[mikep]

Thats not really much of a cam. I run a similar grind with approx .500" lift at 234 duration on both sides with 108 degree centers and I have a smooth idle ( thats a relative term ) at 800-900 no problem with 10.2:1 compression. I dont dare go over 36 degrees total timing on 92 octane gas or I run into detonation. Thats with .125 domed pistons and 72 cc chamber 200 cc port world product sportsman II heads .Just from my experience having built a lot of truck motors over the years if you are never going or rarely going to haul anything and all your'e looking for is to have a hot rod truck then by all means ignore the conventional wisdom that says you need a short duration cam for low end torque. Low end torque is good for hauling around a 4000 lb camper or 2 cords of wood but too much low end will boil your tires off in short order and you will lose the race in a cloud of tire smoke if all you do is drive around with an empty bed all the time and race stoplight to stoplight. A 3000 or so stall converter and under 240 degrees @ .050" cam with 10:1 compression and good heads will give you more low end torque than you know what to do with and will come on like gangbusters on the top end. These trucks dont weigh any more than a chevelle and certainly less than a big chevy passenger car so cam away to your hearts content. Using too short of a duration cam will make you miserable if you like to get your foot into it like I do. Nothing worse than running out of steam at 5000 rpm.

None of the heads you have listed flow all that well to tell the truth and your better off selling them all off and buying yourself a set of
vortech heads from chevrolt . a set will run under $500 and the money you'll save on pistons will more than put you ahead of the game because you'll need flat tops only to give you your compression as the vortechs have something like 58 cc chambers and they flow better than anything chevrolet has ever put on a car. Or if you are dead set on using those heads .125 domed piston will give approx the compression you are looking for although remember that there isnt much of a HP difference between 10:1 and 11:1 but there is a huge difference in the type of gas you can get by with.

I use sealed power .125 domed hypereutectic pistons and am using awesome scat 4340 H beam rods with a steel crank with .003 bearing cleaance, all fully balanced. The set of 8 pistons cost less than $200 and I am fully confident running it to 7500 rpm all day long although my cam probably starts dropping power at 6500 and so will yours .

Also remember that buying 92 octane all the time sucks and that if you go to 11:1 you'll have to spike it with avgas or octane booster to keep it from rattling apart. It adds up.

A few more words of advice. Build your bottom end to handle all the power your heads and cam will give it. If the top end is going to provide 400 horsepower then build the bottom end to handle 400 horsepower ie steel crank, strong rods , 4 bolt main, ARP bolts etc. BALANCE YOUR ROTATING ASSEMBLY !!!!! It costs about $150 . Its worth it. Cut corners somewhere else .