Quote:

Okay- I have a question for you guys-

How much naturally aspirated power will the stock pistons and rods live with in a 6.4 liter engine?

Forged crank,
powdered rods, cast pistons


Just a WAG, but I could see where the piston to valve clearance issues, plus the extra strength built into stock stuff for warranty would keep you safe with all the bolt on goodies you can screw together. Headers, ported heads, manifold, tune, cam, the works. I would guess somewhere around 150 more hp.
You can get a good idea by researching who is going fast with bolt on parts in the LX forums, and who is driving over some of their parts. The latter have found the limits
That is how I picked the boost for my Mustang GT blower package. Most guys who stayed below about 500 hp on a 300 hp 4.6 were not having trouble. Beyond that, it is a crap shoot for that particular motor. For normally aspirated, then total rpm becomes more important (pistons/rod speed)along with oil control so you don't starve the bearings.

Last edited by gregsdart; 11/26/14 04:42 AM.
8..603 156 mph best, 2905 lbs 549, indy 572-13, alky