PRC 237cc CNC Ported Cylinder Heads

$2,912.99 Save $-2,912.99
1 in stock
Precision Race Components all new cylinder head castings completed with 237cc runners. For 370 cubic inch and larger applications with 4.00"+ bore sizing.

Click Here to SEE why we build better heads!

MADE IN THE USA!!
CAST IN THE USA!!
MACHINED IN THE USA!!

Features: 
  • 237cc Fully CNC Ported Intake Runners
  • 84cc Fully CNC Ported Exhaust Runners
  • TSP Dual Spring Kit w/ PAC Springs Rated To .660" Lift
  • 68cc CNC Machined Chambers(call for different chamber size)
  • CHE Bronze Guides
  • 2.100" Intake / 1.600" Stainless Valves  
  • Factory Rocker Friendly!!
  • ***NOW AVAILABLE WITH HOLLOW STEM INTAKE VALVES!!! SAVES APPROXIMATELY 15 Grams!!!***
The all new 237cc cylinder head is finally available for customers looking for the pinnacle of LS cathedral port performance.   The new 237cc port has been flow bench tested to flow over 330cfm & can support everything from smaller camshaft street engines all the way to all our race engines. This cylinder head is a combination of a max effort high flowing port combined. 

Flow Data:

4.030" Flow Plate - No Exhaust Pipe

 

LIFT INTAKE FLOW  EXHAUST FLOW 
 .100"   66 CFM  57 CFM 
 .200"    147 CFM  117 CFM
 .300"    225 CFM  170 CFM
 .400"    284 CFM  206 CFM
 .500"    325 CFM  227 CFM
 .600"    334 CFM  235 CFM
 .650"    339 CFM  241 CFM
PRC 237cc CNC Ported Cylinder Heads - MailOrder Tuner

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PRC CNC Porting Service - Cathedral Port Heads (Customer Supplied Castings)

$899.99 Save $-899.99

The price listed is for you sending your cathedral port cylinder heads (4.8/5.3, LS1, LS6, LS2, LQ4/9) to us for porting. Our stage 1 porting service will include the re-use of the stock vales.  Stage 2.5 will include aftermarket 2.02/1.57 stainless steel valves. We also offer valve spring upgrades.

PRC CNC Porting/Machining Service Includes:

  • Disassembly
  • Deep Cleaning
  • CNC Porting
  • CNC Valve Job
  • CNC Engraving of PRC Logos
  • CNC Milling to Your Specs
  • Reassembly
  • Pressure Testing

 

Click Here to SEE why we build better heads! All Precision Race Components (PRC) cylinder heads come fully CNC-ported and machined using state-of-the-art technology. With all PRC cylinder heads, quality and performance are our two highest priorities! In addition to this, you will not find a better performing cylinder head porting service at this price.  Call one of our sales consultants today if you have any questions or if you would like to discuss your specific application.

 

 Stage 2.5  5.3L Flow Chart
Lift Intake Flow
 Exhaust Flow
 .200" 147 cfm
 111  cfm
 .300"  207 cfm
  145 cfm
 .400"  254 cfm
  185 cfm
 .500"  291 cfm
  204 cfm
 .600"  308 cfm
  223 cfm

 

 Stage 1.0 LS6 Flow Chart
Lift Intake Flow
 Exhaust Flow
 .200" 147 cfm
 114  cfm
 .300"  207 cfm
  148 cfm
 .400"  255 cfm
  187 cfm
 .500"  292 cfm
  202 cfm
 .600"  313 cfm
  220 cfm

 

 Stage 2.5 LS6 Flow Chart
Lift Intake Flow
 Exhaust Flow
 .200" 147 cfm
 114  cfm
 .300"  207 cfm
  152 cfm
 .400"  255 cfm
  191 cfm
 .500"  292 cfm
  207 cfm
 .600"  316 cfm
  226 cfm

 

 Stage 1.0 LQ9 Flow Chart
Lift Intake Flow
 Exhaust Flow
 .200" 147 cfm
 114  cfm
 .300"  207 cfm
  148 cfm
 .400"  255 cfm
  187 cfm
 .500"  292 cfm
  202 cfm
 .600"  313 cfm

 220 cfm

 

 Stage 2.5 LQ9 Flow Chart
Lift Intake Flow
 Exhaust Flow
 .200" 147 cfm
 114  cfm
 .300"  209 cfm
  152 cfm
 .400"  258 cfm
  191 cfm
 .500"  294 cfm
  207 cfm
 .600"  316 cfm
  226 cfm

   

*Typically a 1-2 week turn around time once heads arrive at our facility.

*Stage 1 porting NOT available for 4.8L and 5.3L castings due to the factory 1.94" intake valve size.  All 4.8L and 5.3L cylinder heads must select the stage 2.5 option that includes 2.02"/1.57" stainless steel valves!

 

Castings: 

  • 4.8/5.3 (706/862)
  • LS1 (241/853)
  • LQ4/LQ9 (317)
  • LS6/LS2 (243/799)
PRC CNC Porting Service - Cathedral Port Heads (Customer Supplied Castings) - MailOrder Tuner

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PRC LS7x 265cc CNC Small Bore Heads

$3,935.99 Save $-3,935.99
Requires at least a 4.065" Bore 

Precision Race Components LS7 CNC 265cc ported cylinder heads. 

Click Here to SEE why we build better heads! 

MADE IN THE USA!!
CAST IN THE USA!!
MACHINED IN THE USA!!
 
  • PRC 6-Bolt LS7 Cylinder Heads with Thicker Deck Surface
  • Will Work on Both Standard GM 4-Bolt & Aftermarket LSx / RHS 6-Bolt Style Engine Blocks
  • 2.205"/1.59" Valves
  • TSP .660" Dual Spring Kit w/ PAC Springs, Retainers, Seats, & Seals
    Springs, Titanium Retainers, Seats, & Seals
  • CHE Bronze Guides
  • Completely Assembled & Setup To Your Specs
  • Available With Stainless Steel, Hollow-Stem, or Titanium Intake Valves
  • 68cc Chamber Size as Standard
Extensive CNC and dyno testing has resulted in one of the most affordable and powerful LS7-based cylinder heads available! Flowing up to 35 CFM more than the stock GM LS7 head, the all-new PRC cylinder heads offer both unmatched power and airflow!

The PRC Small Bore LS7 cylinder heads are designed for both stroker, and stock cube applications with a 4.060"-4.100" bore.  For bores larger than 4.100" bore checkout the PRC LS7 265cc & 285cc cylinder heads!

The PRC LS7 cylinder heads are available with hollow-stem intake and titanium intake valves. We recommend no more than .625" total intake valve lift with the hollow-stem intake valves and no more than .670" total valve lift with the titanium intake valves.

 

 

Superflow 600
  

 

    PRC 265cc 
LS7 Intake		   PRC LS7 Exhaust
 .200  169  118
 .300  246  176
 .400  304  208
 .500 348  221
 .600 380  230
 .650 383  235
 .700 388  240

 

 **Valve spring lift ratings are based on using titanium intake valves.

 

PRC LS7x 265cc CNC Small Bore Heads , TFS LS7 Heads , BTR - Mail Order Tune

PRC LS3 Aftermarket 6-Bolt 260cc CNC Cylinder Heads

$2,937.59 Save $-2,937.59

All Precision Race Components (PRC) cylinder heads come fully CNC-ported and machined using state-of-the-art technology!

Click Here to SEE why we build better heads!


MADE IN THE USA!!

CAST IN THE USA!!

MACHINED IN THE USA!!


PRC's aftermarket casting LS3/L92/L99 cylinder heads come standard with the following options:

  • NEW PRC 13-Degree Valve Angle LS3 Castings
  • Improved Piston-to-Valve Clearance For Extra Compression & Larger Camshafts
  • Smaller Than Stock Intake Port Volume For Improved Port Velocity
  • Manley Stainless 2.185" Intake, 1.60" Exhaust Valves
  • Billet Rocker Pedestals
  • TSP .660" Dual Spring Kit w/ PAC Valve Springs, Titanium Retainers, Seats, & Seals
  • CHE Bronze Guides
  • Completely Assembled and Milled to Your Specifications
  • 60-68cc Chambers

All PRC cylinder heads are extensively researched and tested. The all-new PRC aftermarket casting LS3 cylinder heads are designed to flow considerably more than a gm ported casting while keeping the port sizes smaller for improved port velocity. The result is a cylinder head that is smaller than a stock GM LS3 port and moves more air than any other ls3 cylinder heads! 


The all new PRC aftermarket casting LS3 heads are the perfect option for customers looking for the ultimate in LS3/L99/L92 cylinder head technology


The PRC aftermarket casting LS3 cylinder heads are available in 2 different configurations: 


  • 255cc Runners for max effort stock cube LS2/LS3/L99/L92 engines looking for a 370cfm cylinder head that can be aggressively milled & still keep better than stock p/v
  • 260cc Runners For LS3/L99/L92 stroker engines needing a 380cfm+ cylinder head!

The 13-degree valve angle will allow for the ability to run more compression and larger camshafts thanks to additional piston-to-valve clearance!!  

 Lift

Intake Flow 

 Exhaust Flow

 .200"

 157 cfm

 117 cfm

 .300"

 224 cfm

 170 cfm

 .400"

 279 cfm

205 cfm

 .500"

 329 cfm

 225 cfm

 .600"

 360 cfm

 235 cfm
 .650"  372 cfm  240 cfm
 .700"  380 cfm  243 cfm


With all PRC cylinder heads, quality and performance are our two highest priorities! In addition to performance, you will not find a better performing set of cylinder heads at this price (cost is for the pair!). Call one of our sales consultants today if you have any questions or if you would like to discuss your specific application. 

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PRC As-Cast 225cc LS1/LS2 Cathedral Heads

$2,203.19 Save $-2,203.19
Precision Race Components all new as-cast cylinder heads completed with CNC machined chambers & valve guides. For  LS1/LS2 applications requiring a high flow aftermarket cylinder head at a unbelievable price!

Click Here to SEE why we build better heads!

MADE IN THE USA!!
CAST IN THE USA!!
MACHINED IN THE USA!!

    • As-Cast 225cc Intake Runners With CNC Machined Chambers & Valve Guides For Unmatched Flow!
    • Small Bore Configurations for extra compression applications while keeping good piston to valve clearance
    • Large Bore Configurations for customers looking for bigger bores such as stroker or boost applications
    • 62cc or 68cc CNC Machined Chambers (Can be milled to your desired specs)
    • 2.06" Intake / 1.600" Stainless Valves
    • Utilizes Factory LS1 Rocker Arms
    • Includes TSP Dual Spring Kit w/ PAC .660" Valve Springs!
    • ***NOW AVAILABLE WITH HOLLOW STEM INTAKE VALVES!!! SAVES APPROXIMATELY 15 Grams!!!***

The all new PRC 225cc As-Cast cylinder heads are finally available for customers looking for the ultimate as-cast cathedral LS heads available.  The new PRC as-cast intake port has been flow bench tested to flow over 320cfm & can support everything from smaller camshaft street engines all the way to all out race engines. This cylinder head is a combination of a max-effort, high-flowing port combined with a smaller chamber designed for max power in stock cube applications. You have your choice of the 62cc chambers used in the PRC 227cc cylinder heads or the 68cc chambers used in the PRC 237cc cylinder heads. We can mill additionally to get to your desired chamber size for no additional charge! 


Flow Data (4.00" Flow Plate - No Exhaust Pipe):

 

LIFT

INTAKE FLOW 

EXHAUST FLOW 

 .100"  

68 CFM 

56 CFM 

 .200"  

 145 CFM

 113 CFM

 .300"  

 210 CFM

 164 CFM

 .400"  

 257 CFM

 200 CFM

 .500"  

 300 CFM

 214 CFM

 .600"  

 318 CFM

 229 CFM

 .650"  

 321 CFM

 230 CFM
Texas Speed and Performance Precision Race Components Heads , LS1 heads , LS2 heads , Turbo 5.3
Texas Speed and Performance Precision Race Components Heads
Texas Speed and Performance Precision Race Components Heads , LS1 heads , LS2 heads , Turbo 5.3
Texas Speed and Performance Precision Race Components Heads

PRC 247cc CNC Ported Cylinder Heads

$2,774.39 Save $-2,774.39

Precision Race Components all new cylinder head castings completed with 247cc runners. For 408 cubic inch and larger applications with 4.03"+ bore sizing.

Click Here to SEE why we build better heads!

MADE IN THE USA!!
CAST IN THE USA!!
MACHINED IN THE USA!!

Features: 
  • 247cc Fully CNC Ported Intake Runners
  • 84cc Fully CNC Ported Exhaust Runners
  • TSP Dual Spring Kit w/ PAC Springs Rated To .660" Lift
  • 68cc CNC Machined Chambers
  • CHE Bronze Guides
  • 2.120" Intake / 1.600" Stainless Valves
  • Factory Rocker Friendly!!*
  • ***NOW AVAILABLE WITH HOLLOW STEM INTAKE VALVES!!! SAVES APPROXIMATELY 15 Grams!!!***
The all new 247cc cylinder head is finally available for customers looking for the pinnacle of LS cathedral port performance.   The new 247cc port has been flow bench tested to flow over 360cfm. 

Flow Data:

 No Exhaust Pipe

 

LIFT INTAKE FLOW  EXHAUST FLOW 
 .100"   66 CFM  57 CFM 
 .200"    147 CFM  117 CFM
 .300"    228 CFM  170 CFM
 .400"    282 CFM  206 CFM
 .500"    321 CFM  227 CFM
 .600"    343 CFM  235 CFM
 .650"    355 CFM  241 CFM
.700"     360 CFM    245 CFM  
PRC 247cc CNC Ported Cylinder Heads - MailOrder Tuner
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