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ProMaxx Performance Products CHR640NB ProMaxx Performance Cylinder without Valvetrain for 91-04 Jeep Wrangler YJ, TJ, TJ Unlimited, Cherokee XJ, Grand Cherokee ZJ & WJ with 4.0 L

Quadratec Part #: 51108-0002
ProMaxx Performance Products Part #: CHR640NB
Description
Restore horsepower, compression and fuel economy to that tired engine with one of our factory replacement heads. Matches original performance flow. Cast # 0331, 0630 & 7120.

CARB Notice

  • Legal in California, or other states adopting California emissions standards, only for racing vehicles that may never be used, registered or licensed for use, upon a highway. Can not be shipped to California residents.
Details

These are the only NEW Jeep® cylinder heads (NOT rebuilt), available in the aftermarket today. Built with all new parts, these cylinder heads have been engineered to withstand the demands of aggressive off-road driving and will resist potential cracking and warping. The Jeep 4.0L and 2.5L heads feature hardened valve seats and heavier than stock castings to increase strength and durability of original equipment. Bare cylinder heads are also available less valves and springs. Gasket sets, pushrods and rocker arms available separately.

Installation Notes
Installation Difficulty:
Skill Level 3 IconLevel 3Advanced

Reuse original valves and springs.

Installation Time: 6-8 hours
Parts Included

Cylinder Head

Warranty
90 Day Limited Warranty.
  • Engine Size: 4.0L I-6
  • Engine Fuel: Gasoline
  • Shipping Weight: 74lb
  • Shipping Dimensions: 30in x 6in x 6in (L x W x H)
  • Jeep Cherokee (XJ)

  • 2001 Jeep Cherokee (XJ)
  • 2000 Jeep Cherokee (XJ)
  • 1999 Jeep Cherokee (XJ)
  • 1998 Jeep Cherokee (XJ)
  • 1997 Jeep Cherokee (XJ)
  • 1996 Jeep Cherokee (XJ)
  • 1995 Jeep Cherokee (XJ)
  • 1994 Jeep Cherokee (XJ)
  • 1993 Jeep Cherokee (XJ)
  • 1992 Jeep Cherokee (XJ)
  • 1991 Jeep Cherokee (XJ)
  • Jeep Grand Cherokee (WJ)

  • 2004 Jeep Grand Cherokee (WJ)
  • 2003 Jeep Grand Cherokee (WJ)
  • 2002 Jeep Grand Cherokee (WJ)
  • 2001 Jeep Grand Cherokee (WJ)
  • 2000 Jeep Grand Cherokee (WJ)
  • 1999 Jeep Grand Cherokee (WJ)
  • Jeep Grand Cherokee (ZJ)

  • 1998 Jeep Grand Cherokee (ZJ)
  • 1997 Jeep Grand Cherokee (ZJ)
  • 1996 Jeep Grand Cherokee (ZJ)
  • 1995 Jeep Grand Cherokee (ZJ)
  • 1994 Jeep Grand Cherokee (ZJ)
  • 1993 Jeep Grand Cherokee (ZJ)
  • Jeep Wrangler (TJ)

  • 2004 Jeep Wrangler (TJ)
  • 2003 Jeep Wrangler (TJ)
  • 2002 Jeep Wrangler (TJ)
  • 2001 Jeep Wrangler (TJ)
  • 2000 Jeep Wrangler (TJ)
  • 1999 Jeep Wrangler (TJ)
  • 1998 Jeep Wrangler (TJ)
  • 1997 Jeep Wrangler (TJ)
  • Jeep Wrangler (YJ)

  • 1995 Jeep Wrangler (YJ)
  • 1994 Jeep Wrangler (YJ)
  • 1993 Jeep Wrangler (YJ)
  • 1992 Jeep Wrangler (YJ)
  • 1991 Jeep Wrangler (YJ)
  • Jeep Wrangler Unlimited (LJ)

  • 2004 Jeep Wrangler Unlimited (LJ)
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