well a cam for a blower is generally different then a cam for an NA application. Generally you spread the lobe centers apart a little more for the blower cam. You probably would get good gains with that cam and blower, but with a different grind could get better. I don't know about any 300 hp. Since it's stock at 210 SC, and I'm not sure what they dyno at with the smaller pulley, I'd still say you're going to top out around 250 or 260. A lot of it will be top end too, as that's where the blower makes most of it's boost and where the cams will make a HUGE difference.

If you are familiar with a pushrod engine, the lifter is equivelant to a rocker arm. Basicly you have the lobes on the cam which as the cam rotates pushes the valve open and then allows it to close. A lifter is a pivot arm that the lobe of the cam pushes against. As it pushes one end of the lifter up, the other end goes down and forces the valve open. There is friction involved here and the lifters and cam tend to wear together to the point where a lifter is matched to a lobe. Putting a new cam in would be putting fresh lobes up against a unique wear pattern on the lifter and usually causes excess slop in the vlave train. So when changing a cam that has had a chance to wear, you usually want new lifters.

There are two reasons headers won't be street legal. The first one is that a lot won't weld in O2 sensor bungs, so on engines running a pair of O2's per bank, on the stock exhaust system, the stock emmissions wouldn't work. You can have the bungs welded in and run everything fine, but since that's not part of the part....it's not "street legal" You can still pass inspection and emmissions tho. The other reason is that they don't go through the expense and trouble of getting the headers CARB certified. CARB certification is a royal pain and an even larger expense to the manufacturer, so it's often times easier to just say it's for "off road use only" and bypass the whole matter.

If you want to learn more about automotive stuff, the best place you can start is www.howstuffworks.com

They have great articles with animated illiustrations and do a great job of describing how stuff works. For more technical stuff just google around. Look up things like "cam tuning" or "exhaust scavenging". There is a lot of information if you just look for it.

I still don't understand why the X's red line so low. For an OHC engine it should be up near 7000 or above. Heck, my pushrod motor red lines at 5700, can survive up to 6200 and with some upgraded parts will hit 6800 to 7000 without breaking a sweat.