On the camshaft I'd shoot for around 260-268 duration and .450 to .490 lift. Honestly, call Racer Brown and any other cam grinders and honestly tell them what you want. Get valve springs to match the cam you pick. You should have a nice 318, so I'd just rebuild what you have. Have the big ends of the rods redone .0002 undersize with ARP rod bolts. They should be the early light weight, bushed rods. Make sure the decks are equal on the block, bore and hone with torque plates with mains torqued to spec also. Add a windage tray, high pressure oil pump, and a true roller timing chain. I like Speed Pro ductile, file to fit, moly rings. Have your bottom end balanced. Mill the heads .020 and .019 on the intake side of the head, that should give you around 64 cc chambers. You can run stock valve sizes, or bump them up to 1.88 intake and 1.60 exhaust (360 sizes) not really necessary though. I would run stainless steel exhaust valves and the later Viton positive valve seals from Fel-Pro. Spring for a Competition valve job, and just clean up the bowls under the valves. Find true TDC and centerline your cam while the heads are off. On the exhaust, delete the heat valve on the passenger side manifold and consider "Jet Hot" coating the manifolds to keep the heat down in the engine bay. You will like the Accurate Commando exhaust. Your intake is great and either carb will work. I think the 9626s was designed for a 383, so it might be a tad rich. Play with both and pick the one you like best. When port matching, just do the top and sides. The Commando 904 has some nice parts from the factory. You could probably just reseal it, adjust the bands, change the fluid and filter, and be done for the next 100,000 miles. HP cars usually had 3.23 gears but we used to swap in 2.76 gears for highway cruising. We have run a 67 Barracuda like yours, except we kept the 273, for about 50 years and 300,000 miles. What a great car. Good Luck!
