Engine conversion and bulkhead cutting ????

[smallfry]

I have just got back into LR ownership after a break of fifteen years, so I am rather out of touch with what is the norm nowadays. Bought an old 2.5 Turbo with a stuffed engine so something needs to be done..................

When I disposed of all my stuff last time round (and there was a lot) I kept back a 20k mile 3.5 EFI V8 for a rainy day, but with the cost of fuel nowadays, it seems to be almost a non starter. I had 18 various Land Rovers over the years, but most of them ended up converted to V8, so I know just about all the possibilites in that direction.

One of my questions is............ Is a V8 powered vehicle now considered "undesirable", hard to sell maybe, of much lower value if I were to sell it ?

Moving on, I have been looking at 200 or 300 TDI swaps. I fancy the TD5 or later stuff, purely because of the electronics. (dont like what they have done with the interior now either, but thats only MY opinion)

The 200 was always my favourite, purely bacause it felt more "proper", and back then did not seem to suffer from various unreliability problems that the 300 seemed to suffer (water pumps, overheating, cylinder head, brake pump, timing belt) most of which have probably been sorted by now I guess. So I want to stick with what I am familiar with and go with a 200.

Just as an aside, I cant believe how relatively cheap these engines are now, just as an illustration, the last time I bought a 200 TDI complete engine, it cost nearly £2000 ! They had not been out that long, and the 300 was only a rumour ! Not got that sort of money now anyway. Sadly.

Anyway, looking how conversions have been done, I am a bit puzzled, and I hope some of you can throw some light on what is considerered "acceptable" these days................

I am well aware that the easiest route is to buy a Defender spec engine with the high mount turbo, but I will discount that option as they are not easy to find and seem to be somewhat expensive, so i would be looking at a Discovery unit instead.

Now, to mount this in the seemingly "usual" position (4cyl petrol 2.5 NA and TD and 200) involves a rather sh!te downpipe conversion which also prevents access to the starter motor, and puts the exhaust rather too close to the clutch slave cylinder, which I personally dont think is really very satisfactory.

A chunk COULD be cut out the the footwell, to relieve the exhaust contortion somewhat, and maybe utilise the standard Discovery cast turbo pipe, although I think there will still be a problem with the clutch slave cylinder, but there seems to be some aversion to cutting the bulkhead ? Its not really much of a problem so why is this ?

But to me, the OBVIOUS was to go, is to weld new engine mounts on the chassis, use the Discovery gearbox and bellhousing (I know the gear levers and selectors have to be swapped) and shift the engine forward in to the position it would be in the Discovery or RR Classic (and the 300 Defender) This would then enable you to mix and match all standard parts, and avoid the problems of overheated bulkheads starters and slave cylinders....................

So what I want to know is, is there a compelling reason why this NOT normally done ? Something glaringly obvious that I have missed maybe ? After all, this is exactly what Land Rover did with the 300TDI Defenders.

On the other hand, there always the V8........................................

[Tetsu0san]

I can't offer any advice but this is exactly the conversion that I am planning on doing to mine with either an LT77 or an R380 and a 200Tdi from a Discovery, or possibly the same engine with a Defender R380. Changing the linkage if I use the Discovery gearboxes is the key for me as I don't want to cut the seatbox and lose the cubby box and I too don't want to mess about with an S shaped downpipe if I use the existing gearbox. It seems that having the 200Tdi further forward will help with pipework, access etc.

Someone said that if you use a Discovery R380 with the Discovery cross member it will move the transfer box about 2" forward so you will need different props, but the LT77 route negate this. I have an LT77 and an R380 from a Discovery, and an R380 from a Defender and various cross members available so I will be doing some measuring later today.

From what I can see in my engine bay I think that maybe the upright airbox in the front N/S corner might be an issue, depending on how far forward the engine is, but until I get that far I just don't know.

[Aragorn]

The 300 defender, and disco, has the transfer box situated about 2" further forwards than the older 2.5NA position, as well as the longer bellhousing.

If you want to maximise compatibiltiy with 300tdi/disco parts, then you'll have to replicate this.

Using a defender 300tdi crossmemer for the transmission will put the transferbox and gearbox in the right place, but you will obviously need the 300tdi defender propshafts to match.

You could retain the existing transmission mountings and propshafts, but use the longer gearbox, this will gain you MOST of the additional space that the disco/300 defender position gains you, but will possibly mean that various pipework wont reach or will need adjusted due to the engine sitting slightly further back.

I think the main reasons its not done, are the requirement to weld parts on the chassis (many people will happily bolt in an engine but cant weld or dont have the kit to weld) and the issue of the disco box gearstick meaning folk just stick with the short defender box.

Tetsu0san: the Disco LT77 and R380 are overall the same length and are essentially interchangeable. The transfer box on the disco was never moved, and was always in the more forward position. They moved the defender TXB forwards to match the disco when they went 300tdi.

[ejparrott]

I don't know about defenders, but in Series vehicles, 109's especially, fitting the 300 turbo and maniflold helps - it points the exhaust straight down, away from the clutch

[Tanuki]

The downside of the 200 is that some components are getting harder to source, meaning running such a vehicle as a daily-driver is not so easy.

Must admit, I've never been an enthusiast for the Rover V8, whether in original carbed 3.5 form or the later derivatives. I wonder if anyone's ever managed to mate the nice little GM 3.2 litre petrol V6 (from the Opel/Vauxhall Omega) to a LR transmission? That would be rather fun!

[=jon=]

I wonder if anyone's ever managed to mate the nice little GM 3.2 litre petrol V6 (from the Opel/Vauxhall Omega) to a LR transmission? That would be rather fun!

Do you know if the petrol Omega's used the same gearbox as the 2.5 diesels? IIRC they had a derivative of the BMW 6cyl diseasel in it, which was also fitted to RR's and some SA defenders... May be a source for conversion parts...

[CwazyWabbit]

I believe Forkrentfitter on here has fitted the discovery 200TDI engine in the 300TDI position when doing a number of conversions. Hopefully he'll see this thread and be able to throw the wisdom of his experience into the discussion.

[Tanuki]

Do you know if the petrol Omega's used the same gearbox as the 2.5 diesels? IIRC they had a derivative of the BMW 6cyl diseasel in it, which was also fitted to RR's and some SA defenders... May be a source for conversion parts...

That was the logic behind my line of reasoning! Not heard of anyone doing it though.

[bluehaze]

If you buy a new chassis ask for a 300 model and bolt the 200 motor in.

[smallfry]

Do you know if the petrol Omega's used the same gearbox as the 2.5 diesels? IIRC they had a derivative of the BMW 6cyl diseasel in it, which was also fitted to RR's and some SA defenders... May be a source for conversion parts...

In a word NO. The petrol AND 2.5 diesel Omegas used a completely different gearbox. Might have been Getrag ? It was an aluminium box, and I am pretty sure they had an integral bellhousing. Either way, the petrol bolt pattern is way different to any land Rover.

I had a 2.5 Omega engine and box in a Triumph Herald.........................

[smallfry]

If you buy a new chassis ask for a 300 model and bolt the 200 motor in.

Unfortunately the mounts are not in the same place.................................

[smokey_joe]

I have fitted 200tdi discovery engine and gearbox into a td 90. Personaly I like the fit.

Use the defender gearbox mounts and handbrake mechanism.

Cut off engine mounts and weld discovery mounts to chassis further forward.

Engine sits nicely in the middle of the engine bay,

Use standard disco cast downpipe. Just need to cut the standard disco first exhaust section and join to a defender one to give the step over the defender gearbox mounts, then use standard rear tdi system.

Use disco oil cooler pipes, coolant hoses, header tank, power steering pipes and intercooler pipes without modification.

Mechanical fan will not fit so you need an electric replacement.

To fit the disco radiator and intercooler frame you either need to lower the mounting plinths on the chassis or cut the plinths off the bottom of the frame and put the pins directly through as per a defender one.

The downside of the conversion is the gearstick ends up coming through the front of the seat box the other side of the high low lever, so you would loose a cubby box or middle seat.

It gives very good access for working on the motor. The belhousing bolts are easily accessible from under the bonnet so the gearbox can be dropped without disturbing the floor.

Definitely a good conversion that has been running for 5 years with no issues.

[daveturnbull]

My hybrid (sadly now deceased, bloody kamikaze spanish wench) had the 200 Disco engine and box in the disco position. I thought it worked quite well, but if I was doing it again I would get some heat on the gear stick and take the dogleg out of it to bring it forward a smidge. It does leave a nice amount of room around the engine for working on various bits.

I guess the reason most people opt for the TD position is because you can get away without having to weld anything, or cut the tunnel about.