The vendor have 243 799 molds. numbers just GM system when mold made. a head a problem helps track where problem started. only difference the heads production variance. Case closed. to Bob Mr. X. Mr. machined first 243 heads at GM Research.
706 vs. 317 Modified (NA) 5.3LRight the bat, is obvious the stock 5.3L 706 heads easily outperformed 6.0L 317s. was more impressive you the fact the .
I'm putting a fresh 6.0 LS for pickup, primarily pulling enclosed race car trailer.I three sets heads, 706 , 243, 317 heads be best for rpm TQ? can approx 10.5 11:1 either set heads, piston selection. see the 706s the smallest valves smallest intake ports CC.
These heads be CNC ported remove vane improve airflow. RPO LS7 cylinder heads 356-T6 aluminum 70cc CNC ported combustion chambers, raised square port, CNC ported intake ports 259cc runners, D-port, CNC ported exhaust 86cc runners, 2.205˝ intake valves 1.610˝ exhaust valves.
SLO 6.0 / 447 c.i. LSX Block Build 100mm MAF Intake, Nick Williams 102mm Throttle Body, Fast LSX 102 Intake Manifold, PRC Heads Kooks 1 7/8 in. 3 in. Stepped L/T's, 3" Road Connection Pipes, Cutout's, Magnaflow 3" Competition Catback Hurst Competition/Plus Shifter, RPM Level T-56 Transmission, SPEC Super Twin Metallic Discs GForce 4.0" Alumnium driveshaft billet pinion yoke .
Honestly, LS6 heads flow well you just put sold cam your car a spring upgrade take money do different it, vice buy set heads may flow little than 243s. However, have grat CAM, you looking a more ponies, with AFRs.
I disagree the LS3 heads. would agree they a better power increase a stock 241 head, a properly ported cathedral port head better. LS3 heads big intake valves which, a 4.00" bore application, put close the cc wall the cylinder bore hurt power.
Choosing best LS cylnder heads for vehicle be difficult. Cast iron heads generally durable less efficient, aluminum billet aluminum heads lighter more efficient. selecting head, must the engine type, power output want achieve, budget, the installation process. .
