to do about it. A lot of others seem to have very little.

I have heard this more than a few times.


Widening the track has the same basic effect as lowering a car. It improves the relationship between the center of gravity and tire contact patch. Learned this from Chuck at Eliphant Racing.

The Turbo Look also has some fun changes over the 911 as it has the same goodies except for turbo tie rods that the 930 had.

Both the front and rear seem to have different geometry such that it will roll less if the same spring rate is used on it compared to a 911. Learned this from exchanging thoughts with Fleiger and a couple of others. However, it is more my opinion that some of the others.

Thus, you had two things working for you.

This does not even count increasing tire sizes.

Fun stuff!

The 930 has some geometry improvements front and rear compared to a regular 911 that have an impact on handling above and beyond the track and tire size differences. The front has some anti-dive and higher roll center while the rear gains camber faster as the suspension compresses and has a higher roll center. The rear may have some more anti-squat but that is open to debate.

Scott