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Hi all

Posted something a while back about thinking about putting a v8 in my 1984 90 200tdi.

Loads of people said go for the 4.6 out of the range but after a bit of fishing round lots of people say it won't fit and I'm not made of money so I don't like the sound of this

The 4.0 I've been told also won't fit but I know they are in the 50th anniversary ones? So I'm pretty confused

What my question is is will a 3.5 or a 3.9 fit onto my lt77 box or do I need a new box? And what about engine mounts will they fit the ones I currently have? And what else needs to be done other than hoisting the v8 in and wiring it all up?

Cheers

Tom

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All Rover V8s will fit, externally they are pretty much the same.

Some models will require you fit an external oil filter, some not, it really is a case of suck it and see.

It's likely you will need to change engine mounts, I don't think they are in the same position as the 200TDI.

Gearbox will not fit, you need a conversion ring/spigot bush or a V8 box (LT85/LT95 or R380 IIRC), or just use the auto that regularly gets strapped to the back of a V8 ;)

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If you can buy and fit a complete 3.9 HOTWIRE SYSTEM - ir everthing

This gives you (IMHO) one of the best rover V8s ever bought

Near square = revs well, 4.6 long stroke and doesn't

Few (er) overheating liner cooling issues

Crank driven oil pump

Cross bolted block

Tunable when you have more £s

I prefer a 3.9 Serp to a 4.6 any day

If you can't get / afford serp get 3.9 V belt

Just make sure either are complete, have all ancillaries, loom and plug ECU AFM dizzy leads etc etc

4 wires and it will run ..4.0 = no chance - far trickier and some ancillaries are ££££s

:)

Nige

Nige

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As for this "what RV8 is best" debate, have look at this.... http://www.mez.co.uk/TuningTheRoverV8-pt4.html Table half way down comparing engines.

If were talking about commonly available engines, ie nothing exotic, then id pick a well rebuilt 4.6. Its about torque more than all-out revs for a Defender id have thought....

Maybe its just me being biased... :lol:

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As for this "what RV8 is best" debate, have look at this.... http://www.mez.co.uk/TuningTheRoverV8-pt4.html Table half way down comparing engines.

If were talking about commonly available engines, ie nothing exotic, then id pick a well rebuilt 4.6. Its about torque more than all-out revs for a Defender id have thought....

The table is good, although worth noting that he's quoting HP numbers at high RPM which is more race-engine / road-car style than useful in a big heavy 4x4 - it's an elephant not a whippet.

I'd strongly agree it is all about torque, from idle to ~3k makes for lovely off-road driving, you can bimble along at tickover and when you need a bit more, a tickle of the foot does the trick with minimal drama. Mods like shortened trumpets make for more HP higher up but lose you low-down oomph.

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The table is good, although worth noting that he's quoting HP numbers at high RPM which is more race-engine / road-car style than useful in a big heavy 4x4 - it's an elephant not a whippet.

I'd strongly agree it is all about torque, from idle to ~3k makes for lovely off-road driving, you can bimble along at tickover and when you need a bit more, a tickle of the foot does the trick with minimal drama. Mods like shortened trumpets make for more HP higher up but lose you low-down oomph.

I have a 3.9 running on Strombergs and it acts exactly like this. Very strong down low with no flat spots anywhere. It was serpentine but I replaced the front end with the earlier type to keep the fan at the right height. I didn't use the fuel injection 'cos of complexity and not wanting to discuss modifications with Mr. Plod.

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I have had 19 land Rovers over the years, series and 90/110 and Defenders. Most of them I converted to V8 as I would always have a V8 over a Diesel any day..............

ANY Rover V8 will fit. All the bolt patterns for the mounts ahd gearbox are the same.

Apart from the obvious stuff like fuel and exhaust systems and wiring, depending on what you choose, you...........

CAN use your existing chassis mounts and gearbox if its any good, but you will need to use an expensive conversion kit to do this.

You will also need to cut the passenger footwell.

Therefore, I would recommend using a Range Rover or Discovery LT77/R380 gearbox and bellhousing, which is longer, and this will shunt the engine forward into the position it is mounted in RR/Disco/Defender V8 models. You will however, have to swap the gearbox remoteand selector shaft, as the gearlever is in a different position. Or you could use a V8 90/110 LT85 gearbox, which is stronger, but more rare and therefore more expensive.............usually, unless you are lucky.

You WILL need to weld new mounts onto the chassis, But thats it really. VERY VERY simple.

Everything else is just a cocktail of standard parts.

You could also use an Autobox, which again is all standard parts, but if it has a Borg Warner transfer box, you will also need it front propshaft, which is longer or shorter (cant remember which)

As for the engine itself.............

3.5 is the nicest running and far and away the most reliable

The bigger engines suffer from internal water leaks, and CAN end up costing a lot of money if you are unlucky, the 4.6 being the worst in this respect.

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Reading some of your other posts Tom my only comment is to make sure the rest of the vehicle is in decent mechanical shape before contemplating nailing in a V8.

I agree this is only in the pipeline at the moment waiting for the right deal to come along in no rush and slowly getting on top of the mechanical condition my my landy recently had new brake servo brake lines front calipers all bar one wheel bearings but got the bearing to go on just need time axle seal etc etc so getting there hopefully one day will stop giving me grief and I can crack on with this v8

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I have had 19 land Rovers over the years, series and 90/110 and Defenders. Most of them I converted to V8 as I would always have a V8 over a Diesel any day..............

ANY Rover V8 will fit. All the bolt patterns for the mounts ahd gearbox are the same.

Apart from the obvious stuff like fuel and exhaust systems and wiring, depending on what you choose, you...........

CAN use your existing chassis mounts and gearbox if its any good, but you will need to use an expensive conversion kit to do this.

You will also need to cut the passenger footwell.

Therefore, I would recommend using a Range Rover or Discovery LT77/R380 gearbox and bellhousing, which is longer, and this will shunt the engine forward into the position it is mounted in RR/Disco/Defender V8 models. You will however, have to swap the gearbox remoteand selector shaft, as the gearlever is in a different position. Or you could use a V8 90/110 LT85 gearbox, which is stronger, but more rare and therefore more expensive.............usually, unless you are lucky.

You WILL need to weld new mounts onto the chassis, But thats it really. VERY VERY simple.

Everything else is just a cocktail of standard parts.

You could also use an Autobox, which again is all standard parts, but if it has a Borg Warner transfer box, you will also need it front propshaft, which is longer or shorter (cant remember which)

As for the engine itself.............

3.5 is the nicest running and far and away the most reliable

The bigger engines suffer from internal water leaks, and CAN end up costing a lot of money if you are unlucky, the 4.6 being the worst in this respect.

Thanks for the reply I think ill keep an eye out for the 3.5 with the correct box (lt85 preferably) as it seems the most straight forward

Is this what you'd recommend?

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A 3.5 with the correct box, if it's original (a Defender-spec 3.5) is at the very bottom of the pile V8-wise. They are de-tuned and often restricted (although most people have pulled the restriction out by now), as per every other engine ever fitted to the Defender. It will also be on carbs and points. It will not be very efficient, even by V8 terms.

From memory, the Defender 3.5's made about 100-110bhp, the same lump in the Range Rover was ~135bhp, with fuel injection it was ~165bhp.

The common faults with the larger capacity blocks are overblown IMHO, and a lot of P38's had engines replaced because of supposed porous blocks or slipped liners (because "they all do that, Sir") when the fault was really with the cooling system (stuck stat, knackered radiator). That's not to say they aren't more prone to it, just that you should not rule them out as long as you look before you leap as they bring a lot more useful torque to the party, and the P38 era blocks were the first ones Rover lavished any great development effort on (thanks to BMW's chequebook) for 20 years. Even slipped liners are not the end of the world/wallet these days either, top-hat sleeving the block seems to have come down in price and is now within the budget of a comprehensive engine rebuild if you're prone to doing it nicely.

You can buy a complete 4.0 or 4.6 P38 for £500 or less these days, by the time you've parted it out and weighed in the remains that's a very cheap 200bhp lump with a lot less years and a lot less miles under its belt than an old 3.5.

v8_engine_comparison.png

Buying the Defender V8 gearbox is the cheap route to something that fits, although there seem to be various pros and cons with the older V8 boxes compared to the LT77 or R380 which seem better supported. Depends on your aims & budget really - even a bog standard 3.5 on carbs is still great fun in a landy, but it's not the most fun you could be having ^_^

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Will a 4.0 fit in? I'm getting told it will not fit I also want it on a manual ideally so if I was to pick up a 4.0 lump with the bits and bobs I needed then keep and eye out for lt85 box would these then go together out of the car and then all I would have to so is hoist it in and mount it. Once that is done what sort or wiring is needed or what is next I really am a novice with engine conversions and this will be my first

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