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Old Feb 7, 2009 | 07:46 AM
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Default Help with engine questions

I know this is waaaaaaaaaaaaaaaaay off topic, but I know there are some regulars around here that can help me out with my question.

Why is there a pretty significant power difference between the:
Chevrolet HD 2500 with the 6.0L ~360hp
Suburban 2500 with the 6.0L ~330 hp

They are both mated to the same transmission, I am trying to figure out what the deal is. . . . .
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Old Feb 7, 2009 | 08:26 AM
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Most likely, detuning. As the Suburban is more of a people hauller than a work type truck. The same can be said about the Tahoe and Yukon, why does the Yukon get more power out of the supposed same engine as the Tahoe? This is an interesting question, and one I don't fully understand the reasoning behind. But my best guess is detuning! Do you have engine codes, if the codes are different than that would explain a lot. As then there is obviuosly dfferent internals.
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Old Feb 7, 2009 | 03:42 PM
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my truck has the dished pistons. the one with the flat pistons is higher compression and more hp, but doesnt work out so well with forced induction. theres a vortec 6.0 and a vortec max 6.0. i just have to deal with less hp and use lower octane gas.
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Old Feb 7, 2009 | 07:36 PM
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The LQ9 has a higher CR and heads modeled after LS6 heads. Not tottally certain of a cam difference. Later model LQ4's in 3/4tons have 345hp too now IIRC.
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Old Feb 7, 2009 | 07:52 PM
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You are right, the 2009 sub is rated at 352 now:
The Vortec 6.0L standard in three-quarter-ton models pumps out a prodigious 352 horsepower and 382 lb.-ft. of torque.
THe HD truck states
Vortec 6.0L V8 engine (HD) features:

* Thundering 360 hp @ 5600 rpm (322 hp @ 4400 rpm in 3500HD Big Dooley models)
* 380 lb.-ft. of torque @ 4200 rpm
Interestingly enough the 1/2 ton now offers an all aluminum block with 366hp
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Old Feb 7, 2009 | 08:42 PM
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Originally Posted by eddiemoney
You are right, the 2009 sub is rated at 352 now:


THe HD truck states

Interestingly enough the 1/2 ton now offers an all aluminum block with 366hp
You can even get an L92 with 400hp now too in crew cab half tons and tahoes... just not reserved for the denali's/escalades anymore.
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Old Feb 7, 2009 | 10:35 PM
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Originally Posted by BADDLS1SS
You can even get an L92 with 400hp now too in crew cab half tons and tahoes... just not reserved for the denali's/escalades anymore.
L92 is a 6.2L, based on the LS3, with the big intake valve heads, kinda like the L99 in the new auto camaros...
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Old Feb 8, 2009 | 07:44 AM
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Originally Posted by someday
L92 is a 6.2L, based on the LS3, with the big intake valve heads, kinda like the L99 in the new auto camaros...
right... just stating that its gonna be replacing the 6.0l vortec max option on 09+ ltz trucks. Prob muddy'ed the water with this.
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