GM's #241 5.7L LS1 head casting is one of the most commonly
available GM castings out there. While often swapped out in favor of 243's,
the venerable 241 is still capable of producing great power for the $ considering
how cheaply the castings can be obtained. Our 205cc CNC work is a good choice for guys who would like a bit more gain than our Performance Rebuild, but are not inclined to port the casting to its potential. This additional gain is attained via fully CNC porting the exhaust runners, and CNC machining the valve seat area of the intake port. The remainder of the intake port, and the combustion chamber are left as cast. Typical gains for our CNC work are in the
20-30rwhp SAE range over the as cast 241.
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 Exhaust Runners
- 100% CNC Professional Competition Quality Valvejob
- Factory Valves Cleaned & Precision Ground
- PCD milled to ensure flatness, surface finish, & achieve desired
chamber volume (60 - 72 cc)
- Intake Flange, Exhaust Flange, and Valve Cover Rail PCD
Milled to new surface finish specs
Machining & Labor Cost:
$795
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)