first off i have searched for this kind of question, so...

im rebuilding a 5.9 and im at the point of do i need to upgrade the pistons or can i get away with using the stock ones. the goal is to get around 500 hp reliably.

thanks!

 

Lower compression forged pistons. Anything else won't last. Stock compression is north of 9:1.... you don't want that for forced induction. (or, limit boost to 5-7 PSI.... and still use better pistons.)

 

Oh contrere. Flyin Ryan has several guys pushing 450+ on SBE with boost. Devin Lewis is making 10 pounds plus a 225 shot on a high mileage bottom end for the last 2 years. It just takes the right tuner to make it last. But generally, forged bottom end is proper....that's the route I am going. Ryan himself is currently putting a D1SC on his stock everything truck and setting up for 14 pounds at redline.

 

Also, MAJOR warning if you decide to do it the right way instead of the cheap way: Do not use any of the Hughes kits. There are a number of people having bearing failures around 500 miles in. Order a kit directly from SCAT with a forged crank. The Hughes kits use SCAT Cast cranks. The SCAT forged internally balanced kits are $2200 for either 365 or 408 inches.