[Joshinator99]

Originally Posted by cmitchell17

So I don't know this and this is an assumption but I would be willing to bet the internal engine components are built on a safety factor past 2 and probably around 3. Of course though I bet they have more difficulty meeting fatigue strength rather than ultimate strength requirements as I would think they would design for infinite cycle life. So basically they have to make sure the part is strong enough to resist a smaller amount of stress than peak expected stress over millions or basically an infinite amount of cycles. When they make it strong enough to have low enough stress at the non peak fatigue load conditions (think just the loading from the weight of the rotating assembly while running at highway RPMs not even considering combustion or any other loading) I bet it makes it even stronger to resist the ultimate loading we would be putting on it pushing big power.

Of course GM or any OEM would say any mods will be bad and destroy it and reduce engine life the thing is they design these things for extreme conditions, like running WOT for months on end simulating towing up a step grade at full power and stuff like that. In addition what if there is a design or material defect in one of the rods or pistons or too sharp of a radius that gets carried through millions of parts, it's cheap insurance to over design it instead of having to do millions of warranty claims.

When people modify these things although they might think they are doing everything perfect, they are introducing all kinds of variables (clearances, improper assembly, non-oem parts, etc) and deviating from a tightly controlled OEM environment and as like people said basically tuning it blindly while thinking a wideband O2 feedback Will give them all the information they need.

Like someone else said as well the GEN V platform was designed stronger than the GEN IV as GM increased the power output so they had to correspondingly increase the safety factor and probably meet the same durability requirements as before.

That is complete guess work, as I’m sure you’ll agree. I would bet a substantial amount of money that a penny pinching outfit like GM would never engineer a safety factor of 3 into those pistons and rods. You’re welcome to shoot for 1365 HP (455 x 3) on your build with OEM LT1 pistons but I’m going to take a hard pass. You might get one pull out of it…