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Old 08-26-2012, 11:23 AM
ap72 ap72 is offline
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Originally Posted by vinniekq2 View Post
ap72,please learn the rule of 5252.

In terms I understand though not technical,the peak hp being 2 or more k higher than peak tq rpm will usually indicate higher hp numbers than torque.when you reach 5252 rpm,that is usually the x over spot,or it should have happened by then.There is hp being left on the table somewhere???

a 5500 rpm 327 though perky is no where near what it should do. a 1500 rpm range is too narrow for idael acceleration.In a perfect world you shift at max hp and the transmission drops the rpm to max torque rpm.not many transmissions drop 1500 rpms between shifts.
I wont post a detailed explanation like Bogie,that guy does a much better job of explaining the details
Again, there is absolutely no good information in any of this, BUT it does come from a long line of misunderstood BS, so it is understandable how a person may come to believe it carries some merit.

hp and tq always cross at 5252, there is no significance of that number though other than how hp and torque are defined, switch to metric readings and 5252 carries no significance.

To a certain point running a larger cam will produce more hp and it will produce it at a higher RPM... which means that if you don't ever run in that RPM the "increase in power" will actually make your car slower as it results in a loss of power in a lower RPM. Which is why you need to compare power output at the same specified rpm to get a better comparison.

For a perfect shift on a race track you do NOT shift at peak hp down to peak tq, you shift to maximize your average hp, meaning you shift past peak hp and fall to a place right below peak hp (how far in each direction depends on your power curve).

A 5500 rpm 327 maybe exactly what is needed depending on the application. If you run 50hp less than a more aggressively built 327 but are never in the rpm range it makes the additional power the engine with less power can actually make your car run a little faster.
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