Phokaioglaukos

I've read here that one should corner balance with a half tank of gas and a weight in the seats as you'll have on the track. That makes sense, a half tank of gas will split the difference between full and empty for balance (except that 3/4 tank might be a better "average" for street driving). The Porsche manual, though, says to set the ride height with the tank full, and that makes sense as having maximum weight in the car will compress the suspension more than a half tank--you wouldn't want to set the height and then add gas and end up too low.

So, what do you do and recommend? Tank half full, full or something else?

Bob Rouleau

Half a tank and the driver or equivalent weight in the driver's seat. You do this after having set the ride height correctly as per the book. The change in ride height needed to corner balance is quite small. Unless you track the car there is no need to corner balance.

Rgds,

Viken

FWIW, Porsche recommends a full tank of gas and no driver:

Bob Rouleau

Viken I agree. The procedure you pasted is for setting the ride height. One should do that first, then do the corner balance with a half tank of fuel and the driver in his seat.

Best,

Viken

Bob, I don't disagree with you, but the factory manual does state that ride height, alignment and corner balancing be done in the above manner (full tank and no driver). Just posting what the manual says.

Bob Rouleau

Viken,

I saw nothing in the posting about corner balance. Since the driver weighs a lot, I cannot imagine doing a corner balance without his weight in place. All the instructions I have ever seen have the driver or equivalent weight in place. My 180 lbs on the left side has to affect the corner weight. You planning on being out this way this summer? We have a DE right after the F1 race...
Best,

Viken

Again, I don't disagree with you and I think the driver's weight in the seat is a good idea for corner balancing. But, Porsche does not suggest that.



I am still planning the rest of the year. I'll let you know once decisions are made.

Phokaioglaukos

Bob, do you set the height with a full tank and no driver, then siphon out half the tank and put a weight in the driver seat to corner balance?

Viken, what do you do?

Viken

Nothing. I have not done any corner balancing on my car. Just some custom alignment settings. However, with all my previous 911's, the corner balancing was always done with a full tank of gas and the equivalent of my weight in the driver's seat.

JasonAndreas

Is the DE on Île Ste-Hélène???

Bob Rouleau

Pho - I do it in two steps set the ride height as per the book (above) and then bring the car back for the corner balance with as close to a half tank as I can.

Jason - no the DE is at Le Circuit Mont Tremblant. A nicer circuit than the Grand Prix in my opinion. It's about 75 miles North of Montreal in the middle of a 4 seasons resort.

Best,

enthusiast

I don't think Porsche AG will address corner balancing for a street model due to legal issues. It implies "racing" use.

Viken

Then, why are they giving full instructions on corner balancing in their workshop manuals?

Bob Rouleau

Perhaps because corners on the autobahn at 240 KPH require a betteer balanced car?

enthusiast

Viken

In what you posted from the manual I see the instructions for 'lateral' weight balancing but not 'longtitudinal' front to rear (other than advising one to keep the front to rear ride height difference within specs). So, I stand corrected in that they are doing a partial corner balance.

I still don't understand their emphasis on lateral balance when they don't place any weight in the driver's position?

The GT3 Cup manual states, "Car to be measured with 1/2 Tank of fuel and 75 kg in the drivers seat. Joint and wheel bearing play checked (wheel bearing play can not be adjusted). Front and rear tyre pressure set to 2,0 bar."