Because LS2 engines have a 90mm drive by wire throttle body, and LS6 intakes are a 75mm.
Although the LS6 is a much better intake, Im assuming they dont want to pay for another drive by wire throttle body, thats smaller. Im usure of the compatibility of older 75mm DBW TBS with the new 90mm ones also, that could be another factor.
__________________  Quote: |
Originally Posted by John Lingenfelter The world's best cam combined with a poor set of heads will produce an engine that's a dog. But bolt on a set of great heads even with a poor cam, and that engine will still make great power. | | 
jw 
