| I think you're on the right track with understanding that the air is tuned. In other words, you can't just have a cam that works at real low RPM's as well as real high RPM's. On a naturally aspirated car, cams are the main part that defines the powerband. Just as you tune the ignition timing by advancing or retarding the spark, you can tune the airflow with the cams. Going with more aggressive cams will slide the powerband over a little to the right, it'll want to pull harder on the high end but you'll lose some on the low end. Get too aggressive, and you'll lose so much from the low end that the car won't want to idle right. Formula 1 cars rev to 18,000 rpm but have to idle at 7,000 rpm, since they're optimized for top end. With a turbo car, the turbos throw another variable into it, because the turbos should be able to flow the air that the cams are tuned for. Race cams and stock turbos won't be a good match since the turbos will run out of flow well before the cams do. And stock cams and big turbos won't be a good match either. So to oversimplify it, you have 3 main variables- cams, heads, turbos. A Z engine with race cams and stock turbos will be a mismatch because the turbos will quit pumping air before the engine runs out of cam. A Z engine with stock cams and huge turbos will be a mismatch because the engine will run out of cam before the turbos are even fully spooled up. A Z engine with stock turbos and stock cams is good because the turbos peak along with the cams, they are evenly matched. A Z with midrange turbos like Sport 500's or 550's would be a good match with midrange cams. And a Z with big turbos like Sport 700's will work best with race cams and headwork, like Seb has.
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