That cam choice is going to give up a lot of low end torque and therefore the car will have poor acceleration with 2.76 or 3.23 gears. With an A833OD you can use 3.91 gears and have an overall high gear ratio of 2.85:1. Good for tire shredding and cruising. The problem is the A833OD ratio spread is very wide and the RPM drop between gears is severe. With a much milder cam than the one you propose I was much, much happier with a standard 1:1 high gear A833.
How will you be raising the compression ratio to about 11:1 to compliment the chosen cam?
I'm going to quote a post of my own I made a little over a year ago in this thread: http://slantsix.org/forum/viewtopic.php?p=219667
Quote: Even in this community a lot of people seek parts for parts sake and not to reach a HP or ET goal. I think David Vizard put it best when he wrote something like: "You don't want to own a drill bit. You want the hole." In the same manner you don't want a 4bbl carburetor and intake manifold, you want the increased performance. Where a lot of people go wrong is buying parts they don't need, that don't help or help very little for the money spent (poor value).
The first performance slant I built was a performance failure. I had a Holley 390, Clifford intake, Clifford headers, Mopar 276°/.490" cam, forged +.030" pistons, high volume oil pump, roller timing set and electronic ignition. I thought I needed all that stuff, but didn't realize all that I had done wrong. The compression ratio was much too low, the distributor curve was wrong and it ended up eating the oil pump and cam gears. It had a really healthy sounding idle, but my '66 Dart was really slow.
After the cam and oil pump gear in that engine failed I put in a Comp 264° cam and a stock oil pump. The engine idled much better, was easier on the clutch and was just as fast if not faster. Recurving the distributor made it faster yet. When I finally got the compression ratio up and put big valves in the head the car really ran well. At this point I was road racing the car and poor oil control killed a rod bearing which took out the rod, a piston, the block and crank.
My '67 Valiant has a stock short block including the stock cam. I came into an Offy intake and a Holley 390 at a good price. I had a head milled for compression (it's all of 8.5:1), had larger valves fitted and ported the head myself. I had 2 1/4" exhaust with a Walker Dynomax Super Turbo muffler installed from the stock manifold to the bumper. Ignition is via a recurved stock electronic distributor and an HEI module and coil. This car is just as quick as my '66 Dart was and cost me a fraction to build. I may not have a real fancy drill bit this time, but I have just as nice a hole.
Since the engine is a number of systems working together you need to make sure they all play well together. Personally I would use a much milder cam, match it with the proper compression ratio and use a ported head with bigger valves.
Oh, yeah, with 3.21 gears and a 3-speed manual my Valiant gets 20 MPG on the highway. I could probably get is to about 22 MPH if the bottom end were fresh and I tuned the carb and ignition a bit more.
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Its up there under the "Slant 6 Forum" banner, but you can click on the picture in this post too.