Im wanting to shed a lil weight and currently looking into putting a aluminum LS2 in my 03 rcsb, stock short block with heads and nitrous cam. Im wondering if there are any major wiring differences to make this work or is it better to just build off a LQ9 6.0?

 

Unless you picked up one of the earlier '05 model motors or an '06 Trailblazer SS LS2, the vast majority of the LS2’s have the 58 tooth reluctor wheel and it will either have to be swapped out for a 24 tooth wheel like you currently have or use one of the adapter boxes from Lingenfelter. Yes the knock sensors are on the side of the motor and the camshaft position sensor is in the timing-chain cover on the LS2’s, but extension harnesses are available for them. You will also need to swap out the knock sensors for some that are compatible with your ECM, but there again it is all doable. The LQ9 would be a more straightforward swap no doubt, but if you’re set on loosing the weight, then the LQ9 just won’t do it for you. They are equally capable though, however, the LQ9 is a stronger foundation plain and simple if you have further ideas down the road, but most folks wouldn’t ever stress the aluminum block hard enough to be scared of it.

 

Good info. So your saying I need to be shopping for a TBSS motor and I wont run into all those problems? As far as the strength of the aluminim block, I think they are alot stronger than people give them credit. Granted if i was planning on running 8s and was running a crazy amount of boost or alot of nitrous the LQ9 block would be the way to go. Im looking for a streetable truck that runs mid 11s on motor and can handle at most 200 shot of juice and get me in the 10s every now and then at the track.

 

If it has a black crank sensor you're good to go. GTO's also ran the 24x reluctor wheels

 

Just like hirdlej said, look for a motor with the black crankshaft position sensor. And like I said, start looking for either a ’05 model LS2 or a ’06 Trailblazer LS2 and then check out the sensor to help put your mind to rest. You will still run into all the other issues with the relocation of the sensors, but the relocation harnesses are readily available. You will end up needing to change the oil pan from whatever motor you pick up over to a truck pan and when you do, you can make one last check to verify the type of reluctor wheel, but unless someone was unscrupulous or just plain mistakenly put in the wrong sensor, if it’s black your good to go. Also just so you know the difference, in case you haven’t already came across the info, the crankshaft position sensor for a motor equipped with a 58 tooth reluctor wheel will be colored gray.

 

Thanks guys, damn good info, this is just what i needed to now. And yeah i had planned on pulling the oil pan anyway to put ARP rod bolts in so ill just go back with my original 4.8 pan.

 

Assume the TBSS pan will not bolt in ?

 

Unfortunately not, it's a front sump.

VS a Truck Pan

Here is a very good link to Tech that has pictures, part numbers and dimensions on most if not all available LSX oil pans: https://ls1tech.com/forums/conversio...-oil-pans.html