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OEM GM 3919840 Big Block Chevy Rectangular Port Heads 396 427 Clean Pair June 68

$ 976.27

Availability: 93 in stock
  • Manufacturer Part Number: Chevrolet BBC Rectangle
  • Return shipping will be paid by: Buyer
  • Condition: This is a pair of original GM cylinder heads for a Big Block Chevy Engine. The casting number on each head is 3919840. These heads are the high performance version with rectangular intake ports and closed combustion chambers. These heads were used by GM on late 1967-1969 L78 396/375HP, L71 427/435HP, and 427/425HP(450HP) L72 engines which were used on Yenko and COPO cars. This head was also used as a direct replacement for casting numbers 3856208, 3873858, 3904391, and 3964291. What a rare find!These heads are complete with valves, springs, retainers, locks, guide plates, and rocker studs. These heads just came out of an estate where they had been in dry storage since the 80's. They have been cleaned and checked for cracks with none found. The valves sizes are 2.19 inch intake valves and 1.88 inch exhaust valves. The ports are still stock size with some smoothing/deburring of the casting as shown. The heads are a true matched pair with casting dates of F 17 8 and F 18 8 as shown.
  • Brand: 427 L71 L-71 L72 L-72 COPO YENKO 840 L78 L-78
  • Other Part Number: 1968 1970 1966 1965 1968 1969 1970 Yenko COPO
  • Part Brand: 3919840 Square port hi perf high performance LS6
  • years: 67 68 69 70 71 72 3964291 375HP 375 HP 425 425hp
  • Interchange Part Number: 427 Camaro Chevelle Nova Corvette Impala 396 454
  • Surface Finish: 3856208 3873858 3904391 3904392 3919842 65 66
  • Refund will be given as: Money Back
  • Restocking Fee: No
  • Returns Accepted: Returns Accepted
  • Item must be returned within: 30 Days

    Description

    This is a pair of original GM cylinder heads for a Big Block Chevy Engine. The casting number on each head is 3919840. These heads are the high performance version with rectangular intake ports and closed combustion chambers. These heads were used by GM on late 1967-1969 L78 396/375HP, L71 427/435HP, and 427/425HP(450HP) L72 engines which were used on Yenko and COPO cars. This head was also used as a direct replacement for casting numbers 3856208, 3873858, 3904391, and 3964291. What a rare find!
    These heads are complete with valves, springs, retainers, locks, guide plates, and rocker studs. These heads just came out of an estate where they had been in dry storage since the 80's. The heads were removed in good working condition when GM aluminum L88 heads were added to the engine. The heads have been cleaned, stripped of paint, and checked for cracks with none found. The valves sizes are 2.19 inch intake valves and 1.88 inch exhaust valves. The ports are still stock size with some smoothing/deburring of the casting as shown. All threads are in good condition with no thread inserts or helicoils. The heads are a true matched pair with casting dates of F 17 8 and F 18 8 as shown. These dates decode as June 17th and 18th, 1968.
    These heads are being sold as good cores for rebuilding. These original 3919840 heads have become very hard to find. Don't miss this nice date matched pair.
    This is your chance to own the awesome HI PERF Big Block Chevy heads for your special engine or collection at a great price. Don't Miss Out!
    Check out my other listings for more rare and hard to find parts.