1997 Ski-Doo Factory Shop Manual Volume Two, Page 80Get this manual
Sub-Section 03
Section 03 ENGINE (454, 494, 583 AND 670 ENGINE TYPES)
Torque screws no1 to 10 Nm (90 lbfin)RAVE SYSTEM Install exhaust valve in cylinder with its mention TOP upward (see illustration at removal)Install gasket and valve rod housing with their passages toward bottom
A24C07A
EXHAUST SIDE 1Larger holes
All Models
2, Cylinder Head Screw
ENGINE TYPE 454, 494, 583 and 670 CYLINDER HEAD SCREWS TIGHTENING TORQUE 29 Nm (21 lbfft) Apply grease under screw head