Switching from 4.0 V8 to Diesel

[tedwardasu]

I've been browsing the site for information on costs, pros, and cons of switching to a diesel engine. I drive a 98 Disco with the 4.0 V8. Can anyone who has converted from gas to diesel reply about power loss/gain, mpg change, cost, compatability, and overall satisfaction? I'm obviously looking at the 200Tdi and 300Tdi... but also am very interested in the HS2.8L from www.disco-tech.com for $7500 with the fitting kit. Is this reasonable price? If so... can anyone clue me in on what the outrageous installation cost may be? I love my disco and don't want to give er up, but the 4.0 just isnt cuttin it.

Thanks!
-ted chestnut

 

[p m]

Ted, in which way is 4.0 not cutting it? Where are you located?

in the U.S., the only argument for swapping to diesel is to do the "right thing" for the environment. Swapping one 4-liter V8 (15mpg) for a diesel of comparable performance (22mpg) saves two people driving Toyota Camrys (30mpg) from having to buy Priuses (45mpg), for the same mileage travelled.

FWIW - at the price of premium gasoline of $2.75/gal and diesel of $2.50/gal, you'll be saving approximately 7 cents per mile travelled. The Powerstroke 2.8 conversion will pay for itself in about 100kmi.

 

[tedwardasu]

I live in the mountains of north carolina (Boone). I drive up very steep roads including highways (421 into Boone if you are familiar is brutal). With the petal to the floor, i can get er goin 45ish. It doesn't get cold enough during winter to pose a problem with the diesel i think - average lows of 25 or so in january. A big question is, would a diesel help on those long inclines? If so, I'd be compelled to convert simply because 90% of my driving is up and down. I also understand they are more reliable and less likely to cause problems which is huge for me because i travel all over for snowboarding. Also, I plan on selling my current engine with 78k miles. If anyone knows the price range these sell for It'd be much appreciated as well.

Thanks for the feedback!!
-ted chestnut

 

[Iron Boots]

Email jesse at the shop...he knows the detauls better than I do on Dave's truck....It is nopt cheap. I do know that.

Typically it's more involved than just an engine swap as teh Torque converter locks up and stalls at differnt times between gas and diesel. I know it took a lot of time to Square daves away because he kept the stock ZF torque converter etc.

pm me and I'll give you jesse's email. I don't want to post it here and annoy anyone.

RJ

 

[ShaunP]

The biggest problem with the 300 TDI engine is timing belt failure. Make sure the engine you use has had the factory retro fit kit fitted it will be fine. What happens is the belt gears are not lined up properly on some engines and the belt walks off and rubs on the timing case till it wears thin and breaks. The good thing is that the valves hit the pistons at exactly 90 deg so they don't bend or cause any piston damage, normally they just bend a couple of push rods and maybe break rocker. TDI cars also have a lower ratio high gear in the transfer case as well as different shift points and convertor lock up. Lotts of them are 5speeds here in Oz. You can tweak the Bosch injection pump and turbo waste gate for some extra grunt and less turbo lag. My dad has a 98 tdi Disco and once on boost it goes like a train and you can't cry about the 900km per tank of fuel. One of the mates has one with a 140 litre Long Ranger tank, does 1300km per tank on the highway I think.

 

[Rocky]

The timing belt issue was a brief screw up by Land Rover several years ago, remedied by a recall kit.
All Tdis and Powerstrokes are now made in Brazil, where the 2.8 is used in the Ranger pick up and tdi in South American Defenders, plus exports to South Africa and any vehicles built in the UK requiring tdi engines (only to military and remote areas with no emissions controls).
Expect to pay $10k plus fitting which is a HUGE expense, and don't forget the need to modify the gearbox for the TDI.
A bigger engine and/or gearing change is what you need
A 4.6 will give you 240bhp/300ftlbs and get parts for it from you favorite source unlike the diesel
Regear your diffs with either 3.8 or even 4.1.
Regear your transfer box from 1.2 to 1.4.
Sources include great basin rovers (USA) Ashcroft Transmissions (UK)

Each has its pluses and minuses, and of course $$$ associated with it.

I'd stick with the V8 and go with the re gearing as the first stop. Let us know what you decide

 

[LuisC]

I've also been contemplating the swap. But I'm thinking more along the lines of mothballing the diesel until my V8 goes south. Which, the way I take care of it, could be another 100K miles. Unless, of course, something lets go.
I keep hearing different stories on life expectancy of the V8. Anywhere from 175K to over 300K miles.
I just want to make sure I have a diesel to put in there when the time comes. Not that they are discontinuing the HS2.8 anytime soon. But they may eventually be more difficult and expensive to obtain later on.

 

[ShaunP]

Maxi Drive and Jack Mac in Australia also make diff and transfer gear sets. I'm figuring if you guys are getting new TDIs from SA you won't have the timing belt issue then? 300 tdi engine had the problem from 94 to 97 to a lesser or greater degree, Ive seen cars toast a belt in 5k. TDI 200s were fine however. There is a crowd in the Uk called Zeus who make a gear drive to replace the belt but it costs heaps, and I have come across 2 blokes here that have had them fail and wreck the crankshaft, belts($40 AUD) are cheap, change them before they are due. Nothing else seems to go wrong with them here except for the odd head gasket and lift pump. For $10k US you could buy a sweet Autralian TDI and convert it to left hook,or get a crashed OZ car for $1.5k and just do a powertrain swap on a US car. Shipping is not much, a mate of mine just took a MK2 Jag to the UK for $1.5k AUD from Brisbane.

 

[LuisC]

Shaun P,

I've often wondered about the gearing and probably more so, the torque converter when converting, because power range of the diesel is somewhat lower than that of V8s.
I looked, but couldn't find much in the way of regearing for diesels. Even Maxi-Drive and Jack McNamara info is limited on this. MD Engineering in th UK says no regearing is needed and even has an adaptor so that you can keep the same transmission from behind the V8.
Do you have any website info on this.

 

[Sirfoss]

300tdi

I have fitted the 300 TDI to D-90s/Rangies and Disco's and I think it is great as far as those hills you have to climb no prob even if you have a trailer attached. You can climb these hills and you actually wont see your mph go down. When done the kit includes all includeing a differemt transmission (recomend) Takes about 20 hrs because the relocation of eng mounts and elec harness that has to be fabricated. Email me or call and I can tell you all about it.
Mike

 

[ShaunP]

Guys I have mis led you, I just looked up the specs of Australian TDIs and the transfer case is the same ratio but the 5 speed has different ratios this is what I was thinking of. The auto shift points are different as is the convertor lock up however.
TDI auto specs

Lock up 46-49 mph 1600-1850 rpm
unlock 45-48 1700-1800
shift points light throttle
1-2 = 13-14 mph
2-3 = 21-23
3-4 = 24-28

Full throttle
1-2 = 26-29 3500-3800 rpm
2-3 = 46-51 3600-3900
3-4 = 64-76 3400-4000

Kick down

4-3 = 62-72
3-2 =43-49
2-1 =23-36

TDI cars once on boost (1500rpm) pull really well and will hold speed better than a v8 on a climb as the load makes them build boost. The factory TDI car have alot more sound proofingthan the V8 cars to try to keep them quiet as well. Australian TDis have heated windsreens as well because these engines run cool and they won't defog the glass quick enough to meet the Australian dot laws. They require a bit of getting use to as until they come on boost they are quite slow. A tweak of the pump brings them on quicker but makes them blow a puff of smoke. Standard boost is about 13-14 lb but they are sweet with 15+ and this causes no problem. The engines are heavier than a V8 and you do notice this over the front end if you are used to driving a V8. With good springs and shocks you won't notice this. Also if you drive them through water you need to fit a wading plug in the vent hole in the base of the timing cover so it doesn't fill up with mud and water and wreck the belt. They run a smaller rad and the alloy intercooler takes up the space be side the smaller rad. The late TDI cars are fly by wire here and have an ECU, I would recommend using they earlier version with no ECU makes them simple. Common faults in Australia are timing belt failure (this can be fixed by one of 3 retro fit kits depending on the engine) the odd head gasket, the pipes crack off the top of the lift pump and leak fuel and the auto cars sometimes crack and break the torque convertor drive flex plate. Also TDIs seem to wear out steering dampers quicker than V8 cars. In Australia TDI cars fetch a price premium on the second hand market of around $1500 over the same spec V8. They are pretty good thing really.

 

[LuisC]

Thought I might add this web page because I keep reading that I can't use the same transmission and the likes.
Here it is;
http://www.mdengineering.co.uk/faqs.php?p=faq
This seems to address some of the questions regarding mods that need to be made to a V8 Rover to fit a diesel.
MD seems to have a kit with all the adaptors and what not.

 

[ShaunP]

Luis the kits aren't cheap are they. You almost could buy a good TDI Disco in Australia for that type of money. A mate of mine brings in damaged low milage Discos from Japan, Murray strips them for parts I think he gets them for stuff all. I wonder if you could get a complete Jap Disco TDI to the US for the right money take what you need and sell the rest for parts. Some of the ones Murray has imported to Australia have had as little as 20k km on them.

 

[LuisC]

Sounds like I need to take a trip down under.
Been wanting to for a long time anyway, but I keep going back to Asia.
Seems like Asia is the only place in the world where us Yanks are welcome anymore.
And even that is a bit shaky.

 

[ShaunP]

You guys are ok here, we don't really have any drama, where a bit far for most to those sorts of peple to come and we are not as hated as you guys yet. Our biggest worry is from Indonesia and Jama islamia, thats the mob who blew up the bars in Bali and set off a bomb in front of our embassy over there. Stupid idots without Australian tourists going there they'd be broke, in fact I think they pretty much are now because no one goes anymore.

Tony at AJS spares was wrecking a 300TDI a few weeks back it had a hit up the back I think. If you could get on to something like that you could get all the bitts you need and it would probably work out ok with the exchange rate at 70c.

 

[dmarchand]

Typically it's more involved than just an engine swap as teh Torque converter locks up and stalls at differnt times between gas and diesel. I know it took a lot of time to Square daves away because he kept the stock ZF torque converter etc.

Thanks Shop Boy for the plug

We reused my '97 ZF (your ZF needs to be the hydraulic type, not a later model electronic), and 1:2 TC. The "time" taken to square away things was really spent on modifying the brackets sent to retorfit the 2.8 to the NAS V8 frame, and to adjust kickdown and throttle to get things right. Sounds trivial but they ate up time, plain and simple.

You can get away with reusing the v8 ZF but the shift patterns are a little chunky. But, knowing now, what I did not know at the time. You can buy the proper ZF governor $100-300 for the tdi and replace yours in your existing ZF. I may do this or may not. Same goes for the TC. I like the 1:2. I may switch to 1:4, but don't feel swapping a perfectly good TC is worth it. Mine is original with about 90K miles, so I assume it will give up the ghost in due time and I can choose to swap to the 1:4 and maybe swap the governor in the ZF then. But it's NOT necessary to get you on the road. You of course need to take in account gearing at the diff side too. I run 4:10 with 33" tires.

It's a big project, of course. But nothing magic to it. I think the trickiest piece is going to be sorting out the electronics in a DI.

In addition, while your assuming your only spend will be on the engine and/or kit. It won't be. Once your in it, you'll find your project list grow exponentially. You'll find yourself saying: "well, since I'm in here, I might as well do this...". You've been warned.

 

[96'RoVaTrUcK]

Yeah those hills he is talking about in boone suck bad. I snowboard in banner elk often and its right near boone and it feels like when you start up a hill it never ends. When the rover pedal is to the floor it feels like you are just creeping not fun at all. I was wondering does anyone make perfomance parts for the TDI. I dont think banks or edge or bully dog do. But i know you can really pull some power out of a turbo diesle.

 

[ShaunP]

What you can do to get more power first up is to tweak the fuel pump and waste gate(really easy), you need to be carefull not give it to much fuel or the exhuast temp goes up and you can toast the motor. Lotts of guys here that want more grunt also fit a bigger / another intercooler and a 3in exhaust. If you combine pump, wastegate adjustment exhaust and intercooler you get good power increase.

 

[LuisC]

ShaunP,

I had been to one of those bars in Kuta, Bali a year before. I would still consider going back the Bali, but I'm less likely to patronize establishments that cater to non-locals.
I'm one of the few Americans that backpacks all over. Sleep cheap, eat cheap, hitchhike, everything that Europeans and Australians are accustom to.
I have also notice a change in attitude towards us over seas, mainly in Europe and the ME, especially since Bush's Iraq thing. I was in the ME when the war started 20 months ago. Instantly, attitudes changed towards me. BinLaden t-shirts were selling like hotcakes.
Anyway, back to the subject on diesels. MD Engineering makes a performance kit for the 200 and 300. It does away with the waste-gate turbo and uses a variable geometry turbo. Has 22 lbs of boost at idle.

 

[ShaunP]

I reckon that would fix them. The only problem with them really is before they are on boost. Its not so bad with 5 speed because you can slip the clutch but with an auto you step on them and the engine makes some noise and you reckon you could walk faster, then after a few seconds woosh the revs come up and it's away. When they first imported the TDIs here they were mostly 5 speeds, the POMs could not understand why we would want autos and they took some convincing for a while. If you turn up the boost sense diapram in the top of the injection pump this brings them on boost much quicker as does a big exhaust. With 22 lbs of boost they'd fly. In standard trim they make about 14-15 under load at 2k or so. My concern would be how long would it last. Standard they seem to have no trouble getting over 200k miles with no major probs except for the timing belt problem and maybe a headgasket. My dad's 98 tdi has done 160k km (100k miles) and the engine is like new, it's only had normal servicing. The poms seem to not mind rebuilding engines, in Australia we expect to get at least 350 k km before we touch them which is why I'd be worried about trying to get too much grunt from one and toasting it. I guess in a place like England which is small if your car stops your not far from somewhere but in Australia if it stops some where in the outback you could be days from anywhere, best case is you have sat phone and it costs you $2k to get your car back to somewhere where you can fix it worst case is you don't make it back.
Anyway it cost you nothing to tweak the pump and waste gate and not much for an exhaust and this gives them a good increase in power without putting undue strain on the engine.