angcobra

NOS likes high compression, you only need the low compression for Forced induction.
The block should be okay for 150 shot.
I am making 600 hp on my stock block.

88BlueGT

Are you running any kind of support system w/ that ?

angcobra

I have a main girdle if that is what you are asking?

88BlueGT

Yea, thats what I was asking. Just anything for added strength.

angcobra

As I understand the 5.0, the weaklink of the stock motor is the rod bolts, next is rods, then the block itself in the region of the main bearings.
The block is limited by the amount of metal in the main bearing area. Since the main blocks are castings, there can be large variations of strength in the metal itself. Typically failures do not occur less than 600HP, which should say the weakest ones are at that point and some better castings can go much higher. I guess that makes it a crap shoot on the stock blocks as to how high you can go.
In the aftermarket blocks, they have better control on the casting strength and they have the chance to put more metal in the main bearing area.

I have forged crank, forged rods, and forged pistons so my limitation is the block.
I installed the girdle and then had the mains align honed.
I have seen stock blocks making 900 HP in turbo car (Walker Dyno tune), but I am not that brave, it would be my luck I would have one of the weak blocks. I was shooting for 600 HP from the start.
One other note, NOS and manual tranny would be more detrimental for block failures becasue of the sudden nature the power comes on.