Year Differences

Complete breakdown of part differences across production years 2002-2009.

⭐

Best Year: 2006-2009 for most performance parts (large port heads, beehive springs, oil squirters, valve reliefs, single mass damper)

Note: 2003-2004 were transition years - parts may vary within same year

1. Valve Cover ⭐

Part
2002
2003
2004
2005
2006
2007
2008
2009
Plastic Valve Cover
Aluminum Valve Cover
⭐ Aluminum valve cover is preferred
Better heat dissipation, can be machined for clearance if needed (1-2" material removal possible)

2. Crankshaft ⭐

Part
2002
2003
2004
2005
2006
2007
2008
2009
12 Counterweight (Early M10x1.5)
12 Counterweight (Late M10x1.0)
8 Counterweight (M10x1.0)
⭐ 12 counterweight crankshaft is preferred
Better balanced, proven to 1000+ hp and 10,200 RPM. Early 2002 has M10x1.5 flywheel bolts (NO aftermarket fasteners available!). 2003-2006 has M10x1.0 bolts (standard). 8-counterweight (2007-2009) is lighter but less proven.

3. Connecting Rods ⭐

Part
2002
2003
2004
2005
2006
2007
2008
2009
No Oil Squirter (23mm pin)
Oil Squirter (23.5mm pin)
⭐ Oil squirter rods are preferred
Sprays oil at piston underside for cooling - critical for turbo/high RPM. Note: 2006 is transition year, check your engine!

4. Cylinder Head ⭐

Part
2002
2003
2004
2005
2006
2007
2008
2009
Small Ports, Small Valves (19207470)
Large Ports, Large Valves (89017826)
⭐ Large port heads are preferred
Flow 15-20% better, support 500+ hp. Small port heads choke at higher power.

5. Valve Springs ⭐

Part
2002
2003
2004
2005
2006
2007
2008
2009
Straight Spring (12596078)
Beehive Spring (12592506)
⭐ Beehive springs are preferred
Lower reciprocating mass, safer to 7000+ RPM. Straight springs float above 6500 RPM.

6. Harmonic Damper ⭐

Part
2002
2003
2004
2005
2006
2007
2008
2009
Dual Mass Damper
Single Mass Damper
⭐ Single mass damper is preferred
More reliable, handles 10,200 RPM. Dual mass can separate. 2003 was transition year.

7. Oil Pan ⭐

Part
2002
2003
2004
2005
2006
2007
2008
2009
With Windage Tray
No Windage Tray
⭐ Windage tray is preferred
Prevents oil frothing at high RPM, better oil control. 2003 was transition year.

8. PCM / ECU ⭐

Part
2002
2003
2004
2005
2006
2007
2008
2009
P10 ECU
P12 ECU
E67 ECU
⭐ E67 ECU is preferred
Easiest to tune with HP Tuners, best VVT control. P12 can't adjust VVT timing.

9. Pistons ⭐

Part
2002
2003
2004
2005
2006
2007
2008
2009
No Valve Reliefs (23mm pin)
Valve Reliefs (23.5mm pin)
⭐ Valve relief pistons are preferred
Allow aggressive cam timing without piston-to-valve interference. Essential for performance cams. Note: 2006 is transition year!

10. Exhaust Manifold ⭐

Part
2002
2003
2004
2005
2006
2007
2008
2009
Early 6-1 Design
Later 6-1 Design
6-2-1 Design
⭐ 6-2-1 manifolds have best scavenging
Better exhaust flow, but ALL stock manifolds crack eventually. Rear bolt breaks constantly. Plan for aftermarket headers.

11. Oil Pump/Pickup ⭐

Part
2002
2003
2004
2005
2006
2007
2008
2009
O-Ring Style Pickup
Gasket Style Pickup
⭐ Gasket style pickup is preferred
Better seal for custom oil pans. O-ring style can leak. 2003-2004 were transition years.

12. Exhaust Cam Sprocket

Part
2002
2003
2004
2005
2006
2007
2008
2009
Early Helical Spline (19179010)
Later Vane 6X (12580314)
Later Vane 4X (12589782)
Different VVT phaser designs. All work, preference depends on tuning strategy.

13. Crank Position Sensor

Part
2002
2003
2004
2005
2006
2007
2008
2009
2-Wire VR Sensor (12567712)
3-Wire Hall Sensor (12597254)
Different sensor types for crank position. Both work reliably.

14. Cam Position Sensor

Part
2002
2003
2004
2005
2006
2007
2008
2009
Early Cam Sensor (12584079)
Later Cam Sensor (12576519)
08+ Cam Sensor (12597253)
Sensor plug angle changed on later models. Can be used interchangeably with wiring modification.