Thread: another S3 diesel transplant question defender into S3

There is a part time 4wd conversion for the Defender transfer case, Ashcroft, I believe in the uK, and that would be the simplest. The S3 gearbox and transfer case could be used (but you will need a four cylinder bell housing), but it is doubtful how long the gearbox would last. The diff ratio is a bit low for the Tdi engine, particularly with the Defender ratio on high range.

The front axle can be modified to fit CV joints, but it would involve significant one-off fabrication and machining. The simplest would be to fit front and rear axles from a Stage 1, which are designed for full time four wheel drive and would just bolt in, and are higher ratio. But they are not very common.

Off course, you can put coil spring axles in, but this means wider track, modifications to fit the track rod, wheel spats, and other problems.

John

thanks John,

Any thoughts on where the gear levers would poke up through the transmission tunnel? close to original or would they be all over the shop?

And when you say coil axles I assume you mean disco or defender ones

What about new diff centres for the army axles with the Ashcroft transfer case conversion? (this sounds pricey though).

cheers
Jim

On my S3 re-birth I decided upon a 200tdi with the original transmission and when I can afford it a Roverdrive overdrive. Driven without thrashing it, I think this will work, the gearbox being the part I have most concern for.
Advantages:
1. No changing of axles and finding hard-to-find axles.
2. No expensive gearbox mods.
3. No time-consuming axle and gearbox mods.
4. Fairly straightforward conversion.
5. An engine powerful enough to push a S3 in overdrive with advantages of a good cruising speed; hopefully less noise and better fuel economy.
6. Excellent fuel economy compared to the petrol engine.
7. Able to use waste vegie oil for fuel

Disadvantage:
1. $3000 + for the Roverdrive.
2. A few technical fitting difficulties for the 200tdi mainly related to the exhaust and turbo charger.

Originally Posted by chazza

On my S3 re-birth I decided upon a 200tdi with the original transmission and when I can afford it a Roverdrive overdrive. Driven without thrashing it, I think this will work, the gearbox being the part I have most concern for.
Advantages:
1. No changing of axles and finding hard-to-find axles.
2. No expensive gearbox mods.
3. No time-consuming axle and gearbox mods.
4. Fairly straightforward conversion.
5. An engine powerful enough to push a S3 in overdrive with advantages of a good cruising speed; hopefully less noise and better fuel economy.
6. Excellent fuel economy compared to the petrol engine.
7. Able to use waste vegie oil for fuel

Disadvantage:
1. $3000 + for the Roverdrive.
2. A few technical fitting difficulties for the 200tdi mainly related to the exhaust and turbo charger.

This is by far the easiest approach, although I would worry how the S3 gearbox will stand up to it - treat it gently, probably OK.

The original poster has an additional problem in that he is starting from a six - the bell housing doesn't match, and the engine mounts are in the wrong place. The Roverdrive should be OK with the 200Tdi, but I would not want to try a Fairey.

Jimmy,

Axles could be 90/110/Defender, Disco or RR Classic, but these do have problems as I mentioned. Chazza's suggestion of a Roverdrive plus the Ashcroft conversion on your LT230 T/C would work. I am not sure where the gear levers would be - depends on what you do about gearbox/engine location, and this is one of the factors you would look at when deciding on the position along with prop shaft lengths etc.

New diff centres would be cheaper than the Roverdrive I suspect - the front one in particular could be a second hand RR/Disco/Defender 3.54 Rover diff, rear 3.54 centres are available but not as many (and bigger job to fit as you have the Salisbury rear axle in the S3.

John

Link to those that have done it before -

Converting a Series Land Rover to a 200 tdi engine

Or you could do what I have just done. Use an Ashcroft kit to adapt the Defender 5 speed gearbox to the Series transfer case. This moves the engine 100mm forward. The engine mounts in a 6cyl are 76mm forward already? So you would need to make some new engine mount brackets to reach forward another 24mm. The Series transfer case has a lower ratio so is better suited to the 4.7 diffs and will give you around 3000 rpm at 100kph in 5th. With 4.1 diffs it would give you 2200rpm. (this is just an estimate, someone will come in with an exact figure to correct me I'm sure).

I'm doing this on a shorty and as yet have not fitted the motor / gearbox / transfer case to the chassis, but the way things are measuring up the transfer case mounts remain the same and the 5 speeds stick comes out of the same hole the Series box did.



By the way, the torque and power ratings for a 200tdi are almost identical to a Holden 186.

Defender 200TDI Power 80kW @ 3900 rpm Torque 255Nm @ 1800 rpm
Holden 186 Power 94kW @ 4200 rpm Torque 245Nm @ 1600 rpm
Holden 186S (2bbl. carb) Power 108kW @ 4600 rpm Torque 249Nm @ 2200 rpm

I think if you drive normally the Series box would be fine. When I eventually put a 200tdi in my S3 LWB Ex Army I'm going to bolt it straight up to the Series gearbox (after I change the bellhousing to a 4cyl).

Originally Posted by chazza

On my S3 re-birth I decided upon a 200tdi with the original transmission and when I can afford it a Roverdrive overdrive. Driven without thrashing it, I think this will work, the gearbox being the part I have most concern for.
Advantages:

1. No changing of axles and finding hard-to-find axles.
2. No expensive gearbox mods.
3. No time-consuming axle and gearbox mods.
4. Fairly straightforward conversion.
5. An engine powerful enough to push a S3 in overdrive with advantages of a good cruising speed; hopefully less noise and better fuel economy.
6. Excellent fuel economy compared to the petrol engine.
7. Able to use waste vegie oil for fuel

Disadvantage:
1. $3000 + for the Roverdrive.
2. A few technical fitting difficulties for the 200tdi mainly related to the exhaust and turbo charger.

Save yourself the money on the Roverdrive man and get a High Speed transfer case conversion kit. Mine's awesome! Cost less than $700 from the UK including freight.

Transplant the TDi with transmission straight into the S3. Then take a set of early Deefer axles, cut off the coil seats and weld on leaf spring seats (use square tube steel with a semi-circle cut for the axle tube profile, drill a hole to locate the leaf spring peg).
At the same time (oh sacrilege...) go Spring Over Axle with parabolics.

So, you get 3.54 diff ratios, an extra 4-6 inches clearance, highway cruising speed, low fuel consumption, no problems with axle strength.....


Jeez, I can't seem to find the negative aspects......