PRC 227cc CNC Ported Small Bore 3.9"-4" Cylinder Heads
Regular price
$2,399.99
Save $-2,399.99
Precision Race Components all new cylinder head castings completed with 227cc runners. For stock cubic inch LS1/LS2 applications requiring smaller chambers for extra compression
Small Bore Chambers For Increased Horsepower & Torque+ SPECIFICALLY DESIGNED FOR 3.9"-4" BORE APPLICATIONS
TSP Spring Kit w/ PAC Valve Springs Rated To .660" Lift
62cc CNC Machined Chambers(call for smaller CC)
CHE Bronze Guides
2.065" Intake / 1.600" Stainless Valves ***NOW AVAILABLE WITH HOLLOW STEM INTAKE VALVES!!!***
Factory Rocker Friendly!!*
The all new 227cc cylinder head is finally available for customers looking for the pinnacle of LS cathedral port performance. Now is your chance to own the same cylinder head that currently holds the fastest stock bottom end heads / cam record! The new 227cc port has been flow bench tested to flow over 320cfm & 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 with a smaller chamber designed for max power in stock cube applications.
This cylinder head was used on the Texas Speed 98 Camaro when it lowered the heads cam stock bottom end 1/4 mile record to 9.66!!
PRC CNC Porting Service - Cathedral Port Heads (Customer Supplied Castings)
Regular price
$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)
GM LSX Center-bolt Valve Cover Gasket
Regular price
$16.95
Save $-16.95
GM LSX center-bolt valve cover gaskets. Works in 1999+ GM valve covers!
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.
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.
Jaime V.
PRC As-Cast 225cc LS1/LS2 Cathedral Heads
Regular price
$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!
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
PRC 247cc CNC Ported Cylinder Heads
Regular price
$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.
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.
