< Heads
HRD LS 6-bolt
Aussie manufactured Higgins LS-series cast alloy CNC ported heads
Formally known as CID, our Aussie manufactured HRD Higgins LS-series cast alloy CNC ported heads are available to suit LS7, L98/LS3 ports for street and race applications.
Our LS heads are available with all these standard features and options:
- 6 bolts per cylinder
- Raised runners with extra material on the intake face, allow the use of factory intake manifolds
- Multiple port configurations
- Chamber volumes from 55cc to 70cc
- Made in Melbourne Australia
- All heads are fully CNC ported and feature CNC valve seats
- CHE valve guides and seats
- .750” thick Deck
- Spring pads will accommodate up to 1.650” diameter
- Machined to suit 7/16 rocker stud bolts – shaft mounted rockers.
Can’t see what you’re looking for? No problem. We have more LS port designs, but cannot possibly list them all, so please don’t hesitate to call or contact us.
flow charts
Our LS 6-bolt ports are designed and developed by Darin Morgan at Reher-Morrison Racing Engines.
HRD LS3 CNC ported
3.0″ min cross secion | 2.160″ intake valve | 1.60″ exhaust valve
| LIFT | .200 | .300 | .400 | .500 | .600 | .700 | .800 | .900 |
|---|---|---|---|---|---|---|---|---|
| INLET cfm | 147 | 215 | 277 | 329 | 360 | 370 | 376 | 381 |
| EXHAUST cfm | 108 | 144 | 171 | 200 | 235 | 242 | 248 | 251 |
HRD LS7 small bore 4in (suit LS3 block) CNC ported
2.80″ min cross secion | 2.150″ intake valve | 1.60″ exhaust valve
| LIFT | .200 | .300 | .400 | .500 | .600 | .700 | .800 | .900 |
|---|---|---|---|---|---|---|---|---|
| INLET cfm | 151 | 228 | 286 | 337 | 343 | 353 | 367 | 370 |
| EXHAUST cfm | 95 | 135 | 170 | 208 | 227 | 237 | 244 | 244 |
HRD LS7 CNC ported
3.20″ min cross secion | 2.20″ intake valve | 1.60″ exhaust valve
| LIFT | .200 | .300 | .400 | .500 | .600 | .700 | .800 | .900 |
|---|---|---|---|---|---|---|---|---|
| INLET cfm | 160 | 230 | 293 | 341 | 372 | 376 | 389 | 390 |
| EXHAUST cfm | 100 | 142 | 170 | 220 | 232 | 240 | 252 | 252 |
HRD LS7 CNC ported
3.30″ min cross secion | 2.230″ intake valve | 1.580″ exhaust valve
| LIFT | .200 | .300 | .400 | .500 | .600 | .700 | .800 | .900 |
|---|---|---|---|---|---|---|---|---|
| INLET cfm | 138 | 215 | 281 | 339 | 375 | 392 | 401 | 419 |
| EXHAUST cfm | 107 | 149 | 204 | 226 | 235 | 241 | 245 | 248 |
Retro Street head
Perfect bolt-on upgrade for any street car!
- Our LS3 6-bolt hydraulic roller heads will accommodate all GM OEM parts.
- 253cc port for 6L / 6.2L engine
- 260cc port for turbocharged engines
- 280cc port for blown & nitrous engines
- Three different exhaust port for all combinations
Call us for more information.
