Originally Posted by
GraphiteGhost

This sounds like a very good reason this went no-where. Could it be true the headers are like the exhaust when it comes to HP inprovements? Hmmmmm...

Possible, but unlikely.
I have this little nugget saved on my computer (see attached)... these are the VRP headers (basically the template Speedriven used) and they made serious ponies on the 32 motor. The Eurocharged headers made for the C32 were good power producers as well... but the plumbing won't fit the Crossfire/SLK firewall.