Weak point of 2 valve 4.6 motor.. RPM?

OinkAodeOink said:

So would you say the mod motor's are less forgiving then say a 92-up 5.0?
The 5.0's have the hyper pistons, cheap rods and cast cranks, but seem to take a a decent amount of abuse, and usually the block is first to go.

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I would say yes….as a whole, the modular engine is less forgiving for the most part than the OHV. The 5.0L has the same cheap hypereutectic pistons, but their design is a lot beefier and carry a lot more meat around the upper ring landings, where the mod motors tend to go. The rods in a 5.0L are actually pretty good. Much better in comparison than the spindly toothpicks that the modular engines are equipped with. The problem with the mod motors, are that once the piston goes, it usually takes the rod with it. As far as the crank….both the SOHC and OHV engines use a cast nodular crank. The SOHC crank just happens to be a little beefier and recessed deeper into the block adding to its strength in comparison.

Each engine has its flaws. For the OHV’s, they have problem keeping head gaskets in check as well as the block cracking along the lifter galley when the power starts to climb. The stock rods and crank are good until about 450rwhp, but I wouldn’t rev the crap out of it. The stock 5.0L block usually pukes at around 500-550rwhp. Sometimes less if the mains are not reinforced.

The modular engine on the other hand has the weak rods and pistons to contend with, but don’t have any of the head sealing issues that the OHV engine does and although it’s said the block is good for around 550rwhp, but I think this is more of a combination of the block and stock crank, that limits it, not the block alone as I’ve never heard of an iron block breaking.

Hows that for the run down....