What to do? Engine

I have a poorly old 2.25 which burns and loses oil from everywhere, i have long wanted to do an engine conversion and have been keeping my eye out for a v8 for spares. then the other day my mate said he was getting rid of his old jag (4.0 streight 6 auto) and if i wanted it I could have it. The hamster powered cogs in my head started spinning, measured up and i'm pretty sure i can get the motor in (if i move the grill forward and put a defender style one on it), i'm just not too sure what to do about a gearbox and transmission.

Would shoehorning a range-rover manual box onto it work? also will i need to uprate the diffs/half shafts?

is it worth doing or is it more like manufacturing a completely new transmission under her.

well first thing is gonna be yor insurance but we wont worry about that!
I fitted a BMW M5 straight 6 in my 90 using a disco v8 box as the bellhousing is bigger than the bmw one allowing me to make a simple conversion plate using 5mm steel. i couldnt have gone any thicker as the primaty shaft on the gearbox would have been too short to reach the clutch plate and spigot bush.
basically i got a ring if steel cut that was a tight fit round the flywheel, and no bigger than the bellhousing, drilled the holes to fit the engine, has a boss made to fit the end of the crank to house a v8 spigot bush. Then offered the gearbox up to the engine and drilled holes for that. It works perfectly although not the precice method of doing it as i may not have had the gearbox perfectly central to the crank, but its good.
I have made many conversion plates for things in the past and you just need to sit down with some measurements and work out what to do.
On the other hand an lt77 used to be a jaguar box so wonder if it could be done that way by finding a jag bellhousing.
If you use anything other than your series box you will have to change to coil sprung axles with cv joints, as your uj's in series front axles wont take full time 4 wheel drive. alternatively you could buy a kit from ashcroft which makes a later transfer box like a series one with 2wd. dont know how much they are though.
i could go on and on but i'm hungry!
if you have any questions please ask. Would be a very interesting series if you do it. I get a lot of interest in mine too.
Tig

You could get around the problem with using a permanent 4wd gearbox with the standard front axle, by fitting freewheel hubs and keeping the central difflock engaged - to engage 4x4 just engage the hubs. It would make an interesting conversion. Nice engine - twin overhead cam I think. I think it's got a cast iron block so it's probably quite heavy. A Rover V8 would be less high tech but it'll sound nicer, weigh less, and there's lots of info about doing the conversion because so many people have done it. I bet V8 spares are cheaper. I'd try to go for a Salisbury rear axle on it if you go for selectable 4wd, but you might end up with a very short rear propshaft

Thanks for the replies, been nosing around the jag today and it does look like its a good possibility that it will work.

I already have frewheling hubs but won't having the half shafts spinning constantly and not driving anything bugger them up pretty quickly?

And yeah i thought about trying to see if a jag bel housing would work with a Range/Land rover box as a lot of british transmission parts seem interchangeable with a little work. and i'm pretty sure the series box wont take that kind of abuse, they seem a bit on the delicate side as it is.

i'm going to try to get some measurements from the jag motor (don't want to start stripping it yet though as its still complete and movable).

A series will teke a v8 no problem but used harshly it probably wouldnt last.
As for a jag angine i think on the road you would go through a lot of rear shafts!
I used to break them regularly with my tuned up Prima!
With a later transfer box conversion and coil axles however there would be no problem at all as mine are still holding out with 300bhp and 260lbs of torque through them.
I do doubt whether a series box would last very long at all!

Tig9619 said:

A series will teke a v8 no problem but used harshly it probably wouldnt last.
As for a jag angine i think on the road you would go through a lot of rear shafts!
I used to break them regularly with my tuned up Prima!
With a later transfer box conversion and coil axles however there would be no problem at all as mine are still holding out with 300bhp and 260lbs of torque through them.
I do doubt whether a series box would last very long at all!

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Thanks Tig, i think that's the way forward then. Sorry for all the newbie questions.

I've broken rear half shafts on a Rover axle with a non turbo 2.5 diesel Transit engine, but the Salisbury axle should be fine (I've fitted one to a SWB IIA) - bigger half shafts, more splines and bigger diff. The thing to remember is that with permanent 4wd, the torque from the engine is divided equally between the front and rear axle, whereas using a series box in 2wd on the road 100% of the torque is going to the rear so it's much more likely to break. Some people say it is O.K. to use permanent 4WD with a series front axle (with Universal joints). I had to limp home once in front wheel drive once on my SIII and it worked quite well. There was only jerkiness going around tight corners, like pulling out from a junction - it was fine in a straight line.

Yeah I agree they are not too bad but for everyday driving I wouldnt think its much good, they just cant handle the speed of rotation with a perm 4x4 system.
I too have limped home in frond wheel drive, its an odd sensation. Like you say ok in a straight line but taking any corners at a bit of speed can be a bit iffy!
It perhaps would be worth a go for simplicity and see how it went but I'd swap to cv axles if going def/range transmission route i think.

It's a bit of a pain getting a coil sprung front axle to work with leaf springs according to a mate of mine. The track rod fouls the springs and you need to use military shackles with wedges between the springs and axle to make it work with a Disco 1 axle. I don't know anything about taking corners at speed in FWD or otherwise with an NA 2.5 diesel Sounds like an interesting conversion you've done ther Tig - nice to have something different

That was in my old series. i think i had to do it about 4 times. 3 halfshafts and a diff, or maybe 2! No they're not good in fwd only but when needs must!
Not something i would do on purpose you understand!!

and yes I do like things different!

oh and yes the axles can be a fiddle but i've seen them done quite successfully a number of times, you just have to spend a long time getting the axle central and the angle of the diff right. the rear is quite simple.
Tis a worthwile conversion i think if you drive one regularly and want to upgrade engine/transmission but keep the old series character!

Quite often, on items with both tags fitted, one is connected to ground within the equipment. check that out with a multimeter - else yu mite be supplying power to the grounded connection.

eh?

Tig9619 said:

eh?

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That was my reaction exactly

You might need to do a liitle more research on this - but it could just work:

The Jag 4.0 I think uses a ZF4HP22 auto gearbox (call me an anorak if you like)
So do most of the earlier Range Rovers, Discoveries etc.

You might find, instead of farting around with adaptor plates on the bellhousing, that you can keep the Jag engine and auto box together (and therefore keep the valving right in the 'box to suit the engine) ... then just get a transfer box off a suitable ZF4HP22-equipped Rangie/Disco and bolt it on the back.

It might not be quite that simple ... but worth checking out?

See BRITISH MAKES for other things that use the ZF4HP22 'box. It is very popular.

I think Stage 1 front axles have CV joints but they are rare.

Yes they do as they are used with the full time 4x4 box from a classic.
You are correct about the gearbox aswell. I have seen this done with a bmw engine in a racer. BMW in the 80's and 90's also usd the same ZF box and you can take the bellhousing off the bmw (and presumably the jag) box and put it straight onto the land rover auto box. Very simple.
I almost did this for my bmw m5 conversion but i really hate autos, and making a conversion plate for an lt77 was more fun!

If you want auto, I'd be tempted to try and keep the jag motor and box together, as I imagine the torque converter and valving will differ from box to box to suit the engine. If you can add the RR transfer box to the jag auto box you'd achieve this.

If you just swap bellhousings you're at the mercy of a potential mismatch between jag engine and RR autobox - although the dynamics of a RR V8 and a 4.0 Jag straight six probably aren't poles apart.

I'm building an auto Series at the moment, but heaven knows what it'll actually be like to drive!

You will have to keep the torque convertor with the engine as they may differ in bolt patterns so that will help. keeping the land rover box maybe better as the gearing could be more suited?!
Has to be tried to find out!

Don't know about that. Wouldn't the 1-2-3-4 gearing in all ZF4HP22 boxes not be the same, but final gearing down to the choice of diff or transfer box in the car? I really don't know.

Could be a cracking conversion. Must be room for a straight 6 in a series (even keeping a series front grille), Land Rover fitted one (the 2.6)!

Later ZF boxes (I think) had ECU's rather than being purely mechanical. If the Jag motor has an ECU (quite likely I'd imagine) the two ECU's might talk to each other, and you might need to keep that relationship.

I should probably add the disclaimer that I know absolutely nothing about auto boxes or ECU's!

Ha ha! Yeah the top spec bmw's in the 80's like mine had a switchable box with an ecu (which i just pulled out of my car for a manual conversion!). dont know about the jag boxes. p38 box maybe or thats all getting a bit complicated now!!