So, a few months back I was able to pick up a 2008 CTS4 dirt cheap. The original 3.6 had 200k on it and a destroyed valve train as a result of a timing chain failure. The dream of owning a CTS-V has long been in my head, but financially it’s not in the cards. when I saw this CTS4 come up for sale the ideas stated coming and I pulled the trigger on it. I figured it couldn’t be that hard to put an LS into something that already had version produced from factory.
after getting the car the tired old 3.6L was pulled out in the same weekend.
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From there the research and hunt for a donor engine began. One of the first things I realized was the AWD front cradle wasn’t going to work if I wanted to drop the LS right in to the factory mounting spots of a V. I was able to get my hands on a RWD/V cradle Out of a local junk yard( I took some measurements and everything is going to bolt Up perfectly). About the same time I found the perfect donor vehicle for the LS. A 2001 Silverado 2500 RWD 6.0L LQ4 paired to a 4L80 that was running and driving with only 85k on it.
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This was more than ideal because I could see it run and have plenty of extra parts to sell off to help fund the build. The 6.0 is going to get alittle love before being transplanted into my CTS. The plan for it now is a mild build with 0.040 cosmetics head gaskets, lifters, PAC trunion and spring kit, a sloppy stage 2 cam, and some other odds and ends.
Things start to slow down a bit now. I was having trouble figuring out some ways to go about things on this build that is until I found these lovey forums. Did some digging and came across the legend of a man who did this swap already @Big_kid. I looked through his swap forum and it was a huge help for a lot of the Process even tho there’s some differences between our swaps. Right now I’m at a bit of a stand still on parts due to me being stationed in Alaska, so parts tend to take awhile to get here…..
While I’m waiting on parts I want to get some other details of swap figured out. Wiring is a huge question for me and I want to take
the best route possible. Another question is the fuel system. Am I able to run the stock pump that’s on it now? I would assume the 6.0L is gonna be a bit more thirsty then the stock 3.6L. Front accessories are another big one, what alternator, water pump, etc should I run? Looking forward to hearing from you guys and keeping you updated on the progress!!
after getting the car the tired old 3.6L was pulled out in the same weekend.
From there the research and hunt for a donor engine began. One of the first things I realized was the AWD front cradle wasn’t going to work if I wanted to drop the LS right in to the factory mounting spots of a V. I was able to get my hands on a RWD/V cradle Out of a local junk yard( I took some measurements and everything is going to bolt Up perfectly). About the same time I found the perfect donor vehicle for the LS. A 2001 Silverado 2500 RWD 6.0L LQ4 paired to a 4L80 that was running and driving with only 85k on it.
This was more than ideal because I could see it run and have plenty of extra parts to sell off to help fund the build. The 6.0 is going to get alittle love before being transplanted into my CTS. The plan for it now is a mild build with 0.040 cosmetics head gaskets, lifters, PAC trunion and spring kit, a sloppy stage 2 cam, and some other odds and ends.
Things start to slow down a bit now. I was having trouble figuring out some ways to go about things on this build that is until I found these lovey forums. Did some digging and came across the legend of a man who did this swap already @Big_kid. I looked through his swap forum and it was a huge help for a lot of the Process even tho there’s some differences between our swaps. Right now I’m at a bit of a stand still on parts due to me being stationed in Alaska, so parts tend to take awhile to get here…..
While I’m waiting on parts I want to get some other details of swap figured out. Wiring is a huge question for me and I want to take
the best route possible. Another question is the fuel system. Am I able to run the stock pump that’s on it now? I would assume the 6.0L is gonna be a bit more thirsty then the stock 3.6L. Front accessories are another big one, what alternator, water pump, etc should I run? Looking forward to hearing from you guys and keeping you updated on the progress!!
