Disco Diesel Conversion

Maryland 110

Adventurer
I have seen 300 tdi's with OBD II ports. That engine harness is only about 90gbp for a defender. Most of these 300's that I have seen end up in NAS ie 93 and newer trucks. There is no economic argument that works in favor of a diesel engine swap in light trucks. The reality is you will probably never recoup your investment- especially if you use a truck valued @ less than $5000 as your recipient. The only reason these seem to make sense in defenders is that those seem to have a fairly stable value vs depreciation curve-not sure it makes sense even then, but its easier to justify to ones self.

thanks Frank
 
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David Harris

Expedition Leader
As far as weight goes, the 300 Tdi setup weighs 300 lbs more than the V8 you are removing so not a great deal of weight difference. In practice, not many "inspector" types as referred to above will think twice if the engine says Land Rover on top and the truck says Land Rover on the outside. Trust me, I deal with this daily and am intimately aware of epa and dot regs.

As far as importing an engine goes it boils down to what you put on the manifest. If you put 1995 Land Rover 300 Tdi Discovery diesel engine you might have an issue as this is a red flag. There are literally thousands of Tdi engines here and running the streets of America. While as Antisoshal says, they are "technically illegal", but so are tire size swaps as he so aptly pointed out. It boils down to this isn't a law that has been enforced- except in the widely publicised case of the Nissans. The only reason these engines aren't on the "legal" list is because Land Rover North America never asked/petitioned for them to be back then because they assumed we all wanted quiet smooth V8's due to our low fuel costs and the luxury icon they were pushing- obviously they were partially wrong. These engines in the UK had egr valves and cats so there is absolutely no reason they couldn't/wouldn't have been compliant here-LRNA just never asked. This has been an argument for about 1.5 decades now and those who have made the swaps are blissfully driving down the road and the nay sayers are still pointing their fingers. ECR openly documents gas-diesel swaps they do on their website-obviously EPA isn't knocking on their door or the work wouldn't be documented on their website. I'm actually in the middle of converting a diesel 110 over to a 4.2 Range Rover drive train for a client in California.
To each his own-its your money spend it as you choose.

This is a fair representation of why there are so many 300 Tdi's on the road in the U.S. It hasn't been enforced. I read on one forum, where a guy actually called the EPA and asked them about this and the rep replied that they are more concerned about companies importing the motors and swapping them as a business, than private owners converting their own vehicles. However, as the rep also said, since it is technically illegal, if you do ever come under the scrutiny of the law, local or federal, then you have no legs to stand on in court. Who's to say that the lax enforcement policy won't ever change? I can't see it getting any easier over time.
 

mongosd2

Adventurer
The problem is gonna be with OBD2 NAS vehicles with a non-type certified engine...You can argue all you about legality, this has been going on for a long time, it's not gonna stop, even if the fed's start enforcing the laws...

Doug, check out D-90 source, posted up the mods for the center console...
 

Viggen

Just here...
There is no economic argument that works in favor of a diesel engine swap in light trucks. The reality is you will probably never recoup your investment- especially if you use a truck valued @ less than $5000 as your recipient. The only reason these seem to make sense in defenders is that those seem to have a fairly stable value vs depreciation curve-not sure it makes sense even then, but its easier to justify to ones self.

Good point. A Defender, due to its rarity, is worth a swap because of their asking price and market value. A Discovery, as ubiquitous as they are, hust isnt worth the time or the money in the end. I am planning on keeping mine on the road for as long as possible but realize that we all lose the rust battle in the end. Have you ever noticed how little in the way of actual sheetmetal is available for these? I hope someone picks it up and starts to make patch panels for the common stuff. Ill be making a drivers floor patch this winter to weld in.

Pour $6000 into a $3000 Disco and youve got a $4000 Disco. Pour $6000 into a $10000 Defender and youve got a $20000 Defender.

Mongo, youre right. They cant catch them all and it will go on for a long time to come, especially in the rural areas of the country where they just dont care at all.
 

antisoshal

New member
The problem is gonna be with OBD2 NAS vehicles with a non-type certified engine...You can argue all you about legality, this has been going on for a long time, it's not gonna stop, even if the fed's start enforcing the laws...

I agree, which is why I modified my plans to a non-OBDII vehicle

I'd be very interested to see what "modern" V6 with variable displacement and such could be viably put in a D1 (or D2). Modern engines are implicitly tied to their computers and usually to their transmissions at LEAST. The ECU for a modern engine is usually tied in with almost every system on the car nowadays, and the amount of re-programming required to bypass/offset that will be righteous. In almost all cases, you'd have to use the engine and transmission as a pair, for starts. I looked into using the Mercedes OM647 engine, but the engine is highly integrated with the transmission through the ECU and you simply cant run them separated. The transmission is HUGE and I don't think it would fit in a D1, and used combos are pretty hard to find and expensive.

If you can demonstrate what "modern" V6 engine could provide a comparable power ratio and fuel economy that would even be moderately improved without a nightmare project, I'd be interested in the prospect.
 

R_Lefebvre

Expedition Leader
After coming to the understanding that... economically the diesel will never make sense. And now after driving my 5 speed V8 for a while, I'm finding I like the sound of the V8 too much to want a diesel anymore. :) I think I realized that what I really wanted the most about the TD5 was the 5 speed attached to it. ;)

Also, after driving my truck, towing the trailer and with a 17' canoe on the roof through the hills... I'm not sure I could bear to go any slower.

For me, the diesel lust is gone. I'll just buy more gascans. And try to take care of the V8. If it ever goes, maybe then I'll put a TD5 in instead of a new V8, but I'll actually hope that doesn't happen.
 

Antichrist

Expedition Leader
The economic sense of a diesel conversion really depends on your yearly mileage.
If you put a lot of mileage on you can recover your expenses within a few years, or less, depending on the comparative fuel costs in your area.
 

R_Lefebvre

Expedition Leader
I think it also depends on how you do it.

If you sell your V8, or if it blows up and you figure replacement cost on it anyways, then buy the engine and install it yourself, that's one thing. Writing a big check and picking up the keys when it's done... that'll be a lot harder to justify.

At least I'm sorta halfway there now since I already swapped the trans. I'd just have to change the input shaft and bellhousing to put a TD5 in. Of course, with a TD5 you're still going to have to monkey with the pedal box again because it's drive by wire.

Seems like a silly statement but... for me, I found the ancilliaries that you don't think about take about as much time as the main job. I spent as much time monkeying with the pedals, clutch lines and shifter as I did actually bolting the box in. I imagine the diesel would be the same. Fuel lines, throttle setup, wiring, etc will take as much time as the basic engine swap.
 

antisoshal

New member
If you sell your V8, or if it blows up and you figure replacement cost on it anyways, then buy the engine and install it yourself, that's one thing. Writing a big check and picking up the keys when it's done... that'll be a lot harder to justify.

Eh. I could build my own house too, but I prefer to have somewhere to live for the next few years that would take. I honestly don't trust my mechanical ability to the extent required to execute this. Based on my current schedule, it would be done right about the time they take away my drivers license for being unable to operate the vehicle safely. I enjoy the pride of maintaining my own vehicle when possible, but the scope of that type of job is honestly beyond me and I would likely waste as much money repairing my ineptitude and lack of knowledge as I would imagine I was saving. I want the vehicle to do things with, I don't simply want to build a vehicle.

In the end, I don't really justify it beyond the simple fact I want it, and I'm happy to pay someone who has spent the years required amassing the knowledge and skill to create it. They get money for their work, I actually get a finished product that undoubtedly works better than the monstrosity I would create, and I didn't vacuum away 2 years of my life in the process. Seems like a good trade. Money isn't worth anything if you don't use it being happy.
 

R_Lefebvre

Expedition Leader
I wasn't saying there was anything wrong with it. I'm just saying it makes the economics harder to justify.
 

Viggen

Just here...
The stuff that I was talking about is the Gen III Vortech V8s used in the GM trucks. Its work but it can be done and there is an adapter to allow the use of the LT230 behind a GM transmission. Swap it in with the transmission, motor and gas pedal (drive by wire) and youve all you need. It wont be easy but they do get great mileage for the power thats there. As for V6's, and V8 prior to the new Gen III V8s and the Vortech 4.3 V6, will bolt to the stock ZF auto transmission with a readily available adapter.

You would need to drive a LOT of miles in a few years to pay for the cost of the drivetrain, the cost of the install and the increased cost in fuel as diesel is more than midgrade per gallon. Here, its 3.06/ gal for diesel and 2.78/ gal for midgrade (what I run). Like I said, youre going to have to REALLY want a diesel to do the swap. I seriously was going to do it. Lined up a Disco swap "kit" and a shop to do it. Then, while driving my dads GMC around, started thinking about how a gasser would be easier and much cheaper and net me a few more mpg/ increased range, and the left over difference between a diesel and gas install will buy a lot of gas. Gas will always be cheaper than diesel. Sure, I could run waste veggie oil in it if it were diesel but I have no place to refine/ filter the oil and there is no place to buy it so thats not even an attractive option.
 

Maryland 110

Adventurer
You guys are getting mighty cerebral about this-rovers in general make little economic sense. I have already put 20k on my truck since I imported it in February. I'm getting over 400 miles to a tank-usually about 18.5 gallons. Nothing great but the truck has 242,000 miles and runs and drives like new. My rig has to be around 7000 lbs and its still a blast to drive. Not sure where the fast/slow thing is coming from. The tdi's, td5 and puma's/tdci that I have driven will hold their own with most disco's etc. I think if you drive one, you will prefer that experience to the V8's.
 
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piper109

Observer
I'm driving a 300tdi Disco in a state where there are no inspections.
I converted the truck because I wanted diesel and I wanted 5 speed. I just like to drive it that way.
Its a 99 SD and it was running fine on the V8 and ZF but I had a hankering and I did it because I could.
The economics of it dont make sense. I even paid a ticket to UK to yank and crate my engine/tranny plus the rest of the parts necessary.
It all works great with a/c and cruise from the V8. When I have sold the V8 engine, tranny, Y pipe etc it will have cost me about $2500 plus my labor, bringing my total investment to about 7k.
I have the satisfaction of being able to drive a diesel Disco so I can be smug.
A Defender might make more sense but my wife wont ride in the thing whereas she likes the Disco. When we move to the Blue Ridge she will drive it too.
I'm very happy with the way it drives. I dont find it slow as I have tweaked the pump per info on Dougs site.
Some people claim high mpg. I dont see how they get it. I still have to work on that. I get about 22 mpg US cruising at close to 80 with the a/c on full. Best I have got is 450 miles on a 20 1/2 gal tankful. I guess I will have to play with the pump a little more.

Steve
 

Maryland 110

Adventurer
Steve if you are @ 22 with a/c on running 80. Just me, but I wouldn't tweak a thing beyond that. Glad my website helped someone out.
Where in the Blue Ridge Mts are you moving ?
 

antisoshal

New member
Ya I'd be thrilled with 22mpg at 80mpg with the air on. I don't expect to do 80mph, maybe 70mph tops really. I'm more concerned about simply being able to hold speed at high altitudes and grades. I'm a pretty conservative driver so I should get pretty good economy crossing the great Nebraska wasteland.

I was looking at aftermarket water-air intercoolers to up the economy as well. I think the front end gets a bit crowded for airflow with the radiator, trans cooler, air conditioning condenser AND the intercooler, so using a water-air exchanger not only helps with efficiency, but I can maybe look at alternate placing of the radiator since I'm only routing water hose, not the actual intake air. You can get a decent short bore water exchanger and reduce the flow path, and longer water lines=better cooling anyway! This one claims only a .1psi drop in intake pressure.

http://www.frozenboost.com/product_...d=204&osCsid=2c6cb0ceaefd01efba2ff1a6e523a721

Maybe even a low profile hood scoop and a fan underneath, or perhaps inside the fender behind the wheel with a vent above pulling air down and through.
 

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