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4.2 1HZ Engine Performance Characteristics

clivehorridge

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For the very few members out there driving a variety of Land Cruisers fitted with the 1HZ engine, I'm interested in how they perform.

I've had my HZJ80 for 8 years now and it's done 243k kms. It runs smoothly, starts first time, uses no oil, and all the commendable characteristics the mighty straight 6 offers.

However, as has been discussed by many of the HDJ 80 owners, whose trucks boast 130 MPH :lol: and other such nice features of the turbo version, I'm really interested to know if I should be trying to tune my injector pump to get those extra MPH out of my old girl.

From now on I have to talk about KPH because mine's a left hooker (LHD) but as I've posted before, I can't get more than 3,000 RPM in top (high 5th) comfortably, although between the gears it will pull up to 4,300 RPM and on a downhill motorway I did get it to 3,200 which IIRC is about 130KPH.

That suggests no problems with fuel delivery (and I've checked the lines, the scavenger filter in the tank, the injectors, the engine bay filter etc. etc.) and all the usual rest, air filter and the like.

So a poll from the HZJ fraternity would be useful, what RPM should I be aiming to be able to pull in top gear (it's a better gauge than speed I think)?

If it's more than 3,200 (comfortably) then I'll have to consider doing something about it!

Thanks all:icon-biggrin:
 
130mph!!! My 1fzfe prob wouldn't pull that.
 
130mph!!! My 1fzfe prob wouldn't pull that.

Well Gary it was tongue in cheek hence the lol, but the point is, the HDJs do go well with the turbo, and up to and past the 100 MPH mark, so without any feedback I have nothing to compare mine with!
 
I've only driven 2 diesel 80's and they were not pleasant but were sheds. Driven a few petrols though (some not so pleasant ones too)

I'll ask the question elsewhere for you see what comes back.
 
No standard 80 series LC ever made will pull anything like 130mph irrespective of which engine variant it has fitted. Obviously the quickest will be the petrols but even these will be well short. Ignoring the 1PZ versions (if they are any) the non turbo 1HZ versions will probably be the slowest. Bigger wheels/tyres, suspension and body lifts plus oversize bumpers and all the other offroading paraphernalia will also impact top speed significantly so if you have all this fitted there's probably not much wrong with your 1HZ!
 
I did once get 120mph (indicated) with my first 1 HDT 80.
 
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I've only driven 2 diesel 80's and they were not pleasant but were sheds. Driven a few petrols though (some not so pleasant ones too)

I'll ask the question elsewhere for you see what comes back.

that would be great Gary, thanks!

i don't want to be chasing something if my truck is normal, I just want it to be performing as it should!
 
No standard 80 series LC ever made will pull anything like 130mph irrespective of which engine variant it has fitted. Obviously the quickest will be the petrols but even these will be well short. Ignoring the 1PZ versions (if they are any) the non turbo 1HZ versions will probably be the slowest. Bigger wheels/tyres, suspension and body lifts plus oversize bumpers and all the other offroading paraphernalia will also impact top speed significantly so if you have all this fitted there's probably not much wrong with your 1HZ!

Thanks Towpac! As I've said, I just want to know! There's no good or bad news to me, I'm quite satisfied with the performance of my truck!

I'm old, so is she, but both of us want to perform as we should be, that's all! :lol:
 
I did once get 120mph (indicated) with my first 1 HDT 80.

You see Chas, it's all about comparisons. That's some 193 kph, which is 60 better than my best!
 
You see Chas, it's all about comparisons. That's some 193 kph, which is 60 better than my best!

That was indicated on the speedo though and we know they are optimistic. :icon-wink:
 
I know most refer to them as slugs but mine goes well, wont win any speed records but with 285 tyres, all the racks and bumpers it holds it own on the roads here with no worries. Not sure on the top speed but on the highway here you can only do 110kph.
 
I know most refer to them as slugs but mine goes well, wont win any speed records but with 285 tyres, all the racks and bumpers it holds it own on the roads here with no worries. Not sure on the top speed but on the highway here you can only do 110kph.

Thanks Paul. :thumbup:

My my problem is, it will do 100kph in 4th, then when I change into 5th it's so slow to get to 120kph and that's about it's limit, apart from a downhill with a wind behind it!

Maybe that's how it should be, I'm OK with that, but I just want to hear it from others.

Thanks for posting.

PS The IoW holds great memories for me, my Mother was born in Ryde, most of my childhood memories are from Wootton and Woodside beach!
 
I didn't get much response apart from 110kmh in 5th 2200 rpm.
Other then that it was are you trying to blow it up lol.
 
I didn't get much response apart from 110kmh in 5th 2200 rpm.
Other then that it was are you trying to blow it up lol.

I'd be the saddest 80 owner on the planet if I did Gary! :doh:

2,200 RPM sounds a bit low for 110KPH, but I suppose tyre sizes and diff ratios all come into play here. Mine's a manual with 33" tyres, if that equates to anything.

Anyway, from the responses, mine seems to be par for the course, and I won't waste any efforts trying to fix something that's not broke!

110 kph is fine for me, on these roads with a 100kph limit. Thanks guys! :thumbup:
 
Just don't have a go in a 1fz mate lol.
 
Did someone say turbo kit?
 
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Seeing the above here is my tuppence worth, changing from 4th to 5th at about 60/65 mph my truck still accelerates in 5th like she does in 4th, and on the flat it pulls to about 3500 rpm in 5th. I believe the quoted top speed for the diesel 80 by rpm to gear ratio is 109 mph and I have got an indicated 110 mph on the german autobahn, if memory serves me correctly. I am running 285 75 16 profile tyres.
 
Seeing the above here is my tuppence worth, changing from 4th to 5th at about 60/65 mph my truck still accelerates in 5th like she does in 4th, and on the flat it pulls to about 3500 rpm in 5th. I believe the quoted top speed for the diesel 80 by rpm to gear ratio is 109 mph and I have got an indicated 110 mph on the german autobahn, if memory serves me correctly. I am running 285 75 16 profile tyres.

Ah, ha! This isn't tuppence worth Julian, it's a major turning point in my relationship with my truck! :wtf:

I'm running heavy with ARB front and rear bumpers + winch, wind drag and weight of a full length ARB roof rack, and the drag from 10" x 16" steel wheels shod with 305/70/16s (32.8" or thereabouts) and I appreciate that these will prevent me from pulling 3,500 RPM in 5th.

But, I can barely get it above 3,000 at the moment on the level which is appx. 110-120 kph using a GPS speed reading.

As I said, I've checked everything that I can check, which includes checking the valve clearances and injectors, so I think my only next option is to get the injector pump settings checked/adjusted.

I'm really not looking for speed, just to be confident that the engine is running at optimum, which I don't think it is at present.

Should I be looking elsewhere before I turn my attention to the pump?

Finding a competent guy here in Bucharest will not be easy, and he won't be too familiar with the 80 diesel (there's not many of them here) but if needs must, I'll find him... :icon-biggrin:

Any any good advice will be welcomed Julian, thanks for posting :thumbup::thumbup:
 
I think you can still relax Clive ... if Julian is talking about the truck in his signature he will have a 1HD-FT so not a fair comparison.
 
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