Thread: Engine Conversion LS or 4BD1T

Originally Posted by topender

Hi Everyone. First post! An interesting set of posts. I have a 96 RR 3.9l that guzzles fuel like there is no tomorrow (33l/100k - driving with eggs under the accelarator) and I made a few enquiries about swapping to an Isuzu but was told by some "in the know" that it was not really feasable - expensive and fiddley with lots of mods necessary. Was I being given the good oil? or are there some LR mechanics who are purists and see tampering with the original design as sacrilage? I live in Darwin and there doesn't appear to be many options when it comes to getting my problem solved. Any help or suggestions would be greatly appreciated. Thanks.

Are you towing a 22' full sized caravan with you .... That's close to my LPG consumption towing a full sized, full height caravan that the range rover looks like a matchbox toy infront of!

Unfortunately 'No!". This is the fuel consumption driving carefully - no rapid acceleration or gas-guzzling deeds.

Then there's something very wrong. No need to change the engine - just fix what you've got.

Originally Posted by topender

Hi Everyone. First post! An interesting set of posts. I have a 96 RR 3.9l that guzzles fuel like there is no tomorrow (33l/100k - driving with eggs under the accelarator) and I made a few enquiries about swapping to an Isuzu but was told by some "in the know" that it was not really feasable - expensive and fiddley with lots of mods necessary. Was I being given the good oil? or are there some LR mechanics who are purists and see tampering with the original design as sacrilage? I live in Darwin and there doesn't appear to be many options when it comes to getting my problem solved. Any help or suggestions would be greatly appreciated. Thanks.

SheldonA on here is putting a 4bd1 in his p38 rangie. Have a look in the p38 section

Originally Posted by topender

Unfortunately 'No!". This is the fuel consumption driving carefully - no rapid acceleration or gas-guzzling deeds.

Get a timing light, advance the timing at idle to 10 degrees BTDC and make sure your vacuum advance is working. Stock timing setting and a stuffed advance capsule will make your truck extra thirsty! There are a few other things that you can check after that to reduce fuel usage to a more normal level for a low tech V8.

Edit: and I just noticed that you have a non existent vehicle. It is either earlier than 1996 or it's a 4.0 or 4.6 litre which don't have a distributor to adjust.

Originally Posted by topender

Hi Everyone. First post! An interesting set of posts. I have a 96 RR 3.9l that guzzles fuel like there is no tomorrow (33l/100k - driving with eggs under the accelarator) and I made a few enquiries about swapping to an Isuzu but was told by some "in the know" that it was not really feasable - expensive and fiddley with lots of mods necessary. Was I being given the good oil? or are there some LR mechanics who are purists and see tampering with the original design as sacrilage? I live in Darwin and there doesn't appear to be many options when it comes to getting my problem solved. Any help or suggestions would be greatly appreciated. Thanks.

Welcome. Some of us were talking about Unfortunates like yourself, and the consensus of (good natured) advice was... Steal a TARDIS, go back in Time and do your research a bit better this time around...

This all comes from our hindsight...

My Lady Sarah has a huge thirst, but she graciously yields to yours...

Most land Rover victims give their toys a name, If yours is lacking such, may I suggest "Bung" as in the Wizard of Id, the constantly blotto 'Court Jester...

If you look at it from the Old Fashioned Way, of Miles Per Gallon, then you are getting a shade over 8 mpg. Mine gets 15 to 17 mpg. Usually 15.5 on a good day. - She can do better and 3.9's have been known to crack 20mpg

IF you can't convert, try this site:- Litre Per 100 Km Conversion Chart (Fuel Economy Converter, Metric System)

Seriously. Take BeeUtey's advice. Also trawl his past posts for the IGN module conversion and Good Info regarding overhauling your dizzy. Dead vacuum advance units are well-known, and can be replaced/bought in Oz.

Check "compressions" - with apologies to the English language... there ain't too much, as Rover in its Infinite Wisdom made it a LOW compression engine.

You have of course, bought a timing light and advance the spark by at least 10 degrees or just below 'pinging'.

Transmission slippping ? Park brake dragging ? Wheel alignment? Tyres over-size/under inflated? speedo faulty ? Plug leads? Plugs ? The Gods on Mt Olympus hate you?


'Diesel' is the way to go. Here's a pic of the little people-mover I last filled up.
- Took 184 litres for 835km, about 22 litres per 100km. Or 4.53km/l, = 12.8 MPG
Weighs 9.6 tonne, empty, and carries 57 passengers.
To be fair, it was only loaded for 1/2 of those k's...

And, being a Mercedes may have something to do with it !

Thanks for the assistance gentlemen. I really bought a pig in a poke when I was sold this vehicle. I have next to no experience with petrol engines and none what-so-ever with all this (for me) fancy electronics. My previous car was a 1974 Series 3 with a perkins donk in which I clocked up over 500k without too much trouble, all the while sipping diesel. I should have never sold her.
Next step - acquire a timing light.....and see what happens. Also checked the rego, it's a 1994, so it should have a distributor. I'll update the info and yell for help if more is needed. Thanks again.

1994 is the last run of the classic RR. it should have electronic ignition rather than a distributor.