Would you strap a turbo kit to a 1hz with 700 k km's + on the odo ??? (1 Viewer)

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I used to ask myself the same question 7 or so years ago when the vehicle was at 600 k km's and never could really resolve the issue in my head.

According to the people at Berrima Diesel, if the motor does not have any blow-by it's ok to turbo it, but I'm a little hesitant due to the high life and potential wear factors.

So would you or would you not fit a turbo kit to a 1hz with a lot of km's on it? The idea is to increase airflow into the motor to assist it under load for more efficient combustion of the fuel input, not to create a 0 to 60 2.5 tonne weapon or a 3.5 tonne caravan towing road nazi. ;)

What would be your parameters?
 
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Yes absolutely, and if it blows for whatever reason swap another cheap 1hz in. They aren't worth much these days, at least in Aus.
 
Thx for the vote of confidence. One good thing with 1hz is they're everywhere, as are parts for them.

Now the perennial question - which turbo kit(s) to consider? Berrima Diesel seems to use DTS kits with a Mitsubishi turbo instead of the factory CT-26 that a 1hdt motor has.

There are plenty of suppliers of similar kits because it's a big deal here to consider turbo-ing the rugged 1hz toyota motors here.

I wouldn't be looking to replace the existing injector pump as it doesn't have any leaks and was fitted at 510 k km's but I will be replacing the injectors regardless as I have a full new set.
 
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I'd suggest sourcing a new ($300-ish), or a used (if you can find one) 1hd-t exhaust manifold, and see if you can find a good used 1hdfte turbo on Facebook marketplace, find etc
Or mambatek turbo
 
Thx for the vote of confidence. One good thing with 1hz is they're everywhere, as are parts for them.

Now the perennial question - which turbo kit(s) to consider? Berrima Diesel seems to use DTS kits with a Mitsubishi turbo instead of the factory CT-26 that a 1hdt motor has.

There are plenty of suppliers of similar kits because it's a big deal here to consider turbo-ing the rugged 1hz toyota motors here.

I wouldn't be looking to replace the existing injector pump as it doesn't have any leaks and was fitted at 510 k km's but I will be replacing the injectors regardless as I have a full new set.
I had the DTS kit on a 1hz and I didn't like it if I'm honest. It's not a good turbo for the 1hz, builds boost late and I found it had no more in the top end compared to the CT26.

@mudgudgeon suggestion of the FTE turbo is a really good starting point imho.
 
To be honest, I personally would leave the 1HZ N/A as Toyota intended. Its greatest strength is its simplicity. Chucking a turbo on defeats the purpose IMO. I also feel, and this is subjective, but if you're not happy with the response when you put your foot down in the 1HZ without a turbo, you're not going to be satisfied with the results of putting a turbo on if it's kept within a "safe" level, and if you push it beyond that, stuff will start to break.

If I was looking for a turbo, I'd save up my pennies and get a factory 1HD-FT. I believe the 1HZ is a champion of reliability. I think the 1HD-FT is about as good as it'll get keeping to those roots of reliability while trying to get a bit more oomph, and from that platform you can start your mods (intercooler, exhaust, etc) to push it further than you get in stock form, knowing you've got some headroom to experiment.

All this is just my preference though, it depends what matters more to you. I didn't buy an 80 to win drag races, and I've never found the 1HZ leaving me wanting for torque when I needed it. That being the case, I prefer to keep it stock and well maintained.
 
if you're not happy with the response when you put your foot down in the 1HZ without a turbo, you're not going to be satisfied with the results of putting a turbo on if it's kept within a "safe" level, and if you push it beyond that, stuff will start to break.

Putting a turbo on my hzj105 completely changed the way it drove. Absolutely night and day.
 
Thanks for the honest opinions. I'm trying to buy a house at present to try and stop renting, then the 80's diesel engine future gets considered. Agree with 1hz being reliable due to simplicity. I was considering a turbo kit because it's much cheaper than any 1hdt or 1hdft source (import or otherwise) and I can do all the work myself apart perhaps from any adjustments to the injector pump to fine tune it.

I do see the validity of the 1hdt or 1hdft route, and that is actually the number 1 most common upgrade path for 80's and 75's with 1hz's here. Esp 1hdt's as like 1hz's the Aus market is flooded with them. 1hdft not so much but still a lot here.

One thing I don't understand though - turbo'ing seems to have two schools - main one being as much power as possible and the other one just seems to be making an improvement to make it better without going hardcore on getting as much power as possible. Why do you have to aim for as much power as possible if you don't need that? Isn't 'just making it better' a valid goal too?
 
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One thing I don't understand though - turbo'ing seems to have two schools - main one being as much power as possible and the other one just seems to be making an improvement to make it better without going hardcore on getting as much power as possible. Why do you have to aim for as much power as possible if you don't need that? Isn't 'just making it better' a valid goal too?

You could read things differently as two schools being,

Old school.
Minimal boost, more fuel, repurposed readily available old tech turbos, fitted with adapter plates and patched into existing exhaust.
Pyrometer post turbo, (if at all) cause it's easy to weld a threaded bung into exhaust pipe
Intercooling to try to stop overheating caused by low boost and over-fueling.
The idea that boost kills the engines.

New school.
More boost, 15-20 ish psi. because more boost equals more air, more oxygen available to make better use of the increased fuel.
New tech, more efficient turbo, designed for 4.2 litre diesel.
Efficient turbine design requires less fuel to get them to spool up.
New 3" free flowing exhaust to reduce the exhaust manifold pressure required to turn the turbo. No back pressure in the exhaust to restrict gasses escaping through the turbine.
Install boost compensator on the fuel pump to give better ramped control of fueling in off idle/ on boost conditions.
Pyrometer in the exhaust manifold before the turbo for truer readings.
Understanding that heat in the combustion process, heat in the head is what kills them. Tune appropriately to manage heat in the head.
Intercooler to increase air density, and improve efficient combustion of fuel, more complete fuel burn, less fuel required to make power.

Or,
Third school,
Go silly! High boost, if she dies, it was a wild ride while it lasted! 🤪

Turbo choice, and appropriate supporting modifications, and sensible tuning are the key.
 
Simpson off-road engineering makes an adaptor for the stock 1hz manifold so you can use it with a ct26. They can also supply oil and water lines too.

I may or may not have a kit sitting on my bench.

Ok thanks - didn't know about that. Is a factory CT-26 'better' than a non OEM turbo kit? What aftermarket turbo's are based on the Toyota CT-26 product?
 
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Ok thanks - didn't know about that. Is a factory CT-26 'better' than a non OEM turbo?

How long is a piece of string?

Is OEM string better than any other non OEM string?

CT26 is 40 year old technology.

It will still work just fine, but there's other options that are more efficient.

More efficient meaning less fuel needed to drive the turbo. Less fuel burnt for the same power output, less heat in the combustion cycle.
 
Well, better is relative, as muddy sorta said. Its probably used/used up, but its likely cheaper? Really depends on the route you take. But yeah, lots of turbos are loosely based on the CT26.

I'm looking at forced induction to combat the altitude I live at. I've been sitting on an 1HDT turbo and other factory bits for almost a year while I get everything else optimal. I like OEM in this case because its pretty much bolt on, once I adapt the manifold. A new OEM air cleaner lid, an OEM plenum, and some hoses/clamps. My plan is to add enough boost to be able to turn the fuel back up to what is stock at sea level, while maintaining current EGT's and (non) smoke levels. Currently I'm running super lean for day to day driving at 3600 feet and above. (I did add an HAC to the top of the pump).

Turbo additions are about as polarizing as oil or tire choice, so look at your specific needs/wants, filter through the opinions, and do the best you can for your rig. But my advice (remember what they say about opinions) is to get it running as good as it can n/a first, before ramming any more air down its throat.
 
New school.
More boost, 15-20 ish psi. because more boost equals more air, more oxygen available to make better use of the increased fuel.
New tech, more efficient turbo, designed for 4.2 litre diesel.
Efficient turbine design requires less fuel to get them to spool up.
New 3" free flowing exhaust to reduce the exhaust manifold pressure required to turn the turbo. No back pressure in the exhaust to restrict gasses escaping through the turbine.
Install boost compensator on the fuel pump to give better ramped control of fueling in off idle/ on boost conditions.
Pyrometer in the exhaust manifold before the turbo for truer readings.
Understanding that heat in the combustion process, heat in the head is what kills them. Tune appropriately to manage heat in the head.
Intercooler to increase air density, and improve efficient combustion of fuel, more complete fuel burn, less fuel required to make power.
this ^^
and take care of all deferred maintenance/'when im in there' things like water pump, injectors, complete head re+re ( you will find things), belts hoses, cooling system optimization, glow maintenance, air box flow, possible bottom end bearings.
You must have a complete and comprehensive attitude when changing the operating conditions of the engine to have it be 'reliable'
Dont waste time with slapping an old tech turbo on, buy the best one you can afford even if you arent trying to launch the truck to the moon.
 
I was considering a turbo kit because it's much cheaper than any 1hdt or 1hdft source (import or otherwise) and I can do all the work myself
I would go ahead with it if you can afford to rebuild it or buy a factory turbo engine sometime in the future. The truth is, your 1HZ's best days are behind it, but if you take it easy, you might get a few more years out of it.
Some diesel shops demand a compression test before they will fit a turbo.
I see you are also trying to buy a house, unless you are a Lotto winner, you probably need to prioritise your funds into a roof over your head.
 
True and I got finance pre-approval yesterday morning then got gazumped in the afternoon with one final buyer viewing at 1 pm, making offer at 3 pm and owner accepted that offer at 6 pm. I've rented the house for just over 5 yrs and had been trying to get finance pre-approval ever since house was put up for sale in June.

I'm def compression testing the motor as soon as the kit I've ordered arrives.

I've had people say that after 300 k km's you're running a significant risk turbo-ing a 1hz.
 
I fitted a DTS turbo kit to my 1HZ at 570k. Previously I had fitted a set of pacemaker extractors and ran them for about 300k, they were good, it improved the response and gave me a little extra power. But, nothing extraordinary.
So after much deliberation and reading as many forums and talking to a few diesel turbo specialists, I bought the DTS kit along with a 3" Redback exhaust system, Pulled the sump, welded in a S/S 1/2" nipple and fitted it all up at home.
How does it go? It's like a completely different car to drive!
Firstly, the engine is all original and was never touched until I fitted the kit, original pump, original injectors, never had a valve set done, and even the original water pump. But, the engine has never used oil, it has always been regularly/religiously serviced (filters every 20k and oil at 10k) and has no blow-by, 95% of driving is long miles on the open road and it has always run a little warm when pushed constantly at 130k/hr, I definitely don't nurse this engine. It regularly tows a 20' boat and i'm not scared to push it and hold it on the governor when overtaking or needed.

There are a few fundamentals that you really need to consider,
1/: What condition is your engine really in (good/reasonable/fair/poor),
2/: Get it properly tuned on a reputable dyno where they can get the AFR right (approx 19:1) I used DynoLink in Townsville,
3/: Before you take it to the dyno, fit a new air cleaner and fuel filters, this will give you the most accurate base line and tune, with a bad air filter you can get more soot than usual, with bad or old fuel filters you can get "hunting/surging or flat spots" (set yourself up to get the best result), also if in doubt fit new radiator hoses and clamps as well,
4/: A good dyno tuner will ask what you are after in the tune, outright performance or reliability (both are directly related),
I told the tuner to tune it as if it was his car - for reliability (so boost is set at about 12 - 13 psi) and the AFR about 19/19.5 : 1 and ended with about 170hp, which I'm really happy with (It can get s*** scary on wet roads).

30k later (now 600k), it is still running like a dream. As stated previously, this engine has always run warm when pushed and this is even more evident with the turbo fitted, I haven't changed or upgraded the radiator (yet) although I am considering it when I fit a new water pump (long overdue) and the fan "clutch" has been filled with epoxy then drilled and tapped with bolts fitted, so it is 100% constant direct drive 100% of the time. I get about 5 - 7% better fuel economy and this would probably be a little better if I didn't lock the fan up the way I have. I haven't pushed EGT much past about 650 - 680C on a hard run (getting towards hand grenade territory) and it usually sits between 250 - 300C on the open road @100 - 105k/hr.

If you want to go nuts on a semi custom build, go to Spool Imports, they have a kit with Ross forged racing pistons, Spool H beam rods, super heavy duty gudgeon pins, a selection of performance bearings/valve springs/ARP bolts. Open your pump up, modify your governor to go to 6k, balance and blueprint the bottom end and have some serious fun with 30+ PSI of boost (just a thought)!

Lastly, the stock clutch and gearbox that is standard behind your N/A 1HZ may start to protest with the added power. I have a SafariTuff clutch fitted and when the original box died (spud shaft coupling), I fitted a new gearbox with a fully splined 5th gear and the main shaft now has nearly 3" of spline at the spud shaft coupling between the box and transfer case (this gearbox is starting to give hints that it is at it's limit). I will be really surprised if it lasts more than 150 - 200k (time will tell).

That's it so far, couldn't be happier ! Hope this information helps someone.

Other things
 
never had a valve set done

Meaning never had valve clearances adjusted?

If so, is something I'd highly recommend. I've set valve clearances on both my diesel cruisers with around 200k km. It makes a noticeable difference in the way they perform.
I would imagine even more so at 600k km
 
I fitted a DTS turbo kit to my 1HZ at 570k. Previously I had fitted a set of pacemaker extractors and ran them for about 300k, they were good, it improved the response and gave me a little extra power. But, nothing extraordinary.
So after much deliberation and reading as many forums and talking to a few diesel turbo specialists, I bought the DTS kit along with a 3" Redback exhaust system, Pulled the sump, welded in a S/S 1/2" nipple and fitted it all up at home.
How does it go? It's like a completely different car to drive!
Firstly, the engine is all original and was never touched until I fitted the kit, original pump, original injectors, never had a valve set done, and even the original water pump. But, the engine has never used oil, it has always been regularly/religiously serviced (filters every 20k and oil at 10k) and has no blow-by, 95% of driving is long miles on the open road and it has always run a little warm when pushed constantly at 130k/hr, I definitely don't nurse this engine. It regularly tows a 20' boat and i'm not scared to push it and hold it on the governor when overtaking or needed.

There are a few fundamentals that you really need to consider,
1/: What condition is your engine really in (good/reasonable/fair/poor),
2/: Get it properly tuned on a reputable dyno where they can get the AFR right (approx 19:1) I used DynoLink in Townsville,
3/: Before you take it to the dyno, fit a new air cleaner and fuel filters, this will give you the most accurate base line and tune, with a bad air filter you can get more soot than usual, with bad or old fuel filters you can get "hunting/surging or flat spots" (set yourself up to get the best result), also if in doubt fit new radiator hoses and clamps as well,
4/: A good dyno tuner will ask what you are after in the tune, outright performance or reliability (both are directly related),
I told the tuner to tune it as if it was his car - for reliability (so boost is set at about 12 - 13 psi) and the AFR about 19/19.5 : 1 and ended with about 170hp, which I'm really happy with (It can get s*** scary on wet roads).

30k later (now 600k), it is still running like a dream. As stated previously, this engine has always run warm when pushed and this is even more evident with the turbo fitted, I haven't changed or upgraded the radiator (yet) although I am considering it when I fit a new water pump (long overdue) and the fan "clutch" has been filled with epoxy then drilled and tapped with bolts fitted, so it is 100% constant direct drive 100% of the time. I get about 5 - 7% better fuel economy and this would probably be a little better if I didn't lock the fan up the way I have. I haven't pushed EGT much past about 650 - 680C on a hard run (getting towards hand grenade territory) and it usually sits between 250 - 300C on the open road @100 - 105k/hr.

If you want to go nuts on a semi custom build, go to Spool Imports, they have a kit with Ross forged racing pistons, Spool H beam rods, super heavy duty gudgeon pins, a selection of performance bearings/valve springs/ARP bolts. Open your pump up, modify your governor to go to 6k, balance and blueprint the bottom end and have some serious fun with 30+ PSI of boost (just a thought)!

Lastly, the stock clutch and gearbox that is standard behind your N/A 1HZ may start to protest with the added power. I have a SafariTuff clutch fitted and when the original box died (spud shaft coupling), I fitted a new gearbox with a fully splined 5th gear and the main shaft now has nearly 3" of spline at the spud shaft coupling between the box and transfer case (this gearbox is starting to give hints that it is at it's limit). I will be really surprised if it lasts more than 150 - 200k (time will tell).

That's it so far, couldn't be happier ! Hope this information helps someone.

Other things

Great 1st post by the way. Very informative.
 
Meaning never had valve clearances adjusted?

If so, is something I'd highly recommend. I've set valve clearances on both my diesel cruisers with around 200k km. It makes a noticeable difference in the way they perform.
I would imagine even more so at 600k km
You are correct on both accounts,
I have never adjusted the clearances (or checked them for that matter, 1 follower has always had a slight "tick to it), I lose motivation with shim under bucket, even though I know it's not hard - it's just annoying/painful haha.
And, as you mentioned, it can make a big difference to performance if the are out by a fair degree.
To be completely honest, the reason I haven't bothered, is the performance has been so good so far, I feel it hasn't warranted it (and a % of can't be bothered). On the flat I can wind it out so that it reaches the governor in 5 gear, with a slight/moderate downgrade it reaches the governor pretty damned quick to be honest, so much so that, overtaking trucks, particularly B-Doubles and triples is no longer a white knuckle, arse clenching "will we make it experience" . But, pure fun and exhilaration (relative for a 79 cruiser ute).

A couple of other features that I didn't mention, I fitted an inline spin-on oil filter (cheap and simple) as catch can between the PCB outlet and inlet side of the compressor, to filter out the increased oil mist generated due to the higher negative pressure created by the turbo, and to act as a sort of, restrictor in the line. Even after 30k, I can spin the filter off and turn it upside down and no oil runs out. However, it is is black and oily when you look in it, so just how well it is working could be up for speculation ????
Sitting @100k/hr on the open road, boost sits between 6 - 8 psi. It runs extremely clean with almost zero smoke, so I have found that the oil in noticeably cleaner at oil change intervals, which would correspond to the increased/cleaner combustion (for a simple old school mechanical injected diesel).

1 thing I do hear people ask a lot is, where can they find a 1HDT block and crank, to my knowledge the 1HZ and 1HDT block and crank are identical (from all the cross referencing part numbers and checking casting numbers and dimensions I have done), the only difference being the heavier rods for the 1HDT and that the 1HDT block is drilled and tapped to accept the oil drain back from the factory, where as the 1HZ block has the casting there in the block. However, it is just not drilled and tapped, the heads and injector pump are different although they share the same stud/bolt pattern and coolant/oil galleries (someone correct me if I am wrong).
I would say that it is also very possible and viable to drill and tap it rather than removing the sump the way most do (me included) when installing a aftermarket turbo on a 1HZ, having said that, it is in a pretty tight area though, when the engine is in situ?

Thanks for your comment.
 

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