have any of you ever hopped up a buick straight 8? and are there any performance parts for them?

Troy,

Buick straight-eights respond well to normal hot rodding. As one who's been out-run by more than one car, powered by a big ol' Buick, I'll vouch for that!

Increase the breathing with some port work, headers, better intake manifold,('41 Buick intakes with two carbs were popular when I was a kid, but may be difficult to find today) ignitions converted to 12V Petronix would give a great boost. Connecting one of these engines to a modern 5-speed would give awsome results, too. They are NOT high-reving engines, so plan to keep your RPM to a reasonable limit. (The crank will flex, if wound too tight)

You'll probably have to build your own intake/exhaust manifolds and/or modify the original ones. I doubt if you'll easily find any after market stuff like that today.

If I were you, I'd call or e-mail Tom Langdon, at Stovebolt Engine Parts Co. and get the straight info from him. Langdon's a wizard with anything that runs and won't steer you wrong. Tom has some fantastic progressive 2-barrel carburetors and the price is unbeatable. (I've got two of 'em on my 181 Mercruiser) I'll bet 3 of 'em on your Buick would make it honk!

Man, I hope you post some photos becasue I, for one, would love to see another hot inline Buick 8 on the road!

Troy, Check out Rides on this site, there's at least one Buick listed. There have been a few Buick 8 articles in the Club NL as well. Also, over the years I've seen many dual+ carb intakes for Buick '8's at swap meets. I'd search ebay and place some 'wanted' ads around.
Best of luck