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LQ9, LQ4 how to tell?

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Old 09-13-2005, 12:18 PM
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Default LQ9, LQ4 how to tell?

Im going to look at a 6.0 to replace my 5.3. I tole the place I was looking for a 6lH.O. They said it came out of a Denalli. Do they know something I dont? How can I visually tell teh difference? Or if it is the LQ4 would milling the heads .023 or .030 bring my compression up to that of a LQ9? That way if I ever did (which I'm sure I wont) decide to go FI I could just swap heads? Thanks mostly I'm wondering how to tell a difference.
Old 09-13-2005, 01:36 PM
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Originally Posted by white1
Im going to look at a 6.0 to replace my 5.3. I tole the place I was looking for a 6lH.O. They said it came out of a Denalli. Do they know something I dont? How can I visually tell teh difference? Or if it is the LQ4 would milling the heads .023 or .030 bring my compression up to that of a LQ9? That way if I ever did (which I'm sure I wont) decide to go FI I could just swap heads? Thanks mostly I'm wondering how to tell a difference.
Not sure how to tell externally, but the LQ4 has dished pistons and the LQ9 has flat tops. I guess if you could get a peek in one of the spark plug holes with a lighted scope you could tell.
Old 09-13-2005, 01:44 PM
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yeah with the motor still together good luck. so far as i know the pistons is the only way to visually tell the difference.

i don't think the denali's came with the lq9 though. pretty sure lq9 was escalade and ss truck only
Old 09-13-2005, 01:50 PM
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Originally Posted by crazyidiot4.8
yeah with the motor still together good luck. so far as i know the pistons is the only way to visually tell the difference.

i don't think the denali's came with the lq9 though. pretty sure lq9 was escalade and ss truck only

That's what I thought too...just tell them you're looking for a replacement motor for your 03 Escalade and you'll get the right one. When I was looking for an LQ9 seriously I called a bunch of places, some didn't know the difference between the two, and one guy even told me that they didn't have any big blocks. I told him it was a small block, he disagreed, blah blah...the point is, a lot of these places don't know what they are talking about.
Old 09-13-2005, 02:29 PM
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Wonder how much I would have to shave the heads to get the compression the same as a LQ9? If I have to pull the heads a little P&P may be in order too
Old 09-13-2005, 04:32 PM
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if he's calling the place i told him to call byron knows the difference....
Old 09-13-2005, 07:14 PM
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Tony, whats up with the "other one" you know about?
Old 09-13-2005, 08:46 PM
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Originally Posted by white1
Wonder how much I would have to shave the heads to get the compression the same as a LQ9?
More than what is safe to run.
Old 09-13-2005, 11:53 PM
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Old 09-13-2005, 11:57 PM
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Originally Posted by white1
Dude, I tried before I put my LQ4 in. It just would have taken too much to get the CR up. You could mill down 30 thou and use a thinner FelPro gasket and get the comp to near 10.8 or so.


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