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
2.200"/1.610" 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
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 LS7 cylinder heads is available with standard stainless valves, hollow-stem intake, and titanium intake valves. If you are going to run the stainless steel intake valves, we recommend limiting total valve lift to no more than .616" due to the weight of the intake valve. Upgrading to the hollow-stem intake valve will shed significant intake valve weight and allow for additional lift. The titanium intake valves will be the lightest choice of the three choices and offer the best lift possible!
Flow Data: @ 4.125" Bore Plate Superflow 600
LS7 Intake
LS7 Exhaust
PRC 265cc LS7 Intake
PRC LS7 Exhaust
.200
161
114
169
119
.300
227
171
248
179
.400
291
193
308
211
.500
330
203
351
224
.600
351
209
383
235
.650
353
204
388
241
.700
353
209
393
246
**Valve spring lift ratings are based on using titanium intake valves.
PRC 227cc CNC Ported Small Bore 3.9"-4" Cylinder Heads
Regular price
$2,912.99
Save $-2,912.99
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!!
Flow Data:
4.00" Flow Plate - No Exhaust Pipe
LIFT
INTAKE FLOW
EXHAUST FLOW
.100"
68 CFM
56 CFM
.200"
145 CFM
115 CFM
.300"
214 CFM
167 CFM
.400"
261 CFM
202 CFM
.500"
300 CFM
219 CFM
.600"
322 CFM
238 CFM
.650"
330 CFM
236 CFM
Jon M.
Casey is awesome, he called me several times. He truly wants to help you with your build. He’s not going to sell you something you don’t need. If you need help just call him very knowledgeable.
Mangum Racing 273cc LS7 Cylinder Heads
Regular price
$3,299.99
Save $-3,299.99
Mangum Racing 273cc Qualcast LS7 Cylinder Heads
Mangum Racing CNC Ported 273 LS7 Cylinder Heads
Built from the Qualcast stock style replacement LS7 casting, the Mangum Racing 273 program is designed for high-rpm, large-displacement LS combinations that demand elite airflow and structural integrity.
Featuring a 12° valve angle and OEM LS7 valve spacing/valve length, this 6-bolt casting delivers exceptional port efficiency while maintaining compatibility with LS7-based platforms. With a 273cc CNC intake runner and optimized 93cc exhaust port, this cylinder head is engineered for serious naturally aspirated builds and high-output boosted applications where the customer wants a near bolt on cylinder head.
Each set is fully CNC machined in-house on our Centroid 5-axis machining centers and finished on Newen seat and guide equipment. Every head is hand blended, assembled, and inspected in small batches to ensure dimensional accuracy and repeatable performance.
Airflow Performance
Tested on a SuperFlow 1020 with a 4.125” bore plate
Intake (Radius Entry)
.200” – 160 CFM
.300” – 255 CFM
.400” – 311 CFM
.500” – 352 CFM
.600” – 380 CFM
.700” – 390 CFM
Exhaust (No Pipe)
.200” – 117 CFM
.300” – 160 CFM
.400” – 209 CFM
.500” – 221 CFM
.600” – 230 CFM
.700” – 244 CFM
The 273 LS7 delivers outstanding mid-lift efficiency with dominant high-lift airflow, making it ideal for aggressive street / strip combinations.
Premium Hardware & Construction
6-bolt Qualcast LS7 casting
12° valve angle with OEM LS7 valve spacing
Stock Valve Lengths
273cc CNC intake port
93cc exhaust port
70.5cc CNC combustion chambers (milling available at no charge)
2.200” titanium intake valves
1.610” stainless exhaust valves
Bronze CHE guides
PAC .660” dual spring package
Titanium retainers
Viton seals
1.250” steel spring seats
Chamber softening available
Flat milling at .006” per cc
Minimum bore: 4.100”
Designed for LS7 Street & Strip Builds
With airflow over 390 CFM at .700” lift, the Mangum Racing 273 LS7 is capable of supporting serious naturally aspirated horsepower in 427+ cubic inch combinations.
Stock pushrod length works in many applications but should always be verified based on camshaft selection and final milling.
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.
PRC LS7x 265cc 7.0L CNC Head Porting
Regular price
$959.99
Save $-959.99
These are for customer supplied cylinder heads. We are not supplying castings! This is porting, valve job, and milling only!
2.200"/1.610" Valves (base price for exchange includes new stainless exhaust valves)
Available with PRC Double Spring Kit Complete With PRC Double Springs, Titanium Retainers, Seats, & Seals
Completely Assembled & Setup To Your Specs!!
Available With Stainless, Hollow Stems, or titanium valves!
Extensive CNC & dyno testing has resulted in one of the most affordable & powerful LS7 based cylinder heads available! Flowing up to 35cfm more than the stock GM LS7 head, the all new PRC cylinder head offers both unmatched power & airflow. The PRC LS7 cylinder head is available with standard stainless exhaust valves and titanium intake valves.
Flow Data: @ 4.125" Bore Plate Superflow 600
LS7 Intake
LS7 Exhaust
PRC 265cc LS7 Intake
PRC LS7 Exhaust
.200
161
114
169
119
.300
227
171
248
179
.400
291
193
308
211
.500
330
203
351
224
.600
351
209
383
235
.650
353
204
388
241
.700
353
209
393
246
**If stock valve guides are damaged or badly worn, there is an additional $150 fee to replace them. **If stock guides are replaced, stock springs can not be used due to the larger O.D. of the aftermarket guide. Spring kit must be replaced with aftermarket as well.
