RAMnGO

ok i have some pics of my heads that i put on my car and i would like to know if you look at a 5.7l head and a 5.3l head can you tell a difference between them by the combustion chambers alone?? i've got myself into quite a scenario here and i need to start with the heads...

BergerMan

Check the casting #'s, They will tell you EXACTLY what you have. It is a 3 digit # cast into the corner of each head.


Here is a list of a few casting #'s:
853 97-00 aluminum 5.7
241 01-03 aluminum 5.7
243 LS6 aluminum 5.7
852 and 706 99 and up 4.8-5.3 truck heads
873 99-00 LQ4 6.0 iron heads
317 01 and up LQ4 6.0 aluminum heads
035 02 and up LQ9 6.0 aluminum heads


Even more info:

Casting Number 241
Head: 1997+ LS1 5.7 Litre Passenger Car
Material: Aluminimum
Part Number:
12559853 (1997-98)
12559853 (1999-00) (not sure why same PN)
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

Casting Number 706
Head: 1999+ LR4 4.8 Litre Truck
1999+ LM4 /LM7 5.3 Litre Truck
Material: Aluminimum
Part Number:
12559852
12561706
Combustion Chamber Volume: 61.15cc
Compression Ratio: 9.5:1
Intake Port Volume: 200cc
Exhaust Port Volume: 70cc
Intake Valve Diameter: 1.89 inches
Exhaust Valve Diameter: 1.55 inches

Casting Number 373
Head: 1999-2000 LQ4 6.0 Litre Truck
Material: Cast Iron
Part Number:
12561873
Combustion Chamber Volume: 71.06cc
Compression Ratio: 9.5:1
Intake Port Volume: 210cc
Exhaust Port Volume: 75cc
Intake Valve Diameter: 2.00 inches
Exhaust Valve Diameter: 1.55 inches

Casting Number 317
Head: 2001+ LQ4 6.0 Litre Truck
Material: Aluminimum
Part Number:
12572035
Combustion Chamber Volume: 71.06cc
Compression Ratio: 10:1
Intake Port Volume: 210cc
Exhaust Port Volume: 75cc
Intake Valve Diameter: 2.00 inches
Exhaust Valve Diameter: 1.55 inches

Paul F

iTrader: (2)

Also on the underside of the head above the CC it will have 4.8 or 5.7.

Visceral

iTrader: (1)

In that table either the 373 or the 317 compression ratio is wrong, since the CC's are the same size for the same motor.

chris

BergerMan

Yup, the cc's are the same, its the pistons that are different which raised the compression to 10:1 in 2001+. Combustion chamber volume isn't the only variable in calcualting the compression ratio.

RAMnGO

ok first off i have pics of the new heads combustion chamber...the number on the head is 862...when i looked at my old heads and compared them to the new heads combustion chambers i mean ray charles could have seen the difference...and thats where i'm gonna stop....

BergerMan

RAMnGO, I'm still not sure what you are looking for here so send me a message and maybe I can help you out with your problem.