5.3 with 4.8 pistons

[thirdgenbum]

When building my 5.3 I had my 4.8 pistons bored and pressed on 143 LS1 rods, engine runs great in my 81 K5 with stock lapped 862 heads and fbody manifolds. Don't quote me but I believe the L33 flat topped pistons are the same p/n as the 4.8 flat topped pistons. Either way they will work, Good luck with you build.

i don't believe so. the l33 had floating piston pins, where most 4.8's had pressed fit pins.

[cjriojas]

i don't believe so. the l33 had floating piston pins, where most 4.8's had pressed fit pins.

Does this mean that there was a difference in the connecting rods? I havent done any of this type of research and im curious.

[jansen]

I've got a set of floaters in the for sale section.

[thirdgenbum]

Does this mean that there was a difference in the connecting rods? I havent done any of this type of research and im curious.

yes, and i believe all genIV motors got the floating rods/piston combos, and looking at the two side-by-side will show that the genIV rods are quite a bit beefier.

[AGearHead4Life]

When building my 5.3 I had my 4.8 pistons bored and pressed on 143 LS1 rods, engine runs great in my 81 K5 with stock lapped 862 heads and fbody manifolds. Don't quote me but I believe the L33 flat topped pistons are the same p/n as the 4.8 flat topped pistons. Either way they will work, Good luck with you build.

awesome. Sounds like a cool build.

[AGearHead4Life]

I've got a running high mileage 5.3 that I'm about to drop the bottom end out of to put 4.8 pistons in before I drop it into my C10. My heads are milled .045" and running a 220r cam. I'll be checking PTV for sure. Your .030" mill should be safe, but that all depends on your cam.