US vs. Euro engine specs on a 450SE

[PMcG]

I've read that the US versions of the 450SE/SEL had less horsepower vs the European versions.  Are there any kits or modifications that can be done to do this, or some kind of tuning with the exhaust system that could do this?  Is it worth it?  Just looking for a few more ponies in the ride and acceleration, nothing crazy.  Any suggestions are welcome and greatly appreciated!

[ptashek]

The European 450 V8 post-1975 has 222HP, the US version has 185 I think, which is about the same as the euro 280 inline-six. Aside from all the smog stuff, they used different pistons as well.