Pulling engine again because of machine shop mistake on forgetting to tighten cam gears.all of the valves have hit pistons .has anyone heard if these engines can handle it on bottom end?
Most say the crank is good to almost 1000 RWHP. The stock Manley rods are actually the weak point and some say they are good up to approximately 750RWHP if you replace the stock rod bolts with some better quality ARP fasteners.
The crank has been over 1200hp, the rods over 800hp, the pistons over 800hp. The weak link is people trying to make this kind of power with mail tunes and poor fuel upgrades and or detonation. The stock block is tough and has good internals to handle 700+ providing the tune and fuel quality is there.
You say your machine shop forgot to tighten cam gears, double check that we had a few MMR engines loose the cam bolts from issues with the end of the cam where the cam gear bolts to.
800HP on the stock pistons? It may make a few dyno runs at that level, but in real world driving/racing they won't last, especially when you consider the stock PTW clearence Ford used when assembling this car. These pistons expand at a rate faster than the iron block. Many, many, many 03/04 cars have literally ATE their pistons up at much lower HP levels than 800 due to heat. Even with the best tune in the world they won't last long at that level. That's why every 03/04 owner worth his salt will tell you to never perform high speed extended runs on this car with the stock setup.
800HP on the stock pistons? I bet they don't last very long at that level, especially when running the stock PTW clearence Ford built these things with. These pistons, once hot, expand at a rate faster than the iron block. Many, many, many 03/04 cars have literally ATE their pistons up at much lower HP levels than 800 due to heat. Even with the best tune in the world they won't last long at that level.
The bulk of the piston failure is detonation IE tune or a mechanical failure, fuel pump, etc. We have many customers cars running around making 650+ as daily drivers. Anyone looking to make 750+ needs to look into a built engine, ported heads and cams. The post asked about what can it take, not that I recommend it on stock internals. Anything over 700hp on the street imo is a waste.