Ive got a late model 5.0 in my 66 coupe, at least had it in there until today. Anyways it's out, does anyone know hw much power the stock bottom end can handle?

 

you may have hyper or forged pistons depending on the year 5.0, but the general rule is 400-500 hp and then they go boom.

 

do you know the year?

 

uuuuuhhhhh if the pistons are forged then i would say 450 but that is about the max for the block

 

500-550 at the crank if the person building it knows what they are doing and rpm is kept below 6500-6800. Cap walk is what will kill it.

 

550 is really pushing it, especially on the later model lighter weight blocks

 

those shackles are 65-68 it looks like....ok so 450 is an ok amount to put through the block and bottom end consistently?

 

Yes, use a main stud, when the caps walk is when the block breaks, it breaks right at the main bolt holes and goes upward

 

this is awesome advice.Next Im pulling the fuel injection and wiring off of another 5.0 in the car for mine.Which stuff do I need?ECU, Injectpr rail,etc???

 

For production small blocks 1.5 hp per cubic inch is the safe max, around 1.75 for big blocks. That is with proper machining and assembly. You also have to remember that a main girdle can only do so much, you can't run 800 hp on a stock 302/351 block just because it's girdled and expect it to live in your car for 5 years. If your building an engine around 450-500 hp and you want to run it 50-100k miles I would look into making the investment in a quality aftermarket block. If this is a weekend street/strip car that won't see alot of miles or wear and tear and you want to run 450-500hp than a girdled stock block will work as long as the machining and assembly is done properly.