Mark there is a debate for (which I have seen proof of) that it is not necessarily the threads that are the issue with tightening to 70lbs, but the deck of the block can easily be distorted when studs are over-tightened.
That cam mentioned has been reground taking material off of the heal to give it additional lift however the duration suffers and the torque band suffers because it's range (band) is pushed out even further. While I realize you have already purchased this cam, my recommendation is to use a Stipe IB330 or IB340. His 340 has a very nice, --and
FLAT torque curve that with a little more compression and carburetion will make mid-80 horsepower at about 2200 RPM with a little over 170 ft. pounds of torque. The best part is this is about the same all the way down to about 1400 RPM and then it has a very gentle drop-off from there.
Where this is an advantage is, let's say you are cruising along at 55 mph (which is about 2200 RPM w/ the 3.27 gear) when you start up a steep incline or hill. With Bill's camshaft, the torque (pulling power) basically stays the same until the vehicle drops back to around 36-37mph!! In other words, you basically have the same pulling power while your speed can drop off 20mph, --and then the torque of the engine really does not fall off until you get under 800-900 RPMs, which is about 23-24mph. Remember, the engine is not lugging at the speeds but even if you wanted to ensure you were not causing damage, you could make a 3rd-to-2nd synchro-ed gear change at about 25mph that would allow the engine to operate at about 1625 RPMs (the same engine speed as 42 mph in 3rd gear!). Heck, that is the same speed many here like to cruise at!!
Now here's the deal, I have not been able to get that type of performance (i.e.: Torque) out of a reground camshaft. If someone can show me real world dyno numbers with a reground camshaft, then I will gladly try it, ...but this is the combination that I have found works well for my typical customer's driving style. I know some people feel like the best bang for your buck is a high-comp. head, I sometimes think that a $400 camshaft is a better value than a $325 head. Again, just an opinion and your mileage may vary!!
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