Corner Balancing for all you Road Course people

[Stephen31201]

^^^

 

[Vorshlag-Fair]

I am looking for somewhere to take my car near Greensboro, NC to have it corner balanced. I know that you want to cross balance so that LF+RR = RF+LR. My question is do you try to move the weight to the rear as much as possible while obtaining 50% cross weight, or is where the weight ends up just a byproduct of trying to get the corners at 50% for each diagonal?

That isn't how cross-weight balancing goes... you can't move weight front to back by changing corner heights, just from one cross to the other. To change weight bias front to rear (or side to side) you will have to physically MOVE something of mass.

We normally post pictures of cars we have weighed without the driver or fuel (or "trunk junk"), and you can calculate front to rear bias easily this way. But for a corner balance you have to:

1. Have the driver in the driver's seat (or a similar amount of ballast)
2. Disconnect the front and rear swaybars (to keep the swaybar from adding preload on that axle)
3. Then you adjust the ride heights at various corners to get the two crosses to equal the same, within about 0.2%

We don't normally take a picture after cross weight balancing with the driver in the car - most folks don't want to see their own body weight on display.

 

[Stephen31201]

How big of a difference is it in handling Terry? I am just trying to spend the funds wisely and try to get the most bang for the buck.

 

[modernbeat]

How big of a difference is it in handling Terry? I am just trying to spend the funds wisely and try to get the most bang for the buck.

The stiffer the spring rates, bushing durometers and tire sidewalls, the more important corner balancing is.

On a car like our Big Red, it made a difference.

 

[Stephen31201]

Gotcha. Ill put scales on my list of wants, and after all safety equipment is purchased I may end up that route. I'm trying to play a rich mans game on a working mans budget.

 

[modernbeat]

Stephen, even though the price of entry level scales has fallen in the last decade, they are still relatively expensive. Paying a shop to do it is also expensive, but you can rely on their recommendations. If you plan on buying a set and are on a budget I'd get a couple of other friends together and go thirds on the set. More than three it gets a little hard to manage.

 

[Stephen31201]

That's a really good idea! I never thought about it that way. $250-300 a piece would be a breeze. Any people reading this and live near Greensboro or VIR let me know. It would be great to have a set in order to re-balance after spring swaps.

 

[Boone]

I'm in High Point, and I get the impression you're a little more hard core than I am. If the setup were available, I would help you offset your costs by throwing cash your way for use of the scales.

As is usually the case, I'm sure I'll get more interested in fine tuning as a learn more about the vehicle dynamics down the road. But, for the time being, I'm just curious about some static weights.

 

[2013DIBGT]

One thing I found interesting while reading the Boss 302S owners manual was that Ford Motorsport recommends doing corner balancing with a FULL tank of gas due to the cars saddle bag gas tanks. It was mentioned that a good side/side balance could be a challenge if the tanks are not full since an uneven ammount of fuel could reside in one saddle bag more then the other resulting in an uneven distribution of weight.

I guess if one doesn't have a way to remove all the fuel beforehand then taking this other route may be the next best option.

In hindsight, I didn't use either method and instead used a half tank of gas and my body weight as a ballast. Maybe next time I will try one these other approaches

 

[Stephen31201]

I'm not really sure of how Ford setup the tanks for the Mustang. I know there is a cross over tube of some sort that attaches to the pump, but I don't know much more than that. I have a friend that is interested so I may do half's with him on the scales. Hopefully we could recoop some of the cost by doing like Boone mentioned and let locals come over and pay to sue them.