Starting Hummer H3 Swap-LQ4 vs. LS2 engine questions
11-19-2007, 10:55 AM
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Starting Hummer H3 Swap-LQ4 vs. LS2 engine questions OK, I tested the Hummer H3 Alpha and found that it wasn't much more gutsy than the stock 3.5 inline (300hp vs 245hp---despite criticism, it's the little engine that could). I have decided to swap for a bigger v8. This will be my easiest swap to date, since I am going GM into GM. I found a Hummer H2 drivetrain with a 60,000 mile Lq4 in great condition and a 4l65e tranny and transfer case. Drive shafts, exhaust stuff came with it.
My dilemma is this: I accidentally won an LS2 crate motor auction on Ebay for $4500 ( I guess in the back of my mind I wanted to win...I thought someone was going to outbid me). So now I have both engines. I don't think the truck engine would have to be rebuilt as I expect it to last for at least a couple of hundreds of miles. It has the harness intact and would drop right in (although I think I'll have the harness simplified by Current or Speartech) and think it's in an H2.
Now, if I used the LS2, it would be brand spanking new, weigh less (although I don't think the block actually weighs that much less, maybe 50 pounds?). I would for sure get a standalone harness. Minuses? Well 400hp in a vehicle with one of the highest production centers of gravity in history does not sound like a good idea (but fun
).
Which one would you go with?
Also, the H2's front diff is on the driver's side and the H3's is on the passenger's side. The transfer case is therefore on the wrong side. Is it possible to get this flipped around? Otherwise I'll have to use my H3's tranny and beef it up (it's a 4l60e made for a 5 cylinder, after all)
My dilemma is this: I accidentally won an LS2 crate motor auction on Ebay for $4500 ( I guess in the back of my mind I wanted to win...I thought someone was going to outbid me). So now I have both engines. I don't think the truck engine would have to be rebuilt as I expect it to last for at least a couple of hundreds of miles. It has the harness intact and would drop right in (although I think I'll have the harness simplified by Current or Speartech) and think it's in an H2.
Now, if I used the LS2, it would be brand spanking new, weigh less (although I don't think the block actually weighs that much less, maybe 50 pounds?). I would for sure get a standalone harness. Minuses? Well 400hp in a vehicle with one of the highest production centers of gravity in history does not sound like a good idea (but fun
). Which one would you go with?
Also, the H2's front diff is on the driver's side and the H3's is on the passenger's side. The transfer case is therefore on the wrong side. Is it possible to get this flipped around? Otherwise I'll have to use my H3's tranny and beef it up (it's a 4l60e made for a 5 cylinder, after all)
11-19-2007, 11:17 AM
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Never mind on the transfer case/tranny question. I'm not an auto tranny guy, so I know very little about them. I called around and found that you can't flip over a transfer case (duh!). Looks like I'll be using the H3's tranny/transfer case. I've been assured by a tranny shop that it will hold up to an LS2 (the auto corvette's have them after all!)
11-19-2007, 07:13 PM
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Why would you get a stand alone harness for the LS2 swap? I am sure Current can make you one that will plug in and make everything work without the hassles of dealing with a stand alone harness on that setup. They have done a couple on newer Colorados which are pretty similar to the H3 Hummer.
11-19-2007, 09:46 PM
#5
Since Hummer is now installing 5.3's in Hummer H3's, this will be an easy swap using factory parts:
You can buy H3 5.3 exhaust manifolds and oil pan that will fit perfectly direct from GM.
At the SEMA show there was a real nice one with an LS7 engine!
H3 5.3 Alpha oil pan
You can buy H3 5.3 exhaust manifolds and oil pan that will fit perfectly direct from GM.
At the SEMA show there was a real nice one with an LS7 engine!
H3 5.3 Alpha oil pan
Last edited by philntx; 11-19-2007 at 09:54 PM.
11-19-2007, 10:17 PM
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Why would you get a stand alone harness for the LS2 swap? I am sure Current can make you one that will plug in and make everything work without the hassles of dealing with a stand alone harness on that setup. They have done a couple on newer Colorados which are pretty similar to the H3 Hummer.
You are right. I know they have done a lot of work with Colorados, so they should be able to literally hook me up.
