18 C™ Series/18°

 
 

 


The BRODIX 18 C cylinder head has an 18° valve angle that works well on dirt late model or serious drag racing applications.
This head has special valve centerlines and dowel location requiring special components. Interlocking valve seats are installed along with replaceable phosphorous bronze guides.
The combustion chambers may be angle milled down to the mid 40 cc range without weakening the deck surface. The 18 C has two exhaust bolt patterns available and a 5° intake face requiring a special intake manifold and components.

Package Heads

Facts and Related Components

• PS CB:
Valve Bowls Blended

• PS MI:
Match Intake Port to FP 1282

• PS Valve Job:
Competition Valve Job

• Intake Valves:
2.180 x 5.540 o.a.l. – BR 60518D

• Exhaust Valves:
1.625 x 5.540 o.a.l. – BR 60154

• Valve Springs:
1.550 Roller Valve Spring – GA 1000,
240 lb Closed, 550 lb Open,
1.950 Installed Height,
.700 Maximum Lift

• Retainers:
1.550 10° Titanium – MA 2398BR

• Valve Locks:
10° Jumbo – CC 611

• Rocker Studs:
Shaft System Required

• Valve Seals:
11/32 – US VS529V

• Torque Heads:
70 ft-lb

• Torque Rocker Studs:
40-45 ft-lb

• Intake Gaskets:
Modified FEL-PRO 1282

• Head Gaskets:
350 – FEL-PRO 1003, COMETIC C5399
400 – FEL-PRO 1004, COMETIC C5403

• Exhaust Gaskets:
Spread Port-
BRODIX MG 52464 (trim to fit),
COMETIC C5424

• Head Studs:
ARP 234-4727
(12 pt With 3/8 Center Studs)
ARP 234-4728
(12 pt For SP 18 SP C AP Heads)

• Accessory Bolt Holes Are Drilled

• Spark Plug Starting Points:
NGK R5671A-10 for Alcohol
NGK R5671A-9 for Racing Gas

• Spring Pockets:
1.550 out of the Box, May Be Cut to 1.625-No
Larger or Deeper

• Valve Angle:
18°

• Angle Milling:
.0065 in per cc

• Flat Milling:
.0055 in per cc

• Angle Machining:
Not Available

• Pushrod Slots:
58/107

• Stud Girdle:
Not Available

• Rocker Arms:
Shaft System With 58/107 Spacing,
Check Heads for Intake Offset
– T&D 2229, JESEL KPS 15409
(WP 18 SP C, BP 18 SP C AP), T&D 2238
.750 Offset (WP 18 SP C AP)

• Lifters:
.180 Offset

• Pistons:
Special 18°

• Pushrods:
Special Length

• Intake Face Angle:

• Valve Centerline:
58/107

• Intake Manifold:
HV 1813 / HV 1814 (WP 18 SP C, BP 18 SP C)
Custom (WP 18 SP C AP)

Flow Chart cfm @ 28″ H20

 
Valve Size

0.200

0.300

0.400

0.500

0.600
0.700
WP 18 SP C
HUT 921.4 A
(CNC Ported)
2.180
Intake
157 230 280 329 360 367
1.625
Exhaust
112 167 209 227 238 245
BP 18 SP C
(CNC Ported)
2.180
Intake
163 232 288 335 351 360
1.625
Exhaust
119 172 214 233 242 250
WP 18 SP C AP
(CNC Ported)
2.180
Intake
154 224 278 328 369 395
1.625
Exhaust
134 175 241 261 270 274
The WP 18 SP C are available in several intake port sizes. Ask a BRODIX representative which size would best fit your application.

Basic Easy Order Numbers

Part# Easy
Order #
Port
Vol.
Cham.
Vol.
Int/Ext
Valve
Spring Seat
Pressure
Spring
Diam.
Ret.
ST/TI
Per
18 SP C Bare
1180003 185 40         2
18 STD C Bare
1180005 185 40         2
WP 18 SP C Bare
1188001 Specify Port Program and
Chamber Volume Desired
      2
WP 18 SP C Pkg
1188102 Specify Port Program and
Chamber Volume Desired
240 1.550 TI 2
WP 18 SP C AP Bare
1188003 266 57         2
BP 18 SP C AP Pkg
1188105 266 57 2.180 / 1.625 240 1.550 TI 2
BP 18 SP C Bare
1188004 254 56         2
BP 18 SP C Pkg
1188106 254 56 2.180 / 1.625 240 1.550 TI 2
BP 18 SP C Combo
9991025 254 56 2.180 / 1.625 240 1.550 TI 1
BP 18 SP C Combo
With T&D Rockers
9991026 254 56 2.180 / 1.625 240 1.550 TI 1