LJ70 2.4 (or 1KZ 3.0) rpms on motorway, fuel economy, etc.?

[Rusty Bottoms]

Hi all,

First post here and a few questions if I may.

I'm looking to replace my overall brilliant Suzuki Jimny work vehicle (4" lift, 29" ATs) with a 1980s LJ70 SWB 'Bundera' 2.4 2L-T or a mid-90s LJ70 (would this be an import?) with the 3.0 1KZ-T or TE (more miles on the clock but quite a bit more expensive!). I need the extra bit of space now for a baby seat, and my wife sits in the back with the baby so the Jimny flat out doesn't work. I also want something with a bit more torque, e.g. a turbo diesel.

My Jimny turns 3500rpm at 60 with stock tyres, and around 4000 at 65 (!) so I normally run 55-58mph, which doesn't work for long trips! I get 30-34mpg with stock tyres on the Jimny.

For as slow as it is, my Jimny gets really poor fuel economy (only 22-25mpg) with the big 29" tyres - no surprise as the engine has to work harder to keep up with traffic flow, so I only run them for jobs where I'm out in wet or muddy fields most of the day. I go easy on my 4x4 both on and off-road, and keep excellent maintenance, but with a 1.3l motor the laws of physics take over. I can't really use it on the motorway either with the big ATs.

I test drove a 2.4 LJ70 down in England last week for a few minutes and it's definitely no rocketship, but in regards to an LJ70, can anyone please tell me:

-What the engine revs are at 60/65/70 on stock tyres? (265/65/15 with 4:88 gears and .855 5th if I'm not mistaken). Would a mid-90s 3.0 LJ70 have the same gears, or higher gearing/lower revs?

-What kind of fuel economy do you normally get on the motorway or in town?

-What speed feels comfortable on the motorway? 60? 65? 70? Does 65 feel like too many revs?

-Will it run 65mph all day and pull a decent grade on the motorway, if you keep the turbo spinning, or does the 2.4 fall on its face uphill?

I've heard you can adjust the fuel system for a bit more power down low, or run an intercooler, but I am just thinking maximum reliability, plus I don't even own one (yet!).

Any thought/comments greatly appreciated!

 

[Shayne]

I have no experience of the 70 series but engine swaps from 2.4 to 3.0l 1kz seem quite common which tells its own story .

My modified 1kz 90 series would do 90mph all day while staying under 3000prm though the mods have likely hurt fuel consumption i still get somewhere in the early 20's mpg

 

[Rusty Bottoms]

Ah that's good to hear actually. A 1KZ is preferred, but may well end up with a 2LT to start. I won't be going much over 70mph (after the Jimny, 70 will feel like 100!). I just didn't want to fork out a fair bit of money for a nice LJ70 to find that it doesn't cruise much better than the Jimny on the motorway - however improbable that might be. Most dealers I've encountered won't let you take cars too far from the garage on a test drive, so it's a tossup as to how they behave at speed. Regarding fuel economy, anything over 25mpg would be good news for me. I'd go for a larger landcruiser but I can't make the turn down the alley into my drive! Cheers Shayne for the info.

 

[Shayne]

How come the swb 90 series doesn't get a look in ?

 

[Rusty Bottoms]

Good question - I've only seen one swb 90 so far for sale (reasonably low miles as well as decent price), though I haven't looked too hard as I've been largely obsessed with the 70s. I like the older styling of the swb 70, but just saw some photos of a lifted swb 90 and have to say it looks the business. 3.0 lump as well. I'll certainly give it some thought as it would probably work out a bit better in the long term than an older model.

 

[Shayne]

I shouldn't say it but i imagine its a luxury car compared to the LJ and if you can find a d4d fuel consumption is probably into the 30's on a motorway . The 90 is no softy off road either .

 

[Rusty Bottoms]

I imagine you are right. I drove the LJ70 a few days ago, and it felt very solid but was no magic carpet ride. I suspect a 90 would feel quite a bit different. I drive mainly rough tracks and farmers fields for work, try to avoid charging through mud these days, though it depends on my mood! I'll research the swb 90 some more. One interesting thing though, the guy with the lexus transplant 4.0 v-8 LJ70 is selling it quite cheaply. Have you seen this motor before? He has done a TON of work to it and it's super clean, but I don't think it's done many miles since the engine swap, so not sure how reliable the swap-over is. I know the whole fuel economy thing goes out the window here, but that would be one nice 70 once the remaining bugs are ironed out... hmm.

 

[Rusty Bottoms]

It's an early start for me tomorrow, so I'll check emails then if I don't catch you later on today. Thanks for the 90 suggestion!

 

[Shayne]

I am sure the idea of owning a v8 lexus 70 series will have a few members on here drooling !

 

[Rusty Bottoms]

...and me as well! Bring on the early mid-life crisis, you only live once.

 

[Shayne]

Ha i bought a v8 hummer once only kept it a few months but so glad i did it

 

[alexy]

hi,
Ive done 26000km so far in my 2.4lj73.
mind you, 70 has not much storage space, 73 does a little bit better with almost 30cm extra.
more than 100km/h cruising speed is probably too much to ask poor engine to offer.
fuel wise mine managed 8.3l/100km, but city average depends on traffic I guess.

uphill highway its an inertial affair, engine is prone to overheating and cooling system must be kept under close supervision.

a more powerful engine is better if u want speed on highway, surely not a 2lt.

 

[Rusty Bottoms]

hi,
Ive done 26000km so far in my 2.4lj73.
mind you, 70 has not much storage space, 73 does a little bit better with almost 30cm extra.
more than 100km/h cruising speed is probably too much to ask poor engine to offer.
fuel wise mine managed 8.3l/100km, but city average depends on traffic I guess.

uphill highway its an inertial affair, engine is prone to overheating and cooling system must be kept under close supervision.

a more powerful engine is better if u want speed on highway, surely not a 2lt.

Thanks for the information. Yes the 2.4 may not be much of a change from the Jimny cruising speed, maybe a tick faster in its comfort zone. I wouldn't mind a slightly longer wheelbase, but our home access is super tight, was built back when it was horse and again I think! We have good views but poor parking.

 

[Beau]

That 1UZ Lexus lump is actually a very strong engine, and surprisingly light for a V8. It's also very easy to gain some more power from. Fuel millage will depend on how much fun you want to have from it, but I can't see it being that much worse than the 2.4. The major difference is you can cruise comfortably, and put your foot down when you want compared to the 2.4.

Alternatively, like Shayne suggested a 90 series, or the 70 series with the 1kz lump would suit you perfectly.

 

[Rusty Bottoms]

That 1UZ Lexus lump is actually a very strong engine, and surprisingly light for a V8. It's also very easy to gain some more power from. Fuel millage will depend on how much fun you want to have from it, but I can't see it being that much worse than the 2.4. The major difference is you can cruise comfortably, and put your foot down when you want compared to the 2.4.

Alternatively, like Shayne suggested a 90 series, or the 70 series with the 1kz lump would suit you perfectly.

Hi Beau, Yes I'm intrigued by the 1UZ motor. I wouldn't need more power from it, but saw a video of a 1,000hp twin turbo 1UZ in an Ultima GTR kit car, I think he hit 340km/h before standing on the brakes!
A stock 1UZ would probably make a great motoway cruiser and the engine has a solid reputation from what I've read. I got the feeling from my short test drive the 2L-T would end up feeling about the same as the Jimny, power-wise. I'm hoping to pick up a 1UZ LJ70 this weekend, will keep you posted if I get my hands on it. I'm in my middle age, but am feeling like a kid thinking about it.

The only SWB90 I can find at the moment is an autobox which I'm not so keen on, though I've owned a number of cars with automatic transmissions and only one has failed (an ancient 1975 BMW) but I was pretty hard on it - this was years and years ago. Anyway, thanks for the input, I will keep all posted if I get my hands on an LJ70 this weekend before my wife changes her mind...it's taken some delicate negotiation to get her to come around to the idea!

 

[Rusty Bottoms]

Ha i bought a v8 hummer once only kept it a few months but so glad i did it

Sorry Shayne, hit return on my earlier post well before I completed it. I think I've a deal worked out with the v-8 LJ owner, should have it by Sunday if things go to plan! Keep you posted...

 

[Shayne]

Fuel consumption from Hummer V8 was surprisingly good on motorways a regular journey that normally costs about 70 quid in fuel for my kzj90 cost 90 quid in the Hummer and that's with me blipping the throttle constantly like a big kid with a new toy . Around town though fuel consumption was diabolical .

I appreciate the temptation of a V870 but do go into it with your eyes wide open i inquired about a modified V8 defender once and asked about fuel consumption , the reply i got was "if you need to ask you can't afford it"

 

[Rusty Bottoms]

Fuel consumption from Hummer V8 was surprisingly good on motorways a regular journey that normally costs about 70 quid in fuel for my kzj90 cost 90 quid in the Hummer and that's with me blipping the throttle constantly like a big kid with a new toy . Around town though fuel consumption was diabolical .

I appreciate the temptation of a V870 but do go into it with your eyes wide open i inquired about a modified V8 defender once and asked about fuel consumption , the reply i got was "if you need to ask you can't afford it"

Yeah I'm not under any great illusions. I once had a 7.4l 440cu inch Plymouth Roadrunner with pistons the size of buckets and a 5.0 Mustang GT which was heavily modified with a big roller cam. The fuel-injected Mustang did 20-23mpg on a run actually! The temptation is too much though on the V-8 LJ70, if the deal all works out. I'll keep the Jimny for now either way, but even that falls to low 20s with tall all-terrain tyres and speed is abysmal. Fuel economy isn't my overriding concern, I don't do a great deal of miles, and can write off mileage for work, but if I can squeeze 17-20mpg out of a 1UZ LJ70 that would be okay. I've been reading threads on 1UZ engine swaps. If anyone considers it, this guy in NZ wrote a very detailed no-nonsense article: https://drive.google.com/file/d/0B0WE7dVhvJd_UFRKeEptSTVqaTg/edit

- The article is just about general wiring issues meant to add...

Will see what happens this weekend...

 

[Shayne]

Good luck with it then we are looking forward to pics

 

[Rusty Bottoms]

Thanks! The seller seems good, things are set up for Saturday but I think there are some other interested potential buyers. I'm off work rest of week, so might try and make the run down tomorrow. Either way, will let you know... thanks again for all the information everyone!