Thread: rrc engine conversions, what are my best options?

I was going to say a Tdi300 but with that size of tyres forget it.
Isuzu 3.9 will be next option I guess.

Nothing beats a 4.6 high comp Rover V8 for ease of drop in. Other engines will cost bonkers amount of time money and effort to make run well. And anything bigger than a 4.6 and you'll start to munch the driveline. No V8 conversion will gain much in economy, it's the compression ratio and the camshaft that does that. Therefore possibly a turbo diesel conversion, eg the 3.9 Isuzu mentioned by Chucaro. And that'll need a robust manual gearbox at least.

I thin Marks do an LS conversion to the 4HP22 bellhousing but it involves a special starter motor and small flywheel.
You could use an LSX motor but you would have to fit a stout Modified 4HP24EH electronic to handle the torque.

So you would also need an aftermarket transmission controller.

I added up the costs at one stage for LSX,starter, flywheel , adapter, rebuilt 4HP24EH , transmission controller, wiring to run LSX, and gulped.

Oh I forgot rear sump and pickup from USA Camaro I think, and engine mounts etc etc.

Driveshafts have to be altered as 4HP24EH is longer than 4HP22.

A BIG job but you would have a honey at the end, even if it did owe you 20K.
Regards Philip A

Or just buy a D3 v8.

In my experience changing something in a Land Rover always has a knock on effect. At least the 4.6 is a Land Rover motor, although from a different model, might reduce complications.

304 injected holden , 4hp22 auto .
Beautiful to drive .

The following is just a personal view and I'm not trying to dissuade you, just providing some recent insights.

I suggest that you have a look in the modified zone on the forum. I posted a thread there a while ago on two specific engine swaps which subsequently got hijacked by the pushrod lovers. I know they mean well, but that thread was specific to 2 engines.

I've costed out several different engine options. the BEST option is for a turbo-diesel. It is certainly not the cheapest option by any stretch of the imagination. an LS seies v8 is easily done with off-the shelf bits, but at a price.

You have to make a decision at the outset. Are you keeping the RRC transmission and transfer case, or are you changing that out too? because it is all very much relevant when choosing engines. It also means additional costs and complications.

staying with the existing v8 you have top end options, stroker options and in-between options which require no downstream mandatory changes (until something breaks).

If you want to turn 37" tyres, diesel is probably a better road-going option. I'd pick a cheap and cheerful off-the-shelf v8 conversion for big wheels in short course work and to hell with fuel consumption. But then again, it would be more like a racing truck with 37's.
I'm wondering why 37's though, when you say 'Touring'. for Touring, anything larger than 33" to my mind is just throwing good money away - so I'm not sure what the vehicles intended purpose really is. Can you elaborate on the touring thing a little more? perhaps I'm misunderstanding you.

If you are looking for every swamp/boghole/quicksand/deep creek crossing between Shipsterns bluff and faraway bay then I guess 35's would do on an RRC, but tell us a little bit more about your application - because one can make a lot of assumptions when little information is given.

but generally speaking - if you intend to / are going to remote areas in Australia, you need a diesel engine, because petrol is just not as widely available as it used to be (chroming issue in indigenous population is touted to be the reason, but I call bull**** on that). It's not economical to cross the simpson or the strezlecki on a petrol 4x4 anymore. it will cost more than double what a diesel of the same displacement will. just ask a GQ owner.

Otherwise, if fuel is not your concern you can choose any number of engines, so long as they physically fit, and you can match them up to an appropriate transmission and transfer case. Inline 5,6 v6 or v8 - nearly all will fit - some just need a little persuasion. Common conversions are TD5 ot TDV6's OM617a, LS series and holden / leyland v8's.

One thing I would suggest you keep in mind is the mass of the existing engine. It's alloy block lends itself to naturally being quite a good choice, compared with iron block engines. keep that in mind as well as the location of the mass, as it has a very noticeable effect on vehicular dynamics.

After that, you will want to think about / need to upgrade your diff centres, Axles, hubs and CV's to meet the abuse a 33+ size tyre and large torquey engine will provide. A ratio change is a must to run 35-37" tyres. and possibly a set of crawler gears in the transfer case (depending on what transfer case you're going to run).

Then you'll want to think about brakes - in fact, if you're going bigger on tyres, brakes should be your first thought. Even the vented fronts imo are ****weak when it comes to stopping an rrc. Sure, you can get the wheels to lock up, but it takes some pedal, and if you have grippy tyres, it takes a bit longer than you think before the grip level diminishes to the point where the tyres skid.
There is simply not enough retardation with 'average' pedal effort. If you jump on them, the front will nose-plough the bitumen (it feels like it will) and then like any emergency situation in a non-abs vehicle, you will have to do all the modulating yourself to avoid the skid. Which is perfectly adequate, if you were raised on normal brakes and not nanny-state abs equipped vehicles.

You will need a body lift, a guard chop, flare kit and at least a 2" suspension relocation ( lift kit or drop existing mounts) and with 37" tyres, you will want the absolute best dampers money can buy to control the huge increase in unsprung mass. twin damper mounts front and rear and some custom made possibly some inverted tube 45mm dampers and thats maybe another 5 grand down the hole.
The other option is portals on the axles. This will allow the 37's to fit, but you'll still need to chop and drop. and it's still going to cost 20 grand.

Come to think of it... You should have a look at LRA's storm series. Pricing guide is not too far from reality. Think about it this way... their price includes labour. hundreds of hours of labour. If you're DIY'ing then it will still cost you, unless you can get everything you need for next to no money and you have plenty of time and skills.

You'll notice they don't need to run 35 or 37" tyres. It's not a 70 or 80 series tojo.

There are a tremendous number of threads on here pertaining to suspension and larger diameter tyres. I think all of them are worth a read. There are quite a few more detailed threads, but they will help you to gain a little more intimate knowledge of why generally speaking, a land rover does not need huge 37" tyres or 5" lifts to get offroad. For informational purposes and understanding, I'd suggest reading them, then decide if you can afford the big wheels, or portals or all the other sundry bits required to go big-rig on your RRC.

By this same token, I have restored several Mercedes-Benz and I can tell you that they are cheaper to own, maintain and drive than modifying a Land rover. You might think that is a funny thing to say... Don't laugh, because I'm not joking. So you can appreciate the fact that I understand what it means to throw good money after bad at something that only rewards you- once the funds are past the 'well and truly exhausted'. If you have a significant other or children, I'd suggest not embarking on the project, unless they are extremely forgiving and self-supporting income-wise. Seen too many mates make this mistake, so it's only fair warning on a project involving an engine swap and big wheels.

The cynical part of me suggests that you have a look at your bank balance before you start your project. if it doesn't have 6 figures to the left of the decimal point then you're going to be in debt before you finish the project. If it sounds like I'm being a wet blanket, it's because I've been there before.

I am always enthusiastic about a well-planned and executed project. I think if you work out exactly what the intended purpose is for the RRC, then you will likely change a few key outcomes, and the budget requirements to complete the project will shrink fairly dramatically.

For example, forget 37" tyres. That's going to save you nearly ten grand for a start. A set of 33's and a set of fibreglass flares and a 2" lift will see you done for almost anything. And engine swaps can be a nightmare, so investigate all the factory powered options as a start - isuzu, or the ford TD engines, as well as later v8's if you're not scared of ecu's. Many of these can be obtained from a donor vehicle which can be cheaper than simply purchasing an engine outright.

But there is always a mechanical sympathy issue, and big wheels basically = big $$$$ upgrades to the front and rear axles if you're gong to give this thing a big wellie after you drop a torque monster into the engine bay.

If you haven't checked them out, RPI Engineering do a stage 3 top end for the rover v8, and it's pretty good value for $. Or you could get it done locally if you know someone who has access to a superflow. That pretty much negates the need to do a swap out, and you can keep everything else pretty much standard until you complete the drivetrain upgrades (hitough half-shafts / ashcroft cv's lockers or atb's etc) and do an ATB upgrade on the LT230. Then do the wheels, lift & chop as desired, then drop in an alternative engine...

food for thought.

cheers for the wealthy responses.


this is the only picture i've got of the rig at the moment to give you an idea.


with a little bit of research and reading your responses staying rover is definitely the best option without going into the 5 digit figures,staying on the cheap side would be better considering i've got my bimmers already sending me broke and probably eventually single.


what is involved in the 4.6 conversion exactly? if there's any threads already outlining this i'd love to read it.

also in regards to why 37" tyres,I'm pretty much cruising around with 315/75/r16 m/t's at the moment and i just wanted something bigger as i'm just about to slap a 2" body lift all round on the rig,there's no real need for it,but I figured if i'm going to spoil the car I may as well have a cheeky little upgrade for the wheels/tyres as well.
But if there is no need for it i'm more then happy to keep rolling around with the 315/75's,which is practically a 35" tyre.

The 4.6 is a bolt in fit as a short motor with the 3.9 inlet manifold, camshaft, front timing cover and pulleys, crank pulley spacer, oil pickup and sump, and a couple of dowels need a bit of attention, one in the front of the block and one in the crankshaft flywheel face. All dead easy. Oh and ARP head studs. What IS important with a 4.6 though is to fully rebuild it with new stepped ("top hat") liners to prevent them coming loose in the block. You could import a complete short motor from the UK if you can't get a good one in Oz.