275cc LS3 HEADS SPRING KITS:PAC 1209 DUAL SPRING KIT 7 Int 165 247 305

7 Int 165 247 305 350 385 402 Exh 115 170 210 235 248 255

20                    Exhaust:             1

8 Int 159 250 302 347 386 410 416 Exh 105 181 187 223 240 248 252

7 Int 145 220 270 315 355 375 Exh 110 152 200 220 230 235

Heavy cleaning

275cc LS3 HEADS SPRING KITS:PAC 1209 DUAL SPRING KIT 7 Int 165 247 305Our 275CC heads start as an aftermarket casting that we designed our own port for. These heads perform very well compared to other 260cc heads on the market. Our 260 LS3 ported heads include: Our in house CNC port Bronze valve guides PCD surfaced to your desired chamber size Proprietary competition valve job Your choice of spring kit Rev 2. 165 intake valves REV 1. 600 exhaust valves This is our most common setup, but if this doesnt meet your needs