engine swap

[discodee]

Hi there When I got the rr the guy threw in a spare engine that he sais is in good nick and was running when he got it the cars fitted with a 3.5 V8 and the other engine is a 4.2 V8 off a newer model the original is an 87 and the spare is off a 92 I believe,does this cause any problems with the drive train with the increased power?and does it bolt straight on and what about the electrics etc has anyone done this before if so what problems if any did you encounter thanks for reading this,cheers the noo don

[Skibum346]

I don't know the answer to your question in detail, but I suspect with that age gap, you'd need to look at the ECu to make sure you have the right version... always assuming the 87 model does have one!

You may have drivetraini problemns if you use the extra oomph of the 4.2 all at once... but part of that will be a function of the age of the components. If it's the origonal gearbox and such... I'd have a are applying the fast button!

It's definitely possible to do though.

I know someone will be along in a mo to help further...

Good luck!

Skibum

[Guardian.]

i picked my 110 up yesterday, had a new 4lrt, replacing the 3.5, it lasted about 7 miles and ripped the rear prop to bits. how happy am i!

[discodee]

i picked my 110 up yesterday, had a new 4lrt, replacing the 3.5, it lasted about 7 miles and ripped the rear prop to bits. how happy am i!

mmmm that doesnt sound good sorry to hear that what are you gonna do!!!is there a stronger prop you can buy or are we talking stupid money for them or get them off the donor vehicle of the engine maybe Ill just punt the motor on to avoid the chance of doing any damage apart from what im gonna do offroad  :roll:

[Guardian.]

i think its just that props were shot anyway although seemed fine before the new one, just bad luck again i shuld think. new props fitted tomorrow so hopefully back on the road again!

[discodee]

Good luck and once you get on the road again can you please tell me how you get on if they hold up as id like a bigger engine you know what they say you cant substitute horsepower or some pish like that,cheers the noo

[Range Rover Blues]

I might suggest that the 4.2 would be better suited to an auto box but if you have one it will be fine.  The Borg-Warner T-Box and ZF 4-speed auto were used on the LSE 4.2 along with standard axles, props etc.

My LSE has a 5.0 TVR derived lump :twisted:  and the drivetrain is still standard LSE.  It has been for 10 years and only the rear diff has needed swapping.

As for the ECU you definitely need a 4.2 ECU or better still get the RPI Tornado chip upgrade, suitable for 5.2L or the John Eals ECU, again suitable for far bigger engines than yours.

The 4.2 was famous for running lean which can fry the engine, one reaosn you don't see too many secon hand/you see so many LSEs with 4.6 engines.

[discodee]

I might suggest that the 4.2 would be better suited to an auto box but if you have one it will be fine.  The Borg-Warner T-Box and ZF 4-speed auto were used on the LSE 4.2 along with standard axles, props etc.

the RR I have has an auto box in it im not sure what kind its the standard one how can I tell what it is is there a mark or number on the gearbox anywhere and any idea where I can get the ecus from that you mention in your reply thanks for your time, :D cheers

[Range Rover Blues]

Simple, how many gears does it have?

In truth the early (chrysler) 3 speed is reputedly stronger than the 4 speed ZF (which has lock-up in 4th) but I regulary tow 2 tonnes plus and mine is fine.

There's an ECU on flea aby at the moment, I've seen them go for £150  (like 3.9 ECUs used to) but I think it's up for less than £100
Otherwise the RPI website will have details of getting a remapped chip fitted to your ECU.

There is a number on the auto box but I'd expect if it were a 3.5/3.9 unit the only difference is that it might rev a bit more than the 4.2 box, otherwise it's the same thing IFAIK.

[Chris Kelsey]

It is common in Australia to put 5L chevs in the older RR without doing anything to the drive line and providing ur not dropping the clutch you shouldnt have a problem

[grizz]

If you decide your not going to put it in then drop me a pm an we might just be able to come to some arrangement about taking it off your hands