1HD-T vs HZJ (turbo?)

[Dougal]

I have a hard time believing this when companies like Toyota, Isuzu, and Mercedes found it worthwhile to produce both types of engines at the same time.

That being said, if anyone wants to trade a 1HD-FT for my turbo 3B, I'm in!

Back in the 90's IDI gave a smoother, quieter, engine and a wider rev range. Less like a truck engine. They also ran better on contaminated fuel.

Direct injection diesels really took over when turbochargers got better and gearboxes got stronger. The Euro companies (Peugeot HDi, VW TDi, Landrover Tdi etc) also got this sorted earlier with Japanese holding onto IDI for much longer. Some companies still make small industrial IDI diesels!

Personally I refuse to own any IDI diesels.

 

[sodafeld1]

Back in the 90's IDI gave a smoother, quieter, engine and a wider rev range. Less like a truck engine. They also ran better on contaminated fuel.

Direct injection diesels really took over when turbochargers got better and gearboxes got stronger. The Euro companies (Peugeot HDi, VW TDi, Landrover Tdi etc) also got this sorted earlier with Japanese holding onto IDI for much longer. Some companies still make small industrial IDI diesels!

Personally I refuse to own any IDI diesels.

For efficiency? less polluting?

 

[Eurasiaoverland]

I have a hard time believing this when companies like Toyota, Isuzu, and Mercedes found it worthwhile to produce both types of engines at the same time.

That being said, if anyone wants to trade a 1HD-FT for my turbo 3B, I'm in!

Well engineering is not about belief. They were still making steam engines when diesel electrics were already entering service - optimal engineering is not the only consideration when it comes to companies making and selling things.

I guess that depends on what you consider to be an advantage....

Indirect injection diesel engines by their design are so much smoother and quieter, have a broader range of torque, continue to make power right up till redline easier, can achieve much faster engine rpm and have so much more idle/off boost torque with their much higher compression ratio which is awesome for off road use. IDI does have its draw backs though and the fuel economy/engine efficiency, emissions and cooling issues ended up being prioritised which lead to DI taking over in certain countries with higher emissions and consumer demands. That being said and what many don't realise is that DI produces a lot more NOx then IDI which is why EGR/SCR is so common and also as a side effect DPF due to NOx and soot having an inverse relationship to each other. When you make a change in the combustion process to reduce NOx you unfortunately increase soot/particulate matter, hence DPF now needed.

It was perhaps a brash statement on my part and I don't want to get too pedantic, but those are potential advantages in application. An engine is there only to do work - in the case of an IC engine, to convert heat into motion, so it is judged above all else in engineering terms by its thermal efficiency, and perhaps simplicity of design.

I'm not sure I would call IDI engines 'so much' smoother and quieter than DI, but the advantages in quietness, low speed torque, lower NOx are just the result of the pre-combustion chamber and lower combustion turbulence, i.e. they are there because the engine is less efficient.

DI engines are far better suited to forced induction, and it would be hard find an advantage of a NA IDI when compared to a turbo DI diesel.

Back in the 90's IDI gave a smoother, quieter, engine and a wider rev range. Less like a truck engine. They also ran better on contaminated fuel.

Direct injection diesels really took over when turbochargers got better and gearboxes got stronger. The Euro companies (Peugeot HDi, VW TDi, Landrover Tdi etc) also got this sorted earlier with Japanese holding onto IDI for much longer. Some companies still make small industrial IDI diesels!

Personally I refuse to own any IDI diesels.

I remember reading years ago that DI engines really came of age when computers became advanced enough to handle the computational fluid dynamics required to model efficient DI combustion.

I remember when the first Peugeot/VAG DI turbo diesels came out and totally changed the diesel experience. The 1.9 Peugeot diesel gave far more power, torque and massively improved efficiency compared to my 2.4L 2L.

 

[Dougal]

For efficiency? less polluting?

IDI efficiency sucks. It's about 20% less efficient than direct injection due to the heat-loss to the head. The closest I've ever seen IDI vs DI efficiency was I think the Isuzu 4L industrial series which for a short time were available with both. It was under 10% difference.

The best petrol engines beat the worst IDI diesels for efficiency.

For pollution. IDI puts out less soot, but more fines. I find IDI stinks because of that.

Well engineering is not about belief. They were still making steam engines when diesel electrics were already entering service - optimal engineering is not the only consideration when it comes to companies making and selling things.


It was perhaps a brash statement on my part and I don't want to get too pedantic, but those are potential advantages in application. An engine is there only to do work - in the case of an IC engine, to convert heat into motion, so it is judged above all else in engineering terms by its thermal efficiency, and perhaps simplicity of design.

I'm not sure I would call IDI engines 'so much' smoother and quieter than DI, but the advantages in quietness, low speed torque, lower NOx are just the result of the pre-combustion chamber and lower combustion turbulence, i.e. they are there because the engine is less efficient.

DI engines are far better suited to forced induction, and it would be hard find an advantage of a NA IDI when compared to a turbo DI diesel.


I remember reading years ago that DI engines really came of age when computers became advanced enough to handle the computational fluid dynamics required to model efficient DI combustion.

I remember when the first Peugeot/VAG DI turbo diesels came out and totally changed the diesel experience. The 1.9 Peugeot diesel gave far more power, torque and massively improved efficiency compared to my 2.4L 2L.

The DI engines got quieter and smoother when dual stage injectors were developed. The 1HD-T was one of the first engines I know of which had these but landrover TDi, Peugeot, Fiat and VW may have had something earlier. Then we got computer controlled rotary pumps, unit injectors (VW PD, Landrover TD5, Isuzu 4JX) followed by commonrail.

Funnily enough commonrail was one of the first diesel injection systems tried. But the pumps, nozzles and control systems weren't up to it. Took ~100 years to mature.

 

[sodafeld1]

It's interesting upon fuel efficiency and I wish everyone did the same test, with the same speed and carry load. Wind factors is difficult to control though.
Some folks may think I am exaggerating but in my 2h, I can get 9-10l for 100km 1988 troopy only mod is extractors. Moderate 2-300kg load, no roof racks, no a/c. 90-95kmh 2000-2100 rpm no stopping on freeway. Driving like a miserly miss daisy. I think best ever was 8.3l/100km with tail wind. Like clockwork, It makes me happy. ( I don't bother trying to count in start stop traffic, getting moving is the main call for energy).

I watch fuel efficiency here with interest, which is astonishingly high especially for the petrol engines.

Even my wife's 2016 corolla uses the same 10l/100km fuel, admittedly the city run around and petrol does not have the same weight for energy, so more fuel. Not impressive upon fuel really, especially if full of passengers.
Her 93 mazda astina was much more fuel efficient.

My friends 2023 hybrid rav is at best around 4.5l/100km, from memory. But that is a fairly gutless car for carrying weight.
In comparison for what I can do in my troopy to the new rav, I know what I prefer.

The only more modern diesel I have heard of which gets considerably better efficiency is around 7.3l/100 (ish) is in a hilux, I think a kz engine (?) (post 2010?)

The 22r does ok too but a hilux is built much lighter than an lc, and petrol and diesel are just different beasts simply.

My mates hz troopy is faster and more powerful, goes up the hill quicker but does not get the same fuel economy at around 11-12l/100km.

Much depends on driving habits too of course. Yeah I drive slow but I am yet to hear of many di enigines with better fuel economy than what I get.
They sure take off much faster than me, I roll to a stop at the next traffic lights next to them, often.
Convincing anyone to drive in the same manner is another story though!

And well, idi , it's what I got, so naturally my preference. Stinky, dirty bird she is.

But I am all ears for fuel efficiency. I don't know too many engines admittedly. From what I know of the hdfte it is impressive, but I can not imagine it getting under at best 10l/100kms. Have not heard or read about it, but I don't get out much, and when out, I am off.
Ripper discussion here!

 

[Dougal]

It's interesting upon fuel efficiency and I wish everyone did the same test, with the same speed and carry load. Wind factors is difficult to control though.
Some folks may think I am exaggerating but in my 2h, I can get 9-10l for 100km 1988 troopy only mod is extractors. Moderate 2-300kg load, no roof racks, no a/c. 90-95kmh 2000-2100 rpm no stopping on freeway. Driving like a miserly miss daisy. I think best ever was 8.3l/100km with tail wind. Like clockwork, It makes me happy. ( I don't bother trying to count in start stop traffic, getting moving is the main call for energy).

I watch fuel efficiency here with interest, which is astonishingly high especially for the petrol engines.

Even my wife's 2016 corolla uses the same 10l/100km fuel, admittedly the city run around and petrol does not have the same weight for energy, so more fuel. Not impressive upon fuel really, especially if full of passengers.
Her 93 mazda astina was much more fuel efficient.

My friends 2023 hybrid rav is at best around 4.5l/100km, from memory. But that is a fairly gutless car for carrying weight.
In comparison for what I can do in my troopy to the new rav, I know what I prefer.

The only more modern diesel I have heard of which gets considerably better efficiency is around 7.3l/100 (ish) is in a hilux, I think a kz engine (?) (post 2010?)

The 22r does ok too but a hilux is built much lighter than an lc, and petrol and diesel are just different beasts simply.

My mates hz troopy is faster and more powerful, goes up the hill quicker but does not get the same fuel economy at around 11-12l/100km.

Much depends on driving habits too of course. Yeah I drive slow but I am yet to hear of many di enigines with better fuel economy than what I get.
They sure take off much faster than me, I roll to a stop at the next traffic lights next to them, often.
Convincing anyone to drive in the same manner is another story though!

And well, idi , it's what I got, so naturally my preference. Stinky, dirty bird she is.

But I am all ears for fuel efficiency. I don't know too many engines admittedly. From what I know of the hdfte it is impressive, but I can not imagine it getting under at best 10l/100kms. Have not heard or read about it, but I don't get out much, and when out, I am off.
Ripper discussion here!

That hilux will be a 1KD which was as good as it got. The 1KZ was done by 2003. The engine that replaced the 1KD (2014+) is far worse for economy. It appears Toyota meeting more stringent emissions took a big toll.

The 1HD-FTE efficiency depends a bit on the generation. The first ones in the 100 series run the most advanced timing and are the most efficient from the factory. The update which came with the 5 speed auto is more retarded and chews more fuel. Unless someone has been in and advanced the timing. You can get 10km/l from an advanced FTE. Otherwise it's 9km/litre (11 litres/100) on a flat road.

One of my family replaced a 100 series 4sp auto (bone stock) with a landrover Disco 4 (3.0tdv6). Disco weighs about 400kg less (2.4 vs 2.8 ton) and burns only 2/3 of the diesel (average 8 vs 12). My 3.0 td Isuzu ute (4JJ1) burns even less but it's manual 6sp. I get under 7 litres/100km on hilly drives and can tow a box trailer or boat for less than 9.5 litres/100. It's astounding. But also runs so far advanced it "grumbles".

The 2H engines getting good economy is kinda related to the speeds they can travel at.

 

[sodafeld1]

That hilux will be a 1KD which was as good as it got. The 1KZ was done by 2003. The engine that replaced the 1KD (2014+) is far worse for economy. It appears Toyota meeting more stringent emissions took a big toll.

The 1HD-FTE efficiency depends a bit on the generation. The first ones in the 100 series run the most advanced timing and are the most efficient from the factory. The update which came with the 5 speed auto is more retarded and chews more fuel. Unless someone has been in and advanced the timing. You can get 10km/l from an advanced FTE. Otherwise it's 9km/litre (11 litres/100) on a flat road.

One of my family replaced a 100 series 4sp auto (bone stock) with a landrover Disco 4 (3.0tdv6). Disco weighs about 400kg less (2.4 vs 2.8 ton) and burns only 2/3 of the diesel (average 8 vs 12). My 3.0 td Isuzu ute (4JJ1) burns even less but it's manual 6sp. I get under 7 litres/100km on hilly drives and can tow a box trailer or boat for less than 9.5 litres/100. It's astounding. But also runs so far advanced it "grumbles".

The 2H engines getting good economy is kinda related to the speeds they can travel at.

Yeah kd , that 's it, sorry. You know your stuff matey! This is all good knowledge to share.
I think the particulate filters choked ice manufacturers cross the board. I can't possibly understand they think they can save the planet by making more sh#t to throw away.

Even my stihl hedger has a screen which I have to take out and burn clean or it runs horribly, can't breathe.

Good to hear about the hdfte, I would still hate to service those injectors in price comparison to idi.

Yes weight is a huge factor but aluminium does not like being bent back into shape, advantages and disadvantages..

Isuzu sounds a ripper. Mate of mine recently inherited one of the older isuzu utes, pretty nimble with low torque, steel bumper too. Very neat and sweet.

Much respect voodoo!

 

[iliketrucks]

I like dougals point about multi-stage injectors. That's something that has always intrigued me, but I don't often hear much discussion about it.

The idea of having DIs efficiency, but bringing it closer to IDIs noise/smoothness levels using that type of injector sounds like a good design-and it stays fully mechanical! Of course this comes with a tradeoff of simplicity, but it seems like performance and simplicity fall on a spectrum, and it's going to depend on what you value more.

In practice though the only toyota diesels I've been around are IDI B series. I wonder how the NVH compares between an old IDI (2H) and DI with multistage injectors (1HD-T)? I may sound like a wimp, but my 40 series does not isolate me from what's under the hood, on an 8 hour road trip this stuff starts to matter!

 

[sodafeld1]

Is there a di with mechanical injectors?

 

[mudgudgeon]

Yes

12ht, 1HD-T
And other engines of the same era from toyota, and most other major manufacturers

 

[Eurasiaoverland]

I like dougals point about multi-stage injectors. That's something that has always intrigued me, but I don't often hear much discussion about it.

The idea of having DIs efficiency, but bringing it closer to IDIs noise/smoothness levels using that type of injector sounds like a good design-and it stays fully mechanical! Of course this comes with a tradeoff of simplicity, but it seems like performance and simplicity fall on a spectrum, and it's going to depend on what you value more.

In practice though the only toyota diesels I've been around are IDI B series. I wonder how the NVH compares between an old IDI (2H) and DI with multistage injectors (1HD-T)? I may sound like a wimp, but my 40 series does not isolate me from what's under the hood, on an 8 hour road trip this stuff starts to matter!

I think we're talking small differences, for example comparing an HZJ80 with an HDJ80, you'd probably need a stethoscope and a noise meter to make the point.

There are many types of vibration/noise coming from an engine, different orders of mechanical vibration, combustion noise, induction noise. I would guess that only combustion noise is relevant in the IDI vs. DI discussion.

The difference between a 4 cylinder and 6 cylinder comes down largely to first and second order vibrations, which are narurally balanced in an I6, making the engine far smoother than an inherently imbalanced I4. So an agricultural B diesel is going to be noisy regardless of injection system. And in a 40 Series with basically no insulation, I think the IDI vs. DI noise consideration would be irrelevant.

If I compare my 3BII with my 15B-T, I actually thought the latter (DI) was smoother and quieter, and that was running on the floor with no exhaust pipe.

Is there a di with mechanical injectors?

Toyota's first, as far as I know, was the 13B in 1984, then the 11B and 12H-T the following year.

The 14B and 15B platforms are also mechanically injected DI diesels, and the 14B is still in production.

Pre-common rail, mechanically injected diesels are the sweet spot for me.

 

[sodafeld1]

Learning stuff. So often keeps coming back to the 12ht for me, shame about sourcing parts.
My 2h sounds like a tractor, performs like one too

 

[Bisonthecruiser]

Touching briefly on the OP's thread.... Man, get a troopy and put in anything but a toyota diesel into it. I've gone down the 1hdt route. As others have said, you're not going to get a mechanic to touch it, so you'll have to get it home. I had this happen multiple times when I was in my mid-20s and the damn thing destroyed my salary. Injection pump, top end rebuild, filtration system, you name it. I lacked the skills at the time or know-how to work on the rig (I installed the intercooler, etc., but still) and then spent a few years watching it sit at Mudrak (who helped) and then reaching out to Valley Hybrids for help only to realize that if you want to drive one of these, you have to work on it yourself unless you're made of time and money. Same experience on older 7.3 diesels in a van format. Get ready to wrench yourself. At this stage, i'm going to get a turbo installed on the trusty 1fze and enjoy things knowing that any competent mechanic can and will touch it. Your mileage may vary, but an exotic Toyota is more of a PITA to own than a Porsche.

 

[sodafeld1]

Yeah good point, is the op going to work on it themselves.? Ovalooker? Sorry for the hijack.
Folks I know down here including myself, always say you wouldn't own one unless you don't mind getting spanners out yourself. Either that or you are made of money and/or very good friends with a mechanic who likes cruisers.

If I was a pro mechanic, I probably would want it simple and straight forward as possible, maintenance, parts, factory stock. Not some crazy frakenstein, someone else's love. Or you would pay for the extra time it takes.

Personally I could not afford to have a cruiser unless I do the work. In which , overall, I think why ih8mud is an excellent place, someone here shall help you out, free of charge.

 

[jayp2]

Put some mud tires on the 40 and you wont notice the engine......with or without the exhaust.....

 

[GTSSportCoupe]

Great thread!

This is all what I've been preaching for years, and also why all Toyota's factory IDI+turbo engines have cylinder head issues related to heat (not just 2LTE, but 3CTE, 1KZTE, and others).

If you just cruise around in your 1HZ turbo cruiser on weekends loving the noise and scenery, you'll be fine. But putting it to work towing you'll have no end of grief; especially in North America trying to do highway speeds.

I'm looking at 200 series with 5.7 as my next car. Probably one of the more capable cruisers when it comes to towing. (4.5 diesel would be nice, but never came to North America).

 

[JuanJ]

Great thread!

This is all what I've been preaching for years, and also why all Toyota's factory IDI+turbo engines have cylinder head issues related to heat (not just 2LTE, but 3CTE, 1KZTE, and others).

If you just cruise around in your 1HZ turbo cruiser on weekends loving the noise and scenery, you'll be fine. But putting it to work towing you'll have no end of grief; especially in North America trying to do highway speeds.

I'm looking at 200 series with 5.7 as my next car. Probably one of the more capable cruisers when it comes to towing. (4.5 diesel would be nice, but never came to North America).

Hello,

Some 200 Series with the 1VD engine may be already eligible for import to Canada. Twin turbo and other stuff...

Just saying...





Juan

 

[GTSSportCoupe]

Hello,

Some 200 Series with the 1VD engine may be already eligible for import to Canada. Twin turbo and other stuff...

Just saying...





Juan

Yes, I've been drooling over those too