Advanced Induction Cylinder Head Development
100% CNC'd High Compression 218cc GM 5.3L LS1 Cylinder Head Package

GM's 5.3L LS1 head casting serves as the basis for this 3.900" bore specific offering.  With your 5.3's or our new GM 706 castings, lightweight Manley Race Master Stainless valves, and lots of available P2V this is a great option for 440-480rwhp 3.900" bore builds.  Our GM 5.3L CNC work will generate 11:1 compression on a stock 346cid LS1 while retaining the stock available P2V which allows the use of large duration cams without cutting piston reliefs!  Static compression ratios into the 12.X:1 range are possible.  Typical gains for this CNC work are in the 40-55rwhp SAE range over the as cast 241, and 346cid LS1's can manage 440-480rwhp SAE with bolt-ons and one of our daily drivable HR cam grinds.

Pricing is for work applied to a pair (2) of cylinder head castings and components YOU supply unless otherwise noted.  We are happy to build your heads with whichever spring kit, valve, etc. you would like.


Machining & Labor Operations:
  • 100% CNC Ported Intake, Exhaust, & Combustion Chambers
  • 100% CNC Professional Competition Quality Valvejob
  • Factory Valves Cleaned & Precision Ground
  • PCD milled to ensure flatness, surface finish, & achieve desired chamber volume (50 - 60 cc)
  • Intake Flange, Exhaust Flange, and Valve Cover Rail PCD Milled to new surface finish specs
Machining & Labor Cost: $995
Machining & Labor + Manley Race Master 2.00/1.55" Valves Cost: $1195
Machining & Labor + Manley RM Valves + NEW GM 5.3L Castings Cost: $1595


Labor and Component Options:

Bronze Guide Liners installed & honed to ideal clearances to refurbish worn out guides. - Cost: $125
Replace OEM guides with Full Bronze Guides & hone to ideal clearances - Cost: $250

PSI 1511 MaxLife Endurance Spring Kit w/ OEM Replacement Seals. - Cost: $250
Manley 23622 Titanium Retainers for OEM, PAC, PSI, etc. beehive springs - Cost: $195
Lunati Gold dual valve spring kit w/ lightweight steel retainers.  Lift capacity to .660" - Cost: $225

Manley 221436 Nextek .660" shot peened & fully polished Dual Spring Kit:
    221436-16 Dual Springs
    23623-16 Titanium Retainers
    42334-16 Hardened Spring Locators
    13098-16 Precision Machined Locks
    Steel jacketed Viton seals for dual springs

    Cost: $525 bought w/ head work (This is a premium setup that is ~$700 shipped from Summit)




Dyno, Flow Bench, and Track Results: