5.3 Truck engine mods?

[70rs]

Can anyone here tell me the best mods to perform to a 2008 5.3l /auto trans combo ?
It is 315hp stock. And just to be clear, it is from a 1/2 ton truck.
I'd like to shoot for 375 to 400 hp and keep it NA.
Which intake? Cam? Other mods?
And does anyone know how much the stock 4sp auto trans will take for power before it pukes?

Thanks for any input, I am pretty new to the whole LS thing but am forging ahead.

[ElkyZO6]

It won't take much to wake a 5.3 up. I think Car Craft took a little older one put a set of good header's and a mild cam with a Edelbrock intake(I think) and a 750 dp carb on it and made 90 hp over stock. If you are not going to balance the engine don't go crazy on the cam a lot of guys like to run LS6 cam's in thier trucks for good balance between driveabilty and power. Everyone makes intake's for them you just need one for a LS1. I can get good deals on gm performance part so if I can help let me know.

The 4l60e will live behind the power you're going to make, BUT not for long it needs to be beefed up. Any good tran's shop should be able to fix you up. One more thing heat is the number one enemy for a tranny, so a good cooler with a fan will help make it last. Good luck and let us know what you decide.

[70rs]

Thanks for the input Elky. I finally landed on a combination today.
LS1/manual trans from a GTO. So now I will have a whole world of performance goodies available anytime. And I won't have to worry about the trans overheating when I hammer it.
I originaly wanted a manual trans and was only considering the auto with that 5.3 because it was a package deal. It has since been sold.
Thanks again for the good info.

[ElkyZO6]

No problem. Are you going to leave it stock or do what you were going to do to the 5.3 to the LS1?