compression with 274cam

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ALSO IT IS MOSTLY A STREET CAR BUT I DONT CARE BOUT GAS MILAGE WITH THIS CAR. ITS NOT MY DAILEY DRIVER. IF I CARED BOUT GAS, I WOULD DRIVE A HONDUH

If it's mostly a street car then it's much more important to be making power down in the 1000-3000 rpm range than 4500 rpm up where you seldom run the engine. As you select a cam with more duration you keep moving the power band up the rpm range. The XE284 cam is not going to be making power where you need it with a street car.

My recommendation had no consideration for fuel mileage.