Racefan1331

I'm new here and new to the LS platform in general. I recently bought a 2011 ccsb silverado with an LC9 engine. The truck has 220xxx miles on it. I'm looking to start accumulating parts to build a replacement engine for it when the time comes. I found a really good deal on an LQ4 block. I know that it's a gen 3 and that the knock sensors would need replaced and a gen 3 uses a 24 tooth reluctor wheel. Since this block currently does not have a crank in it, if I purchase a crank with a 58 tooth reluctor, and relocate the knock sensors, is there anything else that would keep me from using it? Also, I would be reusing the existing timing cover setup and obviously tuning out the DOD/AFM. Any input would be appreciated. I tried to search but only found articles on using a gen 4 in an older vehicle. Thanks.

jtphelps289

iTrader: (1)

I did the same thing that's basically all you need to make provisions for is the reluctor wheel the knock sensors and You'll need to change the timing to the correct 4x setup so the CPU sees everything correctly then your good to go as far as the knock sensors I believe there are harness extensions so you can run them from the side to under the manifold or you can do like I had mine done and just drill and tap them to the side like a gen4 good luck with the swap

biggdiffs

Gen 4 LS into gen 3?? I have an 05 Envoy 5.3 that i put an 08 6.0 into.... Kept the DOD.. 20+ mpg, so---Why swap cranks? thats big money and time.... One of lingenfelter 's biggest selling items is this little adapter box, turns 58x and 4x Reluctor to 24x and 1x Reluctor. Think it needs a 10 amp fuse, and a ground. You dont buy the new sensors, all the seals, and gaskets. Drilled 2 pilot holes to mount it right to the frame. That's it--
My advice is buy this for 250bucks and you are driving it tomorrow. Buy+ Nothing+ else--- all plugs fit right, but might need some silicone to be water tight. I dashed through a big puddle popped a fuse, had to pull all the plugs apart dry with WD, and then grab a new10a from another accessory. Rolling now 4yr, 75k miles.

ZO6Ted

He's wanting gen 3 to gen 4. But thanks for the info I didn't realize you could so easily do gen 4 to gen 3. Bet that little Envoy runs great.

biggdiffs

O right, yeah--. I totally misread it. install the knock sensors on the sides, just smooth off the casting numbers in between the webs, drill and tap 8mm 1.25 by dip tube . The one side has a little protruding boss you mught try the general area. I once saw a guys turbo rig- he put knock sensors on the side of the head on a long threaded nut / rod arrangement. They stick out like near 2" between the headers.

swathdiver

Sell it for a profit and stick with Gen IV architecture and strength. LY6/L96, L76, L9H/L93/L94 if you want cubes. Stock 6.2s are 400 HP stock.

ssdungeon

iTrader: (23)

Hey I am doing the same thing 2007 TBSS getting an lq4 old gen 3. I had it built with the 58x reluctor so im fine there. Im swapping over everything from my LS2.
I have 2 questions.
1. Did you guys use the long black gen 3 sensor or did you use the shorter grey crank sensor in the back of the block? I am assuming I will need the shorter grey one since the pigtails are slightly different. I pick up the block tomorrow so Im not looking at it right now.
2. I dont see any boss to tap on the block when I stopped by the shop earlier today. I was thinking about welding a nut on the side of the block and screw the sensor in. Can someone post pics of what you guys ended up doing? I know this thread is from the dead but im ready to get my truck back on the road.

arthursc2

iTrader: (5)

you will need to use the gen4 cam sensor and you'll have to put it in the timing cover, like the LS2 probably was

Do not weld the block. Carbon content is super high, and a nuts are usually hardened as well, you will have a very brittle weld that wont last long, at all (especially under vibration). There are several blank bosses on the sides of the block you can drill and tap, or you can enlarge some existing holes to take the larger, more coarse thread of the gen4 sensor

1FastBrick

iTrader: (17)

The rear crank sensor location did not change. Only the sensor and the reluctor wheel changed. Black is 24X and Grey is 58X.

The cam timing sensor and gear location changed. The long black one to refer to went in to the top rear of the block on Gen3 and on Gen4 it was moved to the front timing cover and you need the correct corresponding cam gear for your application.

chevykev

Sorry to hijack but putting an early 2000 402/6.0 lq4 in my gen 4 08 truck. My question is can I run the gen 3 knock sensors in the valley with the gen 4 harness is there a pigtail out there for my application? I’ll run the front timing cover and everything from my 5.3 to this engine so the sensors and everything I’m not worried I just want to make sure the sensors and harness will plug and play with same connectors? I know knock sensors between the generations are different and location wise different but I’m using gen 3 valley knocks and not drilling the block. So what are my options?