Is there much difference in the 241 and 243 heads?

 

Stock the 243's flow about 30cfm more on the intake at.600 in the low 260cfm range. I can't remember exhaust flow #'s.

The 243 is plainly a better head and a great bang for the buck....Especially if you find a Z06 set with the light valves....

 

243 head also has a smaller combustion chamber making for a higher Compression ratio.

 

I was looking at a late model pick-up today (4.8) and it had 243's on it, it that the same head everyone is using? Same as the Z06 with out the light valves? What the cc's of the chamber?

 

Found this on another site.

Casting Number 241
Head: 1997+ LS1 5.7 Litre Passenger Car
Material: Aluminimum
Part Number:
12558806 (1997-98)
12559853 (1999-00)
12564241 (2001-03)
Combustion Chamber Volume: 66.67cc
Compression Ratio: 10.1:1
Intake Port Volume: 200cc
Exhaust Port Volume: 70cc
Intake Valve Diameter: 2.00 inches
Exhaust Valve Diameter: 1.55 inches


Casting Number 243
Head: 2001 LS6 5.7 Litre Passenger Car
Material: Aluminimum
Part Number:
12564243
Combustion Chamber Volume: 64.45cc
Compression Ratio: 10.5:1
Intake Port Volume: 210cc
Exhaust Port Volume: 75cc
Intake Valve Diameter: 2.00 inches
Exhaust Valve Diameter: 1.55 inches

 

they wouldnt be on a 4.8 unless someone switched them....the LS2's also had 243's on them, but without the light weight valves.

you will only find the sodium filled valves on the CTS-V and Z06 vette.