Performance Driven Design's Premier CNC Porting Option for your GM LS 821/823/863 Cylinder Heads. 
 
Our committment to delivering "Performance, Precision, and Unparalleled Perfection" is evident with our no holds barred approach to treating your cylinder heads as if they were our own! We approach each set of cylinder heads with the utmost emphasis on attention to detail. We take immense pride in our work, and our manufacturing processes are always improving to ensure you recieve the absolute best bang for your buck!
 
Here is what you can expect from the PDD Process:
 
Complete Teardown/Inspection/Evaluation of the Cores
PDD's Premier CNC Porting Programs
Intake Ports
Exhaust Ports
Chambers (Some Chambers DO NOT apply)
Intake, Exhaust, Valve Cover Rail Machining(Like New Surfaces!)
Pressure Tested for Zero Leakages
Performance Valve Job
Head Deck Finishing for Proper Sealing Surfaces
Washed & Hand Deburring on all edges
Final QC checks to ensure 100% Process Control & Capability