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Edelbrock's New RPM Xtreme™ LT4 Cylinder Heads Deliver
406 Horsepower Out-of-the-Box

Edelbrock's new RPM Xtreme™ cylinder heads for GM LT1/LT4 engines (#61939) offer the best combination of as-cast port design and custom CNC porting technology available. By blending the affordability of as-cast ports with custom CNC porting in the critical areas (combustion chambers, intake entry, exhaust exit and intake/exhaust bowls), Edelbrock engineers are able to improve air flow and overall performance. Additional features include LS1 valves and conical springs for improved airflow and high-rpm valve train stability. This proven combination yields a powerful cylinder head at a lower cost than typical fully CNC'd heads. Available complete (#61939) or machined casting minus valves and springs (#61929).

Dyno testing on a stock 330HP LT4 engine with the addition of Edelbrock RPM Xtreme Series heads #61939, Edelbrock RPM Air-Gap intake manifold #7109, Edelbrock LT1 roller cam #2108 and throttle body #3810 resulted in an impressive 406 horsepower @ 6000rpm and 390 ft./lbs. of torque @ 4500 rpm - that's 76-horsepower and 50 ft/lbs of torque increase over stock.

All Edelbrock intake manifolds and cylinder heads are cast and machined in Edelbrock's own California facilities for absolute consistency and quality control.

    Features Include
  • Direct replacement on 1996 LT4 and 1992-97 LT1 with LT4 intake manifold
  • 5/8" thick deck for extreme durability
  • Fully CNC machined 54cc combustion chambers
  • CNC profiled195cc intake ports flow 265 cfm @ .600" lift
  • CNC profiled 75cc exhaust ports flow 185 cfm @ .600" lift
  • Stainless steel 2.02" intake and 1.57" exhaust valves
  • #61939 Retail Price: $979.00 ea.

For more information visit, or call (800) 416-8628

About Edelbrock, LLC
Founded in 1938, Torrance-based Edelbrock, LLC is recognized as one of the nation's premier designers, manufacturers and distributor of performance replacement parts for the automotive aftermarket. Edelbrock produces their core products in the United States of America using state-of-the-art equipment in their world class manufacturing facilities. Edelbrock, LLC encompasses five locations in Southern California and one location in North Carolina totaling more than 500,000 square feet.
For more info, please visit:

Edelbrock, LLC. .:. 2700 California St. Torrance CA. 90503