uklad

Decided to do a little experimentation with the weight distribution, centre of gravity and polar moment of inertia of my heavily modified autocross car. The car weight has been reduced by roughly 400lbs leaving an insane front to rear weight dist of 75:25. Monumental understeer, terrible instability under hard braking and horrific wet weather performance (rear tyres aquaplaning) were the outcome. After a few measurements, it was time to grab a bucket and shovel and get busy.
Basically what i've done is add 90lbs of ballast low and far back on the vehicle in an attempt to move the the C of G back and decrease the loading on the front wheels. I wanted the ballast behind the rear axle to maximise the effect on the front wheels. (Sure enough the wheel arch gap over the front wheels increased as expected)
Any way, initial test drive felt very positive in many respects with turn in response sensationally better. Tomorrow is the first race of the season so i'm anxious to see what the clock tells me.
By the way it sure does look like **** does'nt it! Think a coat of black masonry paint might be in order!!!!

<img src="http://pictureposter.audiworld.com/128975/dsc_0131.jpg">
<img src="http://pictureposter.audiworld.com/128975/dsc_0133.jpg">

J. Patterson

So, Maybe the lead ballast behind our TT bumpers makes sense after all! Interesting post.

AxeYrCat

Are you not concerned about the concrete cracking?


And I think it looks awesome back there like that... 'Is that guy driving around with pavers attached to his car?!'

TTschwing

uklad has pointed out the perils of rear weight reduction at the expense of handling and balance....too many here just don't understand the interaction..

The only way to get closer to that magical 50/50 weight distribution is to either move weight from the front to the rear, or add weight to the rear as he has here.....
(or buy a Corvette....:-))

TT_Nuge

buy a BMW. I remember first shopping for my BMW and they were throwing around numbers like 50.4%/49.6% and the like. But obviously different beasts.

TTschwing

It's almost impossible to bring a front driver into balance if it wasn't engineered that way from the git go...

mad scientist

after driving an FWD with one, I am a believer.

GorTT

(...except for that horsepower thing....). Actually I've been thinking of making a mold of my spare-well and cast a few pounds of lead for it - the fwd well sits lower than a Q, of course.