hi all
i am really new on the 5.3 truck world so i might sound stupid lol

i need to change the Pistons and the connecting rods on my freinds 5.3 silverado cuz he is going to have some really Big shots of NOS on it, about 150-250 shots of NOS

i have been looking around for some good pistons and connecting rods but i am little bit lost here. JE, Ross, Lunati, Manly !

i need your advice guys about the best pistons and connecting rods, Plus the correct sizes of them or there Part Numbers so i wont spend time and money on the wrong parts

Thanks for the help guys

 

The 5.3L rods are the exact same as the 5.7 and 6.0L ones, 6.098" in length. The rods themselves tend to be decent, rumor has them holding 500+ HP. The rod bolts on the other hand are the weak link. ARP makes the best stuff. Since you are going to change the pistons out go ahead and find some stock 5.7L rods ( easier to source out ) that include the ARP bolts.
I hear Ross makes some custom forged pistons for the 5.3/4.8 engines, 3.78" bore size, for around $700 or so. Or, if you really want to get nasty you can bore out the stock block to the 5.7L size, 3.898" thru 3.905" depending on piston choice, and pick up less expensive LS1 motor internals. The cost of the bore work would probably be covered by the reduced cost of the custom pistons.
God I love the "redundancy" of the GenIII motors! Lots of options...

 

Thanks for the help sir
but is it safe to bore the 5.3L engine to a 5.7L ?
is it a iron Block that my freinds truck has or an alluminum Block

P.S: it is a 2000 Silverado 5.3L

 

its an iron block

 

Yep, it is iron.
Yep, it is safe to bore that much ( check my signature out ).
I had the block sonic checked pre and post, thinnest post area was 0.157" with 0.150 being the "safe" zone. There is a possibility that manufacturing core shifts could cause a problem but I have heard the tolerances and quality on the GenIII motors is excellent. I have also seen bored and honed blocks only on eBay for decent prices ( except shipping, those blocks are heavy! ).

 

Boy, you're lucky KTM chimed in. He just saved you a ton of time. He knows these motors inside and out. LOL

*waits for Big Tex to chime in*