Thread: 267 to 305 parts swap & Rebuild

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"The rear end gear ratio is less than 3 to 1."

Let's say it is 3.00:1 with a 26" tire. Using the second cam scenario that floats the valves at 5,600 with the recommended components, the math is as follows:
26" times 3.14159 equals 81.68" tire circumference. 5,600 divided by 3.00 equals 1,866 rpm's at the tire.

5,600 divided by 3.00 times 81.68 divided by 1056 (constant used in the formula) equals terminal speed of 144.38 MPH. If you factor in some slippage for the torque converter (5%), then you would multiply 144.38 by 0.95 and find a terminal speed of 137.16 MPH.

Trust me, you won't get that speed out of a mild motor because it won't make the horsepower required to pull the car that fast, but there's the theory of using that cam.

"what really happens at this point when you are above the cam's range?"
It floats the valves and stops making any more power. If the piston to valve clearance is well thought out ahead of time when building the motor, no damage will occur. The springs will be a little weaker after they are taken to this extreme, so the next time you do it the motor will float the valves at a lower rpm.

"And what type of stall converter do i use?"
With either of the cams I posted, a stock converter will work.