Hello,

I need help finding out how to LS swap my Discovery 2 without the use of the ACE conversion kit.

I have recently purchased a 2003 Land Rover Discovery 2. The chasis/interior of the car is in immaculate condition, the engine on the other hand has a slipped cylinder sleeve and needs a new oil pump. The engine has 166k miles and I think it is finally time to put an L33 into it. I had known about the ACE kit for a while now, but to my surprise they have stopped production/sale of their conversion kit indefinitely due to "rising costs and supply chain issues".

The ACE kit seemed to have the most support and documentation, and I also loved the idea of keeping my OEM transmission. I could not find any other company who sells a similar kit that maintains the OEM transmission and dash functionality. Instead I was able to find some kits that involve removing the transmission entirely and instead swapping in both the L33 motor and 6L80 trans using an adapter to connect to the transfer case. But they leave me with so many questions, primarily - How would you go about having the engines computer and the OEM computer interface with each other? I know that the benefit to this swap is that the transmission and engine will work together flawlessly, but how do I satisfy the Rover computer?

Is this something I could have someone like Summit racing program/wire for me? Any insight into how I can achieve this swap would be greatly appreciated. I am having serious trouble sifting through all this ACE conversation info - its all that comes up when you look for swaps.

I saw a great engine/trans at a junkyard today that would be perfect for this swap, but I do not want to pull the trigger until I figure out what route I am going to go.

Transfer Case Adapters:
https://www.marks4wd.com/mfp40200.html
https://rw-eng.com/collections/disco...oducts/adapter https://rw-eng.com/collections/disco...mounts-weld-in

Thanks,

 

There's a whole section of this forum dedicated to engine swaps. Posting your questions there is likely to get a lot more people who know about such things to look at them.

 

You don't need the Rover ECU to talk to the LS ECU/TCU to make it run. You'll run the LS 6l80 just like you would if you were installing it in an h3 or a supra or 64 Vette


You'd keep your rover ECU in place so hopefully all the major systems work.

What you may lose is your traction control. No worries there as if you can LS swap then you can install a CDL. If traction is really what you want you can also add selectable lockers or LSD diffs.


The 6l80 has very impressive gearing, you might want to regear to make the most of it. A disco was never really intended to run 90 down the highway so allowing max economy highway rpms to be around 80-85 could really makes 1st gear in low range impressive off road. I've not looked at the gear ratio calculator with the LS/6l80 combo with the disco.

You'll want to find a way to attach the Rover V8 temp and oil sensors to your LS motor. You'll want to find a way to make the disco tach read the LS output signal. If they don't speak the same language you'll need something like Dakota digital to make those signals interchange.


You'll likely have some warning lights you'll need to cover with black electrical tape. With a nanocom you can reset your disco to manual transmission to get some of them off. You'll lose your gear display but with some of the aftermarket console mount shifters you'll have an indicator light on the shifter. A horse shoe shifter would add some American muscle flair to the British rig.

You'll want to wire in your check engine light from the LS into the disco gauge cluster.

I'm sure I'm forgetting plenty but this is a start. It won't be seamless like the Ace kit but the 6l80 is a better performing transmission, maybe not more reliable in stock form but mo gears is mo better

I believe the speedometer on the disco runs off of the abs sensors so if the ECU is in place it should work although with tire size, trans swap and possible gear change it may be off. The LS ECU may also need a vss input for cruise control to work. The disco 2 with stock 3.54 gears and 285/70/16 tires is already way off.

I run the speedo on my vw TDI swapped 87 4 runner (using the 05 Passat gauge cluster) using a magnet pickup sensor that can be found all over eBay and Amazon. It reads the 4 bolts on my drive shaft flange. It is attached to a small box called a tach2vss. It is adjustable and allows me to dial in the speedometer to within 1-2mph. It's as accurate as my phones gps as I used that to set it. It takes the signal from the drive shaft sensor and converts to a signal the gauge cluster can read. Dakota digital also offers similar products, research needs to be done as to what voltage the disco gauge receives.

 

Hey thank you so much for this information,

Do you think I would have less trouble using a 4l60e and a GEN 2 5.3L LM4 or LM7? After doing some research I have heard some people having serious issues with the system on the Gen 3 engine that relates to selective cylinder fueling. Can this functionality be turned off with a tune?

 

On a heavy rig like the disco I would choose the 4l80e over the 4l60e, but the 4l60e can take some abuse and be built to handle all you can throw at her. The issue is the transmission pans on these transmissions. They are much much cheaper than the 6l80 but the pan makes a passenger side drop prop shaft near impossible to use. This is the case on Toyota land cruisers from the 40 to the 80 and pre 95 4runners/pickups as well as our rovers.


With a skinny enough front prop shaft, clock ring and enough lift it could fit but I'm not sure how functional it would be outside of a trail/buggy build. It would probably look ugly and make the transfer case sit stupid low. It would snag on anything off road like a big toe on living room furniture.

At that point you'd be better off ditching the land Rover axles and installing built dana 44s or some combination of centered rear axle, drivers drop front and an atlas or your favorite NP or Dana 300 transfer case. Then you could run the 4l60e with zero issues. I'm not sure how well wagoneer or k5 axles would fit under the Rover. I think I've seen some fj80 axle builds on the disco 2 but not much in the way of say 1 tons swaps that are so popular on jeeps.

Essentially if you do a LS/4l60e/one ton swap you could copy just about any jeep build other than getting your disco electronic items to function.


As for the asv for whatever GM calls that dumb running 4 or 6 cylinders on an 8 cylinder engine is, ditch it. Get the 700 some odd dollar kit and replace the cam/lifters/crap that fails and costs an arm and leg to repair. Any tuner can then reflash your ECU to run with all 8 cylinders all the time and not risk a poorly engineered attempt to get a better EPA grade leave chunks of metal littering your oil pan.


​​

 

A couple of comments:

You mention using an L33 with a 6L80. An L33 is a gen 3 LS engine designed for use with the Gen 3 electrical architecture. The 6L80 is designed for use with the Gen 4 electrical architecture. For this reason, an L33 will not operate with a 6L80 without an aftermarket controller, as the Gen 3 and Gen 4 architectures are not compatible. This combination (Gen 3 engine with Gen 4 transmission) not as good as a combination that was designed by GM to operate together out of the box (like a LC9 and a 6L80). I’d personally avoid using an aftermarket controller for the 6L80 if possible, and go for a combination that was designed to operate together by GM. The Gen 4 AFM and DOD can be deleted and is only present on certain engines.

The Gen 4 / 6L80 combo can be installed in a D2 and retain a similar level of integration. However, this is a substantially larger project than doing the Gen 3 engine and retaining the ZF 4HP22/24. A substantial amount things need to be moved around with the Gen 4 / 6L80. If people aren’t comfortable with welding / other fabrication, then they probably should not attempt this swap.

With the 6L80 or really any other transmission other than the factory ZF 4HP, the drivetrain is several inches longer than factory. So the mounts have to move around. Of the two main transmission adapters, the Marks 4x4 one is slightly shorter in length, which is better. However the Marks mounts puts the engine a bit too high in my opinion. The rear driveshaft will likely need to be shortened. The front driveshaft may need to be extended.

The 4L60 has major interference issues with the LT230 transfer case. No adapters for the 4L60 are commercially available that I know of for this reason.

The 4L80 is an option if you were to stay with Gen 3, but it is substantially longer than the factory drivetrain and the Gen 4/6L80 setup and the adapter is long to overcome interference issues with the transfer case. For this reason, it is not ideal, but can work with fabrication. The electronics are similar to the Gen 3 setup with the 4HP, but require additional dedicated components for translating gear position and VSS.

There are several ways to deal with the electrical side of the swap, and in my opinion, some ways are correct and others are not. If you want the same level of electrical integration as the ACE kit, then dedicated electronics / parts are necessary to interface with the Gen 4 electronics. These are not parts that can be purchased, but have to be built from components, so a person doing this swap would need to be comfortable with soldering breadboards and more than basic wiring. This is fundamentally why most of the Gen 4 / 6L80 swaps end up incomplete.

 

Thanks for the reply, super helpful.

Considering that the ACE kit is off the market for the foreseeable future, how would you go about completing this swap while retaining the factory ZF 4HP22? Mine was rebuilt just 20,000 miles ago by the previous owner, so If I could retain it that would be great.

The only bell housing adapter kit that I can find seems to be the marks 4wd kit. If I got an older model 5.3 LM7 or LM4, I would assume much of the electrical integration would be very similar to how ACE does it, I would just need to find someone willing to share their wiring instructions that were provided with the ACE kit so I could wire it up myself. I would also have to fabricate my own accessory brackets for the A/C compressor, alternator, and power steering pump.

 

I believe ace has a little black box that works as an interface converter to make all the LS stuff work with the disco ECU.


I think the issue with the marks 4x4 SBC adapter is the torque converter needed. If you can source that converter you're a 1/4 of the way there. The comes making the electrical mods.

 

There is a good FB group for this called USA Land Rover Discovery 2 LS Swap

Honestly, its an expensive and time-consuming swap and you needed to be a pretty good wrench even with the Ace kit.

I would just pull your current motor, find a 4.0 motor with good compression (hint-hint p38), and you could swap it in and be up and running much faster for much less $$$

 

I was of the understanding the D2 and LS will not work with Marks SBC to ZF 4HP adapter.

I am working on a summary of a DIY LS swap, but it is taking a while to complete.