Thread: not too happy!

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Not enough gear for the cam.

Not enough ignition timing for the cam.

Not enough converter for the cam.

Not enough head for the cam.

Not enough intake manifold. Any carbureted street motor built today will benefit from a high-rise, dual-plane intake such as an Edelbrock RPM or Weiand Stealth intake manifold. They advertise making power from 1500 to 6500 and are the best street manifold you can bolt onto a street motor in my opinion. They will make around 40 hp more than a low-rise intake and will make it where you can use it on the street.

Too much cam for the available static compression ratio. Compression does not begin in the cylinder until the intake valve closes with the piston coming up the bore on the compression stroke. If the motor is light on static compression ratio and you install a cam that delays the intake closing point of the intake valve, some of the charge can be blown back up the intake tract through the still-open intake valve. Choosing a camshaft that will perform correctly is quite a juggling act when building a motor and too much or too little cam for the available static compression ratio can make or kill the combination.

Beginning in 1972, Ford began using timing chain sets that retarded the camshaft timing by up to 8 degrees in order to bring the motors into compliance with ever-more-stringent emissions laws. You may have inadvertantly installed one of these retarded timing sets in the motor and you would not have caught it if you didn't degree the camshaft upon installation. Retarding the cam will add to the top end performance while decreasing the bottom end "snappiness" of the motor.

For the benefit of you newbies out there, yes there is ignition timing and there is camshaft timing. Do not confuse the two. Ignition timing has to do with where the spark plug fires in relation to the piston position in the bore. Camshaft timing has to do with opening and closing of the valves in relation to the piston position in the bore.