anyone ever think of the US brake one piston metric racing calipers? the description is: U.S. Brake's aluminum brake calipers are machined from 6061 T-6 billet aluminum with an innovative internal interlock construction that locks together the caliper halves for increased rigidity and more consistent stopping performance with less brake pad taper. Stainless steel pistons are used for durability and to help reduce fluid temperatures. What you get is lower pedal effort, less pad wear and more consistent lap times that make this caliper the winner's choice!Oversize Metric GM Calipers
U.S. Brake also offers a series of racing brake calipers based on the GM Metric caliper. These oversized 2-3/4'' piston models give you over 20% more caliper clamping force than standard 2-1/2'' piston versions. 100% quality checked and tested. They're at 80 a piece and require no other mods.

 

Much better than the stock iron calipers. They are also lighter weight- less unsprung weight which is great. However, US Brake's metric caliper is not 'billet" their other high end units are.

Here are the basic equivilants from Wilwood. These also take the stock metric 154 GM pad on the NON-1LE brake package cars (the 10.5" rotor systems) and are even stonger and ligher than the USbrake units. They are just a bit more pricy @ $104.95ea.
http://www.wilwood.com/Products/Cali...-GMM/index.asp