This too. I've got a 2002 5.3, so it has the dished pistons, and 706 heads.

The 07+ has the flat top pistons and 243/799 heads.

I had to mill my 243 heads .030 and run a .040 thickness head gasket to achieve the same CR that the 07+ has from the factory.

 

I was hoping the OP would go for the 2007+ 5.3L engine for those reasons and he would already get the NNBS intake on the engine which is pretty much the exact same thing as the TBSS intake. He would reach his goal of 400 Flywheel HP really easy with the Gen IV 5.3l.

 

Well from what Im reading I want to look for a 07+ 5.3. My dad has an 07 new model 5.3 and its night and day difference when i drive his truck compared to my 2003 4.8. Im assuming its going to be harder to find a 07+ then an older one. Hmmm maybe i wanna change to the 5.3 in my truck now....

 

If I were to want a new engine in my truck, is it worth going for 5.3 from the 4.8. I know 6.0 is the ultimate but Im in Canada and they all seem to be for big $$

 

It would be an upgrade to a 5.3L, the 07+ 5.3L would be the one I would try and get though.

6.0 would be great if you could afford it obviously.

Sometimes you can find the LS1 5.7L car engines for a good deal, but don't pay more or the same as a 6.0 for one.

Or you can boost your current 4.8L with a turbo kit at 5-7 psi starting off, but that can all add up kinda quick especially if you want to do it the right way and upgrade the trans right away. The stock block is more than capable of holding that many pounds of boost, although I would recommend a ls6 cam and ls6 springs with new pushrods at minimal. This would be the most expensive overall..

 

There's a giant scrap yard in Quebec it's called Lecavalier auto parts found them on eBay they got everything shipping was cheap also

 

[QUOTE=
Or you can boost your current 4.8L with a turbo kit at 5-7 psi starting off, but that can all add up kinda quick especially if you want to do it the right way and upgrade the trans right away. The stock block is more than capable of holding that many pounds of boost, although I would recommend a ls6 cam and ls6 springs with new pushrods at minimal. This would be the most expensive overall..[/QUOTE]

Boost.....that sounds like fun....Ive been reading threads recently on here about how well the 4.8's are responding to turbos

 

Thanks I will definitly check it out...I love finding out about places like this