The 2H/12H-T/1HZ/1HD-T/1HD-FT Gturbo Alternative Tech Thread (3 Viewers)

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Thanks for the input as the reason for this thread was to give folks affordable viable alternatives for these engines. It would be interesting to know how UFI's turbine housings are modified.
 
I have a few ideas planned mainly out of curiosity.
Thinking the big 16G mated to the ct26 is going to be my ticket.


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I was actually looking at Dougal's idea of the Td04hl, but maybe I'd build with a billet 20t wheel, anti surge housing and volvo angle exit housing. Could work pretty good I think. All just ideas at the moment.

So you'd keep the ct26 turbine stock and upgrade the comp wheel only? What's the advantage of the 16G vs some of the more standard CT26 hybrids (50-57 etc?)

I may just build a mild ct26 hybrid for now, then go crazier later....hmm.
 
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the 16g big wheel is a 50 trim wheel and is a little bigger than the supra comp wheel.
I would rep the stock turbine at this point.
If it chokes out, more flow is needed, though I doubt this will happen.

both have the same shaft diameter so it would essentially be a comp wheel addition, balancing job, comp housing machining.
 
Bigger is not better guys. Compressors need to be the right size or performance and efficiency turns to custard.
 
I'd have to say that unless the turbine side or housing is changed I don't think much would change performance wise. Well at least not drastically. Ohh and on that note.... I'm going to Disney Land! My wife and kids are coming too by the way.
g
 
sorry for the sidetrack guys ,but gerg ,thats a drag the family is going this time , make the best of it doc. he he.
 
I havent been on for ages either. And this does seem a little disrespectful IMHO. What your trying is nothing new at all (and best of luck to you). We have tried all manner of turbo combinations and brands here in australia. The simple fact is it took 20 odd years (since these engines where released) for someone to design and build a turbo that fits the bill perfectly that everyone is happy with.. for landcruiser TD's. I mean patrols have been killing us for years!!! and only now are we catching up. And for 1 main reason. The turbo spool and efficiency is the heart of all performance. If any of us where going to design a turbo, we would so it spools as early as possible from as little exhaust gases as possible - Any turbo can spool early enough if you throw enough fuel at it (Like I read from this ATEB place etc). But its false economy, you may aswell disconnect your compensator and wind the thing out. So far the models quoted are going to be far from perfect, but good on you for having go. But I wouldnt want to waste money trying them. IMHO you cant get any better than a Gturbo. And there is no close second. Second is still light years behind when comparing side by side.
This is a bayboy turbo (good for 30psi) in a 1HDFT spooling from 22:1 afr's through out.
 
I'm surprised no one has mentioned the Toyota CT15B from the late model single turbo 1JZGTE (2.5l disp). Seems to me it would be a nice swap to the 1HDT. Being ceramic, it's not suitable for those chasing high pressures though. It is regarded as one of the best turbochargers Toyota ever made.
 
I'm surprised no one has mentioned the Toyota CT15B from the late model single turbo 1JZGTE (2.5l disp). Seems to me it would be a nice swap to the 1HDT. Being ceramic, it's not suitable for those chasing high pressures though. It is regarded as one of the best turbochargers Toyota ever made.

Being a Toyota part, there are no compressor or turbine maps, no alternate size housings and even parts like rebuild kits can be a huge problem.

Why bother when there are better supported turbo families?
 
I did find this little diagram awhile back and wanted to resurface this thread.

Just as an example between Turbine Wheel Size again.

Turbine Wise
CT26 52mm / 68mm with 10 blades
TD05H 49mm / 55.8mm 12 blade
TD06H58.8mm / 67.3mm 12 blade

Is it safe to assume that the CT26 being in the middle of the two wheel sizes would preform similar to this if the three of them were all running the same compressor wheel?


IMG_0459.webp
 
I'm surprised no one has mentioned the Toyota CT15B from the late model single turbo 1JZGTE (2.5l disp). Seems to me it would be a nice swap to the 1HDT. Being ceramic, it's not suitable for those chasing high pressures though. It is regarded as one of the best turbochargers Toyota ever made.

Also for the 1hd-fte. I am sure it would perform fantastic.
Can get them in inconel so you don't have to worry.
Got a hybrid already in mind for one :steer:
 
Also for the 1hd-fte. I am sure it would perform fantastic.
Can get them in inconel so you don't have to worry.
Got a hybrid already in mind for one :steer:

Right on, I look forward to hearing/seeing more about what you're up to. I did read somewhere about someone putting a straight up CT15B onto a Toyota diesel with very good success. Can't remember where or what though.
 
for people that are curious between the CT26 and the CT15B they share the same CHRA.
Internals would require different bearing kits between the two turbine wheels as they are different size shafts.
It seems that the Toyota CHRAs are interchangeable for peoples information.

Turbine speaking
CT26 52mm/68mm
CT20B 50mm/60mm
CT15B 48mm/60mm
They all are 10 blade turbines.

With the stock CT26 if you were to do supra hybrid upgrade just as an example your flows would be increased mainly because the wheel size is increased over stock because the compressor is able to move more air than the smaller stock compressor.
Putting on a smaller turbine would create a faster spool in comparison to its larger counter part.

I have a few ideas floating in my head right now and I plan on testing a few combinations.
Even just an anti surge cover and the custom billet wheel on the stock CT26/housing of say the 1hd-t is going to be excellent performance over stock.
I think one of the fancy custom billet wheels/anti surge housing with a turbine upgrade to say a 15B turbine/housing will prove some excellent performance at a very reasonable cost. It would cost more mainly because you would have to source a new turbine an turbine housing over just buying a comp wheel/comp housing.
 
for people that are curious between the CT26 and the CT15B they share the same CHRA.
Internals would require different bearing kits between the two turbine wheels as they are different size shafts.
It seems that the Toyota CHRAs are interchangeable for peoples information.

Turbine speaking
CT26 52mm/68mm
CT20B 50mm/60mm
CT15B 48mm/60mm
They all are 10 blade turbines.

With the stock CT26 if you were to do supra hybrid upgrade just as an example your flows would be increased mainly because the wheel size is increased over stock because the compressor is able to move more air than the smaller stock compressor.
Putting on a smaller turbine would create a faster spool in comparison to its larger counter part.

I have a few ideas floating in my head right now and I plan on testing a few combinations.
Even just an anti surge cover and the custom billet wheel on the stock CT26/housing of say the 1hd-t is going to be excellent performance over stock.
I think one of the fancy custom billet wheels/anti surge housing with a turbine upgrade to say a 15B turbine/housing will prove some excellent performance at a very reasonable cost. It would cost more mainly because you would have to source a new turbine an turbine housing over just buying a comp wheel/comp housing.

If someone gets their hands on a functional/complete CT15B from a 1JZGTE, they should give it a try on their 1HDT or 1HZ-T before modifying it. According to some old notes I made, I see that the compressor size of the CT15B from the 1JZGTE is the same as the 1HDFTE at 46/65mm, 50trim. The turbine (as said above) of the CT15B is 48/60mm, 64trim.

Also, just a note, there is a version of the CT20B that has a 48/60mm turbine (opposed to the version with the 50/60mm turbine).
 
the 15B has a different bolt housing in terms of the 1JZ one.
The supra comp wheel is the same dimension as the 15B comp wheel.
So running a 1HD-FTE turbo in comparison to a 1HD or FT turbo would be an upgrade in itself.

If you want even more flow chuck on a 48.3mm/68mm Big 16G wheel will bring on earlier boost.
We already know that this combination works fantastic for low spooling RPM and higher boost pressures (25lbs+)
If your worried about surge thats what the anti-surge housings will be used for:)
 
A bigger OD compressor wheel will generate higher tip speed and more boost. But it will also slow the turbine down a little so the results won't be as dramatic as you expect.
A bigger ID compressor wheel will require more torque to turn and will also slow the turbine so generate slightly less boost.
A smaller turbine will spin up faster, but a bigger turbine will generate more power and spin the compressor harder once it has spooled up.

It's largely about compromise and finding the ones that suit best.

Remember you don't get more flow with bigger turbos. You get more flow with more boost and lower drive pressures. You get the best results when the turbos best efficiency points line up with your target working rpm.
 
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Stock 1hd-t wheel vs the custom big 16g
Apparently it could be .5g lighter after it's minor balancing
 

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