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Building And Designing Engines Since "1978"

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We Are Not A Dealer Of Pro-Top Line Heads We Just Use The On Our Engines

The Worlds Most Powerful Cast Iron Cylinder Heads!


Manufactured By PRO TOPLINE


These are top quality high performance 23 cylinder heads that features phosphor bronze exhaust valve guides for superior heat dissipation and manganese bronze intake guides for longer life.


This head will take Std rocker covers or late model centre bolt covers and Std type screw in studs @ rockers. Unique multi angled inlet & radius exhaust valve seats will out flow the competition by 5%. Also features thick deck faces for angle milling.






We hand assemble these heads using Stainless Steel Valves , High Performance Springs, Retainers, Keeper, Screw In Studs, And Guide Plates. As we check each valve for proper spring pressure And installed height . To ensure no coil binding and valve floating when reaching high RPM.

On Our 350HP, 375HP, And 390HP Engines We Use A 176cc Intake Runner And 64cc Combustion Chamber.

While On Our 400HP+ Engines We Use 180cc Intake Runner And 64cc Combustion Chamber.

Flow Data Tested @28" Of Water















73/57 150/100 206/156 242/176 257/186 263/190 270/194