L84 Engine in L83 Truck (Dod Deleted)

aapstealth · February 20, 2024

Hey Everybody long time lurker 1st time posting. I currently have a 2015 5.3 Ecotec with an On3 turbo Set up. The truck is doing well but I wanted to get a motor on a stand to start building. Scored a great deal on what was supposed to be a 2018 L83 but it turned out to be a 2020 L84. I've done some research on my end but wanted to get reassurance from those with more knowledge.
When it comes to the Long blocks are these engines the same? I know the front accessories changed on the L84 but it seems I could bolt everything from my L83 onto the L84. They moved the dip stick and removed the vacuum pump. The heads seem to have the same part numbers, as do the HPFP, Injectors, intake manifold etc.
I did see the L84 has a different DOD delete kit and I have heard mixed reviews on if a l83 DOD deleted cam IE Texas speed stage 1 or GDP Cam would work on an L84. If the long blocks are the same I am not sure why one would have a different camshaft.
For the build I am not going crazy simply doing a DOD delete stage 1 cam with a 10-20% Fuel lobe increase and possibly a bottom end refresh pending what I find on the tear down.
Also some information on my current set up if needed. On3 Turbo set up with upgraded 76mm Oil less comp turbo, currently on 6psi 93 pump making 550whp. Built 900hp capable 6l80e with Billet Stock speed stall convertor. I am content with the power and dont have any intention of pushing more boost if the stage 1 cam adds some power great but overall 550-600whp is plenty for me. From the research I've done it seems the stock bottom end can handle the power (Hopefully I don't jinx myself).

Buckwild27 · February 24, 2024

On 2/20/2024 at 5:14 PM, aapstealth said:

Hey Everybody long time lurker 1st time posting. I currently have a 2015 5.3 Ecotec with an On3 turbo Set up. The truck is doing well but I wanted to get a motor on a stand to start building. Scored a great deal on what was supposed to be a 2018 L83 but it turned out to be a 2020 L84. I've done some research on my end but wanted to get reassurance from those with more knowledge.
When it comes to the Long blocks are these engines the same? I know the front accessories changed on the L84 but it seems I could bolt everything from my L83 onto the L84. They moved the dip stick and removed the vacuum pump. The heads seem to have the same part numbers, as do the HPFP, Injectors, intake manifold etc.
I did see the L84 has a different DOD delete kit and I have heard mixed reviews on if a l83 DOD deleted cam IE Texas speed stage 1 or GDP Cam would work on an L84. If the long blocks are the same I am not sure why one would have a different camshaft.
For the build I am not going crazy simply doing a DOD delete stage 1 cam with a 10-20% Fuel lobe increase and possibly a bottom end refresh pending what I find on the tear down.
Also some information on my current set up if needed. On3 Turbo set up with upgraded 76mm Oil less comp turbo, currently on 6psi 93 pump making 550whp. Built 900hp capable 6l80e with Billet Stock speed stall convertor. I am content with the power and dont have any intention of pushing more boost if the stage 1 cam adds some power great but overall 550-600whp is plenty for me. From the research I've done it seems the stock bottom end can handle the power (Hopefully I don't jinx myself).

The only major change between the two is the DOD. but if you're deleting it then all should be good. The l84 is just the updated version of the l83.

CamGTP · February 24, 2024

The block is totally different because of the DFM, the L84 is a DFM engine and not a AFM engine like the L82.

So if the DFM delete kit is available, I would assume you need to use that over the standard AFM kit.

Edited February 24, 2024 by CamGTP

newdude · February 24, 2024

The entire valley is different on the L84.

L83 uses a VLOM in the valley plate, and has 8 oil passage bosses to feed to the VLOM.

L84 (and L82) obviously the front accessories are changed (especially water pump) but the valley is different. Each cylinder (4 for AFM or all 8 for DFM) have individual oil control solenoids and each has its own oil passages. Green is the harness to power the solenoids, the red paint lines are on each of the solenoids.