Hello I’ve been on this form for a little while, but not too long ago. I just purchased my first disco 2. I just want to know should I throw in my LM7 I purchased a while back or should I rebuild the 4.6. I bought the truck with a slipped cylinder liner, and I already knew that I would half to do some engine work, which I really don’t mind. It’s a project. I want to make a rescue rig/every day but I don’t know which avenue I want to take. I did some research on the ace kit which sounds very interesting but I don’t want to lose the authenticity of the truck but I know I won’t be able to get the horsepower. I want out of the 4.6 if I want to be a rescue rig on Overland expeditions. So I was just wondering what you guys thought also, how much would it cost to rebuild the 4.6. Thanks everyone!

 

To me, I'd swap to the LM7 10 days out of 10. There are folks that feel different, but at the end of the day I think it comes down to what you feel comfortable with and what you like. #LSTheWorld

 

I live in the interior of British Columbia with relatively steep and long mountain highways. I feel that the 4.6 in my P38 is adequate for this. My 4.0 in my Disco I feel is a bit less than adequate. The LR engines aren’t bad and are really pretty reliable as long as you don’t overheat them. If keeping it original is important, you should keep the 4.6. As said above, you need to decide which way is better for yourself.

 

How many miles on the engine? I would do inspections and compression, pressure and leakage checks before ripping the engine out. Liners can be pinned. Gaskets and seals can be replaced. If the main seal and cruciform do not leak, engine can stay in. Think about a new oil pump. Clean the hydraulic lifters. Clean the injectors and replace their o rings. And do the mods like PCV valve, coil relocation and inline thermostat. Think about adding an oil cooler (I added a stock cooler with sandwich adapter) and oil pressure gauge. Flush the cooling system, new radiator depending on mileage.

 

I like an LS as much as the next guy but for me they are just not worth the cost to upgrade. Everyone talks about the power differences, but most of that comes down to camshaft selection. If you look at HP and torque, the 4.6 only gives up 15-35 ft lbs of torque to the LM7 and most of that is RPM related. The 4.6 makes peak torque at 2650 rpm, not 4400. Was just off-roading this past weekend and most of my time was spent under 1500 rpm. Towing - again I am guessing you probably want most of your power below 4400 rpm, not above like an LS? Don't get me wrong, LS is great in my Camaro, but not ideal for truck duty. If you really want LM 7 power you could put a TVR or Morgan camshaft in the 4.6 although you would be giving up that valued low rpm torque curve. BTW, take a look at the rebuild kit cost between the two, LS is not as cheap as a Rover V8 to rebuild.

 

I’ve heard of pinning the cylinder liners and the truck has 126,000 miles on it . How much would it cost to pin the cylinder liners? Would that be a better avenue to take? Also I was going to send the LM7 off to a machine shop to get rebuilt. I was going for a torque build so I can tow some things around also it would be really fun to have that to work went over landing since I do want this to be a rescue rig. I know a guy who said he would swap the engine and do the wiring for me for 2000 and the engine rebuild that I want will be 1700 which honestly I think it’s a little high. If I get the ace kit, I was going to get the wiring harness that they include with it so I know for certain all of that will be 5 to 6000. What I’m really worried about is the exhaust though. I don’t know if I would need someone to make custom exhaust or maybe I can find a website to where I can buy a kit for it which I doubt they have.

 

We live in the country so we have problems with field mice and I just got the three amigos. I can see where the critters nibbled on some of the wires. But besides that there were no check engine lights or lights in general on the dash. reason why I thought about pulling the engine was because the oil leaks. even though the gaskets aren’t leaking. But under the truck you can see there is some substantial oil leaks going on.

 

At 126k I doubt there is much wrong with. I would start by doing the PCV mod at the top of the forums, an inline thermostat, clean the oil off the engine with some oven cleaner or purple power, and then start fixing things from there. Does not sound like it really needs an engine swap.

 

Well, yeah, there really isn’t much wrong with the engine. It’s just the slip cylinder liners. They’re sounding really really rough…like really rough.that’s really the only reason why I want to do the LM7 swap.

 

Pinning is a hack fix at best. The previous owner of my Disco pinned the block. After a few hundred miles of ownership, three of the pins fell out which caused a massive oil leak and the three liners started banging around. It made quite a racket! When I dropped the oil pan I saw that he'd gone too far and the pins fouled all of the piston skirts. The block wall is pretty thin so there is very little material for the threads of the pins to engage. I looked into the cost of tophatting the 4.6 and all the other things that needed done and the cost was pretty high. Swapping in an LS based engine in was cheaper. I went with the L33 which has a truck intake and makes nice low-end torque. The L33 is all-aluminum so only weighs a bit more than the 4.6L that came out. The specs on the 4.6 are 217 hp and 300 lb-ft of torque. The L33 makes 310hp and 335 lb-ft of torque. The additional 93 horsepower does make a difference.

I used the ACE kit. It's pretty good but the instructions can be a bit sparse in places. A few mods were required like grinding down a boss on the bell housing to prevent my driveshaft from contacting it as well as slotting the motor mounts because they didn't line up properly. I took my time since it wasn't my daily and I spent a little over a year on the swap. I'd say it's certainly worth looking into.