Drag Racer3

Not a bad drag racing game.

It lets you customize you customize your car, for performance (ignition, turbo, exhaust, computer, etc...). Then lets you race for pink slips, wager, tournament, etc...

The engine will even blow up if you over rev it or if the boost gets too high.

In the end it's only drag racing, but for a free online game it's not bad.

http://www.addictinggames.com/dragracerv3.html