Welcome Guest
Shopping Cart
Your cart is empty
Catalog Sections
POpen Grind, Tool Steel Billet, Clone 13HP
POpen Grind, Tool Steel Billet, Clone 13HP
Click to enlarge

POpen Grind, Tool Steel Billet, Clone 13HP

Item Number POPEN-GX390-TSB
Qty Break Price
1 $200.00
2 $190.74
3 $181.48
4 $172.22
5 and up $162.96


  • The P-Open is our #1 camshaft that is intended for a full tilt modified or open class. This cam offers larger duration with a lower lift. If your looking for a great cam, look no further.
  • Upgraded valve springs, billet rod, and billet flywheel are mandatory. A caburetor with a 1.50" / 38mm venturi is recommended.
  • Tool Steel Billet cores are the best choice in high RPM applications.
  • The two piece design of the Tool Steel Billet core allows you to advance or retard the cam to meet your application needs.


Engine: 390cc OHV Clone 13HP
Recommended Class:Modified / Open
Target (MAX) RPM:8000-8200
Spring Pressure (In / Ex): 65 lbs Dual Spring
Valve Lash (In/Ex):.003"
Ignition Timining:Pump Gas Not Recommended
110 Octane 34 Deg BTDC
Methanol 38 Deg BTDC
Compression Ratio:12.5-13.0 to 1 or Higher


Open: 71.0 BTDC89.0 BBDC
Close: 87.8 ABDC50.0 ATDC
Lift: .363".367"
C/L: 106.0 ATDC110.3 BTDC
DUR @ 50:263.3 Deg269.0 Deg