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Originally Posted by Randy Chase

To some extent. I have removed weight in a previous race car and removing a front mounted battery (midengined car) and relocating it caused the front end to have no grip (to my surprise).

I should have said that it will rotate easier assuming there is enough grip. Like I said before there are many, many factors of setup that all add up to the dynamic balance of a car. Weight bias is one of them. If moving the CG rearwards lost you some front end grip, I humbly suggest your setup was dialed in for optimum grip with the battery up front. You changed something and it wasn't optimum any more. I'll bet with a simple adjustment somewhere else you would have got your grip back and - at least mass-wise - would have resulted in a car that turned better.

Look at something like an Audi A4. Engine actually forward of the front axle line. High front/rear weight bias. Understeers like crazy at the limit according to the articles I've read. Moving weight forward does not inherently provide more grip in the front.

Actually to be more clear I should say it like this: Weight in the front does provide more mechanical grip in the front, but it also means you've got more mass to move up there. So there are two factors working against each other. Probably in some circumstances the extra mechanical grip will win out, and in other circumstances the extra mass trying to go straight will win out. Setup of the other factors can help control those circumstances.

The Elise/Exige is also very rear weight biased. Dare I claim that my Exige understeers a lot less than any of the cars I've ever owned with a front weight bias? Would nobody believe me? The claim was made that a high rear weight bias inherently results in understeer. I disagree. If it's true somebody needs to tell the Porsche 911 engineers!

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