SBC DRP CNC PORTED 23 DEGREE
COMPETITION PORTED 240C CYLINDER HEADS
| TECHNICAL SPECIFICATIONS : | |
| Intake Valve Diameter: | 2.080″ |
| Exhaust Valve Diameter: | 1.600″ |
| Intake Port Volume: | 240cc |
| Exhaust Port Volume: | 84cc |
| Chambers CNC Machined | Yes |
| Chamber Volume: | 63-69cc |
| Spark Plugs | Angled |
| Minimum Intake CSA | 2.570″ |
| Maximum Intake CSA | x.xxx” |
| Minimum Exhaust CSA | x.xxx” |
| Maximum Exhaust CSA | x.xxx” |
| Intake Seat Angle | 45 |
| Exhaust Seat Angle | 45 |
| Flow Test Bore Size | 4.155″ |
| Exhaust Flow figures with pipe | NO |
| Intake Gaskets To Use | Felpro 1207 |
| VALVE LIFT |
.100″ | .200″ |
.300″ |
.400″ |
.500″ |
.600″ |
.700″ |
.800″ |
.900″ |
1.000″ |
| Intake Flow @28″ H2O | 78.9 | 140.3 | 197.4 | 252 | 293.7 | 309.8 | 318.9 | 323.9 | 324.8 | 324.8 |
| Exhaust Flow @28″ H2O | 52.7 | 107 | 149.2 | 179.4 | 204.4 | 218.3 | 224.2 | 228.3 | 228.6 | 230.4 |
Flow figures are not inflated for sales purposes.
Calibration is performed on both Intake & Exhaust side of bench from 50 to 450 cfm using 11 sharp edge orifice plates.
Flow bench numbers should not be the primary concern when purchasing your next set of cylinder heads.
Porting for Power ! NOT Flow Bench Numbers – Click Here for more info
RECOMMENDED USE AND INFO:
Suitable for 400 + cubed engines
On E85 Fuel With A True Solid Roller Camshaft These Heads Have Produced 658 Ftlbs and 774HP @ 7000 Rpm
In our L434S402SR Engine Package These Heads Have Also produce 590+ Ftlbs & 697HP on 434 cubes at 7000 RPM on with a Street Roller Camshaft On Pulp 98 Fuel
Offset Rockers are not required to produce these power levels
Intake being used must be able to be used with Felpro 1207 intake gaskets – Victor JNR & Super Victor Intakes require welding
This 5 Axis CNC porting program can also be cut into the Dart 23 degree series of cylinder heads.
| Description | Pavtek Part # | Price |
| 5 AXIS CNC PORTING ONLY: | ||
| 5 Axis CNC Competition Porting – Chambers/ Intake/ Exhaust –
Does not include cleaning, crack testing, valve guides, milling etc. |
CNC434S401 | $ 1155 |
| Assembled Cylinder Heads – |
H434S401S | $ 4250 |
| Consists of : | Outright | |
| Valves – New Stainless Steel Intake & Exhaust – Ferrea | ||
| Springs – Dual HP ( ISKY ) | ||
| Retainers – New HP chrome moly retainers | ||
| Valve spring locaters | ||
| Valve Locks – Comp Cams Chrome Moly | ||
| Valve Stem seals – Crane teflon | ||
| 5 Axis CNC Competition Porting – Chambers/ Intake/ Exhaust | ||
| Multiangle Valve Seat Geometry | ||
| Backcut valves | ||
| Valve guides clearance checked & honed if required | ||
| Surface milled to your desired CC’s ( 63 to 69 CC’s ) | ||
| Springs measured & setup to suit cam to be used | ||
| Final washed and assembled | ||
| LUD 16-9-2025 |
*** PLEASE NOTE WITH THE USE OF 9005 HEAVIER SPRINGS PRESSURES A ROCKER STUD GIRDLE “MUST” BE USED OR ROCKER POSTS WILL BE DAMAGED – USE PAVTEK PT-RSG-SBC001 ROCKER STUD GIRDLE AND COMP CAMS CC-4508-16 7/16″ ROCKER STUD GIRDLE ADJUSTERS
OR YOUR COULD USE A SHAFT ROCKER SYSTEM WITH 1 PIECE STAND
