I'm thinking about putting a turbo in my 03 4.6 but I'm wondering if its ok to run about 9 pounds of boost with stock internals. I'm just worried about having hypereutectic pistons and rods but would nine pounds be ok?

 

yes.

Why turbo on stock internals though?

supercharger... cheaper, same power doet.

 

usually with a turbo 9lbs is pushing it. I think most people do 5-6lbs and quit there until they build it. Depending on the size of the turbo your going to be making a lot more torque than the block wants.

 

^agreed. Turbos are different animals than blowers. You can slap a blower on a stock internal'd car and run 12-13psi no problem due to hp usually being pretty close to tq. However, turbos will make monster tq and thats what you have to watch out for on stock internals. Either way, they can be done just be more conservative with the turbo setup if you go that route and either one make sure you have supporting fuel as well.

 

I've seen many builds run 8-10psi safely. Also, if you size your turbo larger, that is if youre planning on building the motor eventually, you'll drop some torque off and bring the torque down at lower boost levels. Thats just from what I've seen. Which turbo or kit were you looking at?

 

you will make more power with a tubo on the same boost as a blower. take my V6 as an example. a buddy had a Procharged/intercooled V6 with 11-12 PSI and made barely 270 rwhp. at 6 PSI my V6 made 276 with a slipping clutch.

go turbo. it's much better.

 

Turbo FTW.