Advanced Induction Cylinder Head Development
Ai 212cc CNC'd TFS 21° LT1 Cylinder Head Package

Our 212cc CNC'd 21 Degree TFS heads are ideally suited for those looking for the high HP potential of our CNC'd TFS heads with the ability to generate high compression ratios on as little as 350cid.  With supporting modifications this head is capable of producing approximately 525-575 SAE corrected horsepower with a daily driveable HR or SR camshaft, and well in excess of 600hp with more aggressive valvetrain packages and appropriate supporting modifications.  Our standard PSI beehive & lightweight steel retainer easily controls aggressive HR and mild/moderate SR lobes.  The optional Manley Nextek dual spring setup should be used for high lift solid roller applications.

Machining & Labor:
  • 100% CNC Ported Intake & Exhaust runners
  • 100% CNC Unshrouded & Contoured Chambers
  • 100% CNC Professional Competition Quality Valvejob
  • Bronze guides honed to ideal clearances per application
  • Additional CNC'd Pushrod Clearance (required for 3/8" pushrods or 1.6+ rockers!)
  • PCD milled to ensure flatness, surface finish, & achieve desired chamber volume (54 - 63 cc)
  • Professionally assembled for your specific intended use, camshaft, & valve train setup
Components:
  • TFS 21° LTx Castings
  • PSI 1511 MaxLife Springs (.625" Max net lift)
  • Ai Lightweight Hardened Steel Retainers
  • Manley 13098 Precision Machined & Hardened Locks
  • Ai Custom Machined & Hardened Chrome Moly Locators
  • Lightweight 8mm Manley RaceMaster Stainless Valves - 2.055" Int & 1.600" Exh
  • OEM Quality Steel Jacketed Viton Seals


  • Optional @ Same Cost: BTR .660" Capable Dual Spring Kit w/ Titanium Retainers


Cost: $2495


Labor and Component Options:
Upgrade to Titanium retainers - Cost: +$170
Upgrade to Manley Nextek .700" shot peened & fully polished Dual Spring Kit:
    221435-16 Dual Springs
    23611-16 Titanium Retainers
    42135-16 Hardened Spring Locators
    13098-16 Precision Machined Locks
    Steel jacketed Viton seals for dual springs

    Cost: +$325 over the standard PSI spring setup (This is a premium setup that is ~$800 shipped from Summit)

Add an Ai Billet Core Custom grind camshaft for $395 when bought w/ head work!

 Recommended Usage: 355 cid - 396 cid short blocks with piston relief/dish volumes of 5 cc (Naturally Aspirated 11.0 - 12.5:1 compression) to 31cc (Forced Induction, 8.0 - 9.5:1 compression).