318

Here are some of my thoughts..

If the crank needs to be ground;have it offset ground.This will bring the stock pistons up .010-.015 in the hole.So instead of your stock piston being down .060-.080 it will be something like.045 to .065.More compression AND more stroke with one machining cost.

Buy a stock windage tray for a small block mopar.Less than $130 bucks and can easily add 10 h.p.Aids in keeping oil in the pan as well.

If it needs pistons definitly go with the KB.They are within grams of each other and ease balancing.

Have the stock rods checked for straightness.Recondition them by hand deburring and polishing.Throw a good set of bolts in them and thier good to go.

Chuck the old heads.Get a new set of heavy duty magnums.I think they are around $265 each on ebay.Small combustion chamber and an .028 head gasket will put you around 9.5:1 without offset grinding.However a magnums combustion chamber lends itself to higher comp on todays gas with less timing.10:1 is not out of line .Larger ports than a 302 casting and larger valves than a 360 head.Will lose some low end torque but not enough to offset the real gains in mid and top rpm range.These are hi velocity fast burn heads so mileage and low- mid range tq will be more and better than a large port 360 head,without the low compression that comes with a 360 head.Emmisions will be better as well.Magnum also has a 1.6:1 rocker ratio.They run into interference around .520 lift so limit your cam to about .480 to take the 1.6 rocker ratio into account.There are at least 3 springs available for this head.

Put a 5/16 adaptor stud(available from comp) in the head and you can use chevy rockers.Doesnt get much cheaper than that!The factory magnum rockers arent much either.Harland Sharp also makes a drop in roller rocker assembly.Pricey though.

The only drawback is you will need to drill the heads for an la intake OR buy a magnum intake.You will need special length pushrods.7.625 I think.And magnum head bolts.La valve covers will fit if you wish to reuse them.You will need 8mm magnum valves and valve train(unless the heads on ebay come complete).When you order the cam make sure it comes with oil thru the pushrod style amc lifters.Thats how the magnum oils the heads.Most aftermarket mopar cams come with this style lifter anyways so it's not an extra cost.

400 h.p is achievable with the above cam and NO porting.302 casting will need to be ported quite a bit to make the same power.And probably wont have as much power under the curve.