I believe there is, but they're designed for racing, not sure how well it would work on the street. You could contact Esslinger engineering, they even show them in pics on their website but say thay don't sell heads over the Internet, so you have to talk to them by phone:
http://www.esslingeracing.com/
Here's another interesting solution:
http://www.merkurtech.com/merkurtech...es/item045.php