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

 

Nice info, dude!

I've seen all of this before, but not in the same place at once. I think one of the car magazines had this info a while back, but I can't find it now.

 

GM high tech may2003 with Sikora's car on the cover.

 

FYI:

My '02 LQ9 Escalade engine has the #317 castings.. I've yet to see an '02 up that doesn't have the #317 castings.. That includes Escalades and Silverado SSs.. There is no difference between the LQ4 and the LQ9 heads.. The difference is found in the pistons..

 

Yeah, it would be rare to see a car mag compile that much technical info and get it correct.

The 97-98 heads are 806 castings, not 853. The 853 is 99-00 only.

 

thanx for the info fireball. i have a question.
my car turns good times for a cam only (mild cam, full weight), so at a recent event, someone pointed out that my passenger side head has the casting #'s grinded off:



however, on the side of it, right under that shaved section, the following numbers are etched into the head:
9114F9322856
does the above number coincide with an 853 head?

The drivers side has the normal head casting numbers for my 1999 car:


So i guess some people might think i put one LS6 head on the car. but that is ridiculous. Is it possible my car came from the factory with the pass. side head # shaved off? or was this something that jay fisher pontiac did accidentally when they installed my cam and deleted my AIR/EGR?

 

Nice informative post.
Minor corrections, but still relevant:
Casting #933 '97 perimeter bolt 5.7l
Chambers = 69cc
Casting #806 '97-'98 perimeter bolt 5.7l
Chambers = 69cc
Casting #862 and 706 '99 and up 4.8-5.3l trucks
Chambers = 61cc


2MCHPWR:
The passenger side head should have the casting number on the rear corner of the passenger head. Your pics look like the front corner of each head. GM put the casting numbers on the same corner of each casting. The numbers should appear on the front left and right rear head corners.

Richard

 

Pull the header away and if it has "D" shaped exhaust ports, then yes.. you have a LS6 head.

Jay Fisher would not have to grind anything away to remove the AIR/EGR.

 

Thanx Richard! that explains it. the casting number on the passenger side must be under the cowl since the drivers side is on the front of the motor. i knew i wasn't cheating

 

Nobody can be that cheap.. to upgrade ONE head, right?

 

I hope not, that would be wierd

 

Below is what I have. BTW, you stated that the 933 and 806 97-98 LS1 heads have a stock chamber volume of 69cc. I believe that is actually 66.67cc
__________________________________________________ __

Casting Number 806 or 933
LS1 (Perimeter Bolt)
97-98 5.7L Passenger Car and Corvette
Material: Aluminum
Combustion Chamber Volume: 66.67cc
Intake Port Volume: 200cc
Exhaust Port Volume: 70cc
Intake Valve Diameter: 2.00 inches
Exhaust Valve Diameter: 1.55 inches

Casting Number 853 or 241
LS1 (Center Bolt)
99-00 5.7L Passenger Car and Corvette (853)
01+ 5.7L Passenger Car and Corvette (241)
Material: Aluminum
Combustion Chamber Volume: 66.67cc
Intake Port Volume: 200cc
Exhaust Port Volume: 70cc
Intake Valve Diameter: 2.00 inches
Exhaust Valve Diameter: 1.55 inches

Casting Number 243
LS6
01+ 5.7L Corvette
Material: Aluminum
Combustion Chamber Volume: 64.45cc
Intake Port Volume: 210cc
Exhaust Port Volume: 75cc
Intake Valve Diameter: 2.00 inches
Exhaust Valve Diameter: 1.55 inches

Casting Number 706
LM4 / LM7
99+ 5.3L Truck
Material: Aluminum
Combustion Chamber Volume: 61.15cc
Intake Port Volume: 200cc
Exhaust Port Volume: 70cc
Intake Valve Diameter: 1.89 inches
Exhaust Valve Diameter: 1.55 inches

Casting Number 852
LR4
99+ 4.8L Truck
Material: Aluminum
Combustion Chamber Volume: 61.15cc
Intake Port Volume: 200cc
Exhaust Port Volume: 70cc
Intake Valve Diameter: 1.89 inches
Exhaust Valve Diameter: 1.55 inches

Casting Number 317 or 035
LQ9
01+ 6.0L Truck
Material: Aluminum
Combustion Chamber Volume: 71.06cc
Intake Port Volume: 210cc
Exhaust Port Volume: 75cc
Intake Valve Diameter: 2.00 inches
Exhaust Valve Diameter: 1.55 inches

 

Guys maybe you can answer this for me I`m trying to find out what the differance is bettwen the lq9 and lq4 heads? Some say no differance some the lq9 is a low comp. ls6 and the lq4 is a low comp. ls1. I can`t find a straight answer is there a differance or not? please help.

 

There most certainly is a difference!
Your correct in that the LQ9 heads can be considered a low compression LS6 head, however the LR4 or LM7 heads are not low compression LS1 heads. They're small chamber truck heads and will boost compression in LS1 engines, but remember they have only 1.890" intake valves in stock trim. The valve seats can be remachined to accomodate 2.02" intake valves and 1.57" exhaust valves.

Hope this helps,

Richard

 

Is the lr4 head the same as the lq4 Becase everything that i`ve read says that the lq4 has the same valve sizes, Intake and exhaust port volume and chamber size as the lq9?

 

Guys maybe you can answer this for me I`m trying to find out what the differance is bettwen the ls6 heads and the ls1 heads i gout these heads from the mti and i dont know if these head ar ls6 or ls1.
thanks for help...

 

ls6 heads have D shaped exhaust ports and the ls1 has round exhaust ports.

 

thanks man i will see that in my heads ..

 

Hey great info in here! Thanks for helping us number challenged people out.
Question, I am upgrading a 5.3L truck block with 241 heads and an 02 Z06 cam. I see that the head gaskets are different for the 01 and the 02+ 241 heads. I know there is a date code on the heads somewhere. Is the difference in the head or block? The engine is from an 01' model and I THINK the heads are 02'. Thanks for any help!

 

"I see that the head gaskets are different for the 01 and the 02+ 241 heads. I know there is a date code on the heads somewhere"

Not always true. The graphite head gaskets were used on all year models except the 2002. In 2002 [some] of the gaskets were changed to the "Multi-layer" type .... But, not all got these .... I still think that the graphite gaskets are the best overall .... Just my opinion.
__________________________________________________ _____________

"I know there is a date code on the heads somewhere. Is the difference in the head or block?"

Don't know about the block, but you won't find anyone of the late model LS1 heads any better than the rest. A good porting job makes them all equal.