What are the differences between the LQ4 motor and the LQ9 motor?

 

pistons, and i believe some of them had a little better rods

 

Straight from Wiki:

LQ4
The Vortec 6000, or LQ4, is a V8 truck engine. It is a bored version of the Vortec 5300. Displacement is 6.0 L (364 in³) from 101.6 mm bore and 92 mm stroke. It is an iron/aluminum (note that 2000 model year engines had cast iron heads) design and produces 300-325 hp (224-242 kW) and 360-370 ft·lb (488-502 N·m). LQ4s are built in Romulus, Michigan and Silao, Mexico.

LQ9
The Vortec HO 6000 or VortecMAX, technically the LQ9, is a special high-output version of the Vortec 6000 V8 truck engine originally designed for Cadillac. This engine was introduced in other truck lines as VortecMAX for 2006. It features high-compression (10:1) flat-top pistons for an extra 10 hp and 10 ft·lb, bringing output to 345 hp (257 kW) and 380 ft·lb (515 N·m). LQ9s are built only in Romulus, Michigan.

 

Plus the LQ4 has 317 heads, the LQ9 comes with 035 castings. Red83 is correct about the flat tops and better rods in the LQ9.

 

the 317 are also found on the lq9's as well

 

whats the max bore on them and stroke? can you take them equally as far?