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A larger throttle body has the ability to flow more cfm than the stocker. But it won't unless there is an engine behind it that draws more cfm. A larger throttle body will benefit most in the top end of the power range where the engine is drawing more air. But you're looking at maybe 1-2hp on the very top (4000-5000rpm). The stock camshaft/heads are going to run out of steam long before the engine will draw enough air to make a larger throttle body worth itself.
Should you swap in a 410 or 422 camshaft and focus your head porting on high rpm velocity, you can shift your powerband up a little farther and then the extra air being drawn from the engine could very well be constricted by the stock throttle body. In this case, it would be a good idea to upgrade the intake. But the expense is going to be low end torque.
Should you swap in a 410 or 422 camshaft and focus your head porting on high rpm velocity, you can shift your powerband up a little farther and then the extra air being drawn from the engine could very well be constricted by the stock throttle body. In this case, it would be a good idea to upgrade the intake. But the expense is going to be low end torque.
