LQ4 & LQ9, What is the differences between the two
#21
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i have a stock fbody t56 on 2004 lq9 everything bolts right up and i have an ls6 intake and all the stock fbody acs. as far as ls2 heads go im not sure there quite the same but i have stock ls1 heads on my lq9 to up the comp. to 11:2:1 but other wise a stock interals including cam.
#22
thank you very much to the guy who posted this thread and to the guy who posted the above information. I have a 2007 60 lq4 and I was getting on tonite to ask a question regarding parts interchange between my engine and ls blocks. If I am understanding correctly I will be able to use parts like intake, heads, water pump,ect. from any ls2 engine. Will I be able to use an earlier model 5 or 6 speed manual like out of out of an 99 or 2000 camaro behind my engine? please post any helpful responses.
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Wow, a lot of misinformed responses. A quick search would have netted you the correct answer, but to clear the air with facts:
LQ4 and LQ9 are Gen3 engines, not Gen4 (like the LS2, LS3, L76), due to the location of the cam sensor and knock sensors.
LQ4 debuted in 1999
Displacement was/is 6.0L
1999-2000 had iron heads
1999-2000 had a crank adapter to mate the LQ4 with the 4L80 trans (not LS1 compatible)
Compression ratio was 9.5:1
Bloack was Iron
In 2001 the LQ9 was introduced
Both the LQ4 and LQ9 shared the iron block and new 317 heads (similar as the 243, but with larger 76cc chambers), hence both are 6.0L
The LQ9 had 10.4:1 compression ratio, versus the LQ4's 9.5:1
No longer did either 6.0L require the crank adapter for the trans, now works with LSx applications.
In 2004/5 6.0L recieved improved rod design
In 2005 the LS2 block was introduced
It is essentially the LQ9 with an aluminum block
LQ9 still offer with an iron block.
LQ4 and LQ9 are Gen3 engines, not Gen4 (like the LS2, LS3, L76), due to the location of the cam sensor and knock sensors.
LQ4 debuted in 1999
Displacement was/is 6.0L
1999-2000 had iron heads
1999-2000 had a crank adapter to mate the LQ4 with the 4L80 trans (not LS1 compatible)
Compression ratio was 9.5:1
Bloack was Iron
In 2001 the LQ9 was introduced
Both the LQ4 and LQ9 shared the iron block and new 317 heads (similar as the 243, but with larger 76cc chambers), hence both are 6.0L
The LQ9 had 10.4:1 compression ratio, versus the LQ4's 9.5:1
No longer did either 6.0L require the crank adapter for the trans, now works with LSx applications.
In 2004/5 6.0L recieved improved rod design
In 2005 the LS2 block was introduced
It is essentially the LQ9 with an aluminum block
LQ9 still offer with an iron block.
#30
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wrong, they're both 364
The other difference I don't see pointed out here but sorta alluded to is the pistons specific difference...not just compression ratio...the LQ9 pistons have floating pins, the LQ4 pistons are pressed into the rods like LS1's. I believe there is also an anti-friction coating on the skirts of the LQ9 pistons that isn't on the LQ4 pistons.
I see a lot of people saying they're having trouble finding LQ9 heads...they're the exact same 317 castings as the LQ4...and they're in BAJILLIONS of pickup trucks, vans and work trucks with the 6.0 liter...I can't go to a junkyard without finding 317 heads...great heads, but not rare at all.
The other difference I don't see pointed out here but sorta alluded to is the pistons specific difference...not just compression ratio...the LQ9 pistons have floating pins, the LQ4 pistons are pressed into the rods like LS1's. I believe there is also an anti-friction coating on the skirts of the LQ9 pistons that isn't on the LQ4 pistons.
I see a lot of people saying they're having trouble finding LQ9 heads...they're the exact same 317 castings as the LQ4...and they're in BAJILLIONS of pickup trucks, vans and work trucks with the 6.0 liter...I can't go to a junkyard without finding 317 heads...great heads, but not rare at all.
#31
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wrong, they're both 364
The other difference I don't see pointed out here but sorta alluded to is the pistons specific difference...not just compression ratio...the LQ9 pistons have floating pins, the LQ4 pistons are pressed into the rods like LS1's. I believe there is also an anti-friction coating on the skirts of the LQ9 pistons that isn't on the LQ4 pistons.
I see a lot of people saying they're having trouble finding LQ9 heads...they're the exact same 317 castings as the LQ4...and they're in BAJILLIONS of pickup trucks, vans and work trucks with the 6.0 liter...I can't go to a junkyard without finding 317 heads...great heads, but not rare at all.
The other difference I don't see pointed out here but sorta alluded to is the pistons specific difference...not just compression ratio...the LQ9 pistons have floating pins, the LQ4 pistons are pressed into the rods like LS1's. I believe there is also an anti-friction coating on the skirts of the LQ9 pistons that isn't on the LQ4 pistons.
I see a lot of people saying they're having trouble finding LQ9 heads...they're the exact same 317 castings as the LQ4...and they're in BAJILLIONS of pickup trucks, vans and work trucks with the 6.0 liter...I can't go to a junkyard without finding 317 heads...great heads, but not rare at all.
#32
wrong, they're both 364
The other difference I don't see pointed out here but sorta alluded to is the pistons specific difference...not just compression ratio...the LQ9 pistons have floating pins, the LQ4 pistons are pressed into the rods like LS1's. I believe there is also an anti-friction coating on the skirts of the LQ9 pistons that isn't on the LQ4 pistons.
I see a lot of people saying they're having trouble finding LQ9 heads...they're the exact same 317 castings as the LQ4...and they're in BAJILLIONS of pickup trucks, vans and work trucks with the 6.0 liter...I can't go to a junkyard without finding 317 heads...great heads, but not rare at all.
The other difference I don't see pointed out here but sorta alluded to is the pistons specific difference...not just compression ratio...the LQ9 pistons have floating pins, the LQ4 pistons are pressed into the rods like LS1's. I believe there is also an anti-friction coating on the skirts of the LQ9 pistons that isn't on the LQ4 pistons.
I see a lot of people saying they're having trouble finding LQ9 heads...they're the exact same 317 castings as the LQ4...and they're in BAJILLIONS of pickup trucks, vans and work trucks with the 6.0 liter...I can't go to a junkyard without finding 317 heads...great heads, but not rare at all.
not trying to start **** but pick up a copy of how to build high performance ls1/ls6 v-8's... turn to page 25 and look on the bottom in the red box says exactly what i posted in here... if im wrong oh well but thats just what i read
#33
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benefit of a floating pin...I don't think I'm qualified to answer that, just pointing out that the LQ9 has them and the LQ4 doesn't...maybe a reputable engine builder will comment on that...I tend to think it's a friction/stress/side loading thing, but like I said, I am not really qualified to answer it
#34
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if that book does indeed say that, it is a typo. the LS2, LQ4, and LQ9 are all 6.0 L engines, or 364 cubic inches. the differences between the three are the casting material, heads, and compression, not cubic inches.
#35
#36
must be a typo in the book...or you're looking at specs for a 6.2 liter maybe (I don't know displacement of the new 6.2 in cublc inches)...the LQ4 and LQ9 are both 364 cubic inches, same crank and bore = same displacement...the pistons are different, as I noted...but they're the same diameter
#37
It was just stated above that the heads are the same 317 heads as the LQ4. What gives? Any difference in the PCM tune?
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I was always wondering what the difference was between the LQ4/LQ9 myself, and I really didn't find any noticeable differences that would make one better than the other. I have the LQ4 w/317 heads and the FAST 90MM Intake/TB. Only thing is, the compression is higher than most LQ4's (10.3:1). The guy that built it set it up for forced induction.
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I was always wondering what the difference was between the LQ4/LQ9 myself, and I really didn't find any noticeable differences that would make one better than the other. I have the LQ4 w/317 heads and the FAST 90MM Intake/TB. Only thing is, the compression is higher than most LQ4's (10.3:1). The guy that built it set it up for forced induction.
DM