Lq4/lq9
01-29-2005, 02:02 PM
#11
The 02-04 LQ4 and LQ9 heads have the same combustion chamber size (71cc), same intake/exhaust port volume (210/75), same casting number (12562317), same machined numbers (12562318) and same final assembly numbers (12565363).
There is a final assemby number of 12565364 for the LQ4 heads which is good for the KL5 natural gas engine.
The LQx heads were designed straight from the LS6 heads, as they all share the same intake and exhaust ports.
I can find no differences between the LQ4 and LQ9 heads, other than the fact the 99-01 LQ4 heads had different part numbers. But the LQ9 was not offered during that time period.
There is a final assemby number of 12565364 for the LQ4 heads which is good for the KL5 natural gas engine.
The LQx heads were designed straight from the LS6 heads, as they all share the same intake and exhaust ports.
I can find no differences between the LQ4 and LQ9 heads, other than the fact the 99-01 LQ4 heads had different part numbers. But the LQ9 was not offered during that time period.
01-29-2005, 04:11 PM
#12
Originally Posted by nativetexan
If you are choosing between the 6.0 engines, most folks seem to prefer to boost the LQ4 as opposed to the LQ9. The LQ4 is a lower compression engine which allows them to run more boost. Someone shoot me if I'm wrong. Also the LQ4 should be a little easier to find.
Head: 1999-2000, LQ4 6.0-Liter 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 Diamter: 2.00-inches
Exhaust Valve Diamter: 1.55-inches
______________________________
Head: 2001+, LQ4 6.0-Liter Truck
Material: Aluminum
Part number: 12562317
Combustion Chamber Volume: 71.06cc
Compression Ratio: 9.4:1
Intake Port Volume: 210cc
Exhaust Port Volume: 75cc
Intake Valve Diamter: 2.00-inches
Exhaust Valve Diamter: 1.55-inches
________________________________
Head: 2002+, LQ9 6.0-Liter Truck
Material: Aluminum
Part number: 12572035
Combustion Chamber Volume: 71.06cc
Compression Ratio: 10:1
Intake Port Volume: 210cc
Exhaust Port Volume: 75cc
Intake Valve Diamter: 2.00-inches
Exhaust Valve Diamter: 1.55-inches
01-29-2005, 04:20 PM
#13
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Originally Posted by snakeoiler
I can find no differences between the LQ4 and LQ9 heads, other than the fact the 99-01 LQ4 heads had different part numbers. But the LQ9 was not offered during that time period.
Sorry I see Jared already mentioned the cast iron heads.
01-29-2005, 04:27 PM
#14
Originally Posted by Mort
Those 99-01 LQ4 heads with the different part numbers are probably the older cast iron heads. The current heads are aluminum but the 6.0 had cast iron heads for a while before beng upgraded to the aluminum ones.
Sorry I see Jared already mentioned the cast iron heads.
Sorry I see Jared already mentioned the cast iron heads.
I hope all that info is correct. I did a bit of searching for the head specs.
01-29-2005, 04:28 PM
#15
Originally Posted by Snake Eater
Why on earth would you need beefier rods in a LQ9? All the LS rods are forged powder rods, and we all know an LQ4 bottom end can hold over 800hp at the motor.
Maybe parish should have pulled the pan on the last 6.0 to see if there was any unusual wear with all the abuse.
Maybe parish should have pulled the pan on the last 6.0 to see if there was any unusual wear with all the abuse.
01-29-2005, 06:28 PM
#16
Hey Jared,
For the LQ4's, you listed the casting numbers as the part number (these correspond with the same casting numbers that I have), but where did you get that number you listed for the LQ9? The only numbers I have for the LQ9 I listed above in a previous post and that one was not any of them.
For the LQ4's, you listed the casting numbers as the part number (these correspond with the same casting numbers that I have), but where did you get that number you listed for the LQ9? The only numbers I have for the LQ9 I listed above in a previous post and that one was not any of them.
01-30-2005, 11:41 PM
#17
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Sorry guys I didn't really know what I was talking about that was just what I heard You know how that goes. Does anyone have the specs on the new C6 heads
01-31-2005, 09:57 AM
#18
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Casting number - passenger side, towards front of truck. (If I'm remembering right).
I think 317/035 heads are identical spec wise.... It was all in they way they were made. (Something to the effect of one being sand cast, and the other something else).
I'm quite sure the 035's were the least common ones - while the 317's (that I have) were the more common/cheaper ones.
I think 317/035 heads are identical spec wise.... It was all in they way they were made. (Something to the effect of one being sand cast, and the other something else).
I'm quite sure the 035's were the least common ones - while the 317's (that I have) were the more common/cheaper ones.
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