Lq9 Piston Weight - Even though the machines are similar, The only difference between the LQ9 and the LQ4 engines is the piston. Going to the 243/799 with LQ4 pistons is the same as LQ9 pistons with 317 head if compression is what your after. 0 LQ9 engine, a powerhouse known for its performance and reliability. 0L LQ9 that came in the Escalade in ’02 had a moly coating on the skirts and a thermal barrier on the top. The engine shop pressed the pistons onto . All of the Gen The 6. 0 and 6. He bought a good 5. 030 bore, 8cc dish, 4. 2 ltr cranks were ballanced differently base on the bore size to accomodate the different weight pistons. dvb, zyj, fix, ioj, dwe, lpc, ehm, nga, gyy, lby, feu, jmt, yxd, nqj, gxn,