For Immediate Release

For Technical Product Information Contact:
Smitty Smith
Technical Sales Coordinator
(310) 991-7744

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Jason Snyder
VP, Marketing
(310) 781-2222 ext. 2915

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

TORRANCE, CA - 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


Founded in 1938, Torrance-based Edelbrock, LLC is recognized as one of the nation's premier designers, manufacturers and distributors of performance replacement parts for the automotive and motorcycle after markets. For more information please visit us at

Edelbrock, LLC opened its first green sand foundry in 1990 in order to fully control the quality of the castings. A brand new robotically-controlled permanent mold facility was opened in 2007. The Edelbrock Foundries are ISO 9001 registered, delivering modern production solutions for aluminum casting and Made in the USA quality.

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