The 2H/12H-T/1HZ/1HD-T/1HD-FT Gturbo Alternative Tech Thread (4 Viewers)

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No change of tune at all.

I can appreciate a crazy set of headers and a set of compounds and high torque, high horsepower diesels.
I've built a couple of sets of headers and a few exhaust systems over the years. One of which was for my 1hdt and was knocked as ridiculous a few years ago, pretty common now.
I've also contemplated compounds on my HDT in the past.

I've also blown shìt up from ignoring its limits.

None of that excludes me from having an opinion on other things. Take it how you like.

Anyway, knock yourself out, do what you like :meh:

Hmmm interesting change of tune you have going on there @mudgudgeon, you were loving the crazy high hp 1HD builds I was posting a while ago which all make there peak HP at very high RPM (most likely at very max RPM) but now you're carrying like a pork chop over me wanting to pursue my own goals of desired engine performance. :hmm: Once again it seem like the usual case of death by fire squad around here from the usual suspects for anyone sharing thoughts or opinions of their own setups or ways of doing things that differ from the square box they live in.
 
Funny you mentioned fuel economy, it's not something I actively monitor or even care too much about. If I did I certainly wouldn't choose a 4.2L 6cyl to be driving around in. But I have noticed I get about 50km more from my sub tank than with the previous setup by keeping it at higher RPM. There's a lot more going on than just RPM which determines fuel economy.
 
The dyno charts, are they the same car, did you change turbos and diff ratios? The extra load from 3.7’s over 4.1’s will make the pump behave a little differently

I am surprised fuel efficiency isn’t sacrificed with the high rpm turbo .

What are you doing with injection timing advance when running peak power at 4000rpm +. Re piston speed this is very relevant I wouldn’t be ignoring this .

I think if you were aiming for higher hp say 250hp+ you would definitely see fuel economy decrease with majority 3000rpm+ driving compared to a setup that does the same power but delivers most of it below 3000rpm

Myself I prefer a turbo that’s matched to lower rpm peak torque for a daily driver

Always interesting to see different peoples approach to achieving their version of perfection .
 
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I am surprised fuel efficiency isn’t sacrificed with the high rpm turbo

There are very few people who track fuel economy well enough to determine the result of any change. I log every tank and I have seen 10% change in fuel economy from a turbo change. But that was more due to compressor efficiency than the turbo size. Even though the turbine and compressor size changed too.
 
There are very few people who track fuel economy well enough to determine the result of any change. I log every tank and I have seen 10% change in fuel economy from a turbo change. But that was more due to compressor efficiency than the turbo size. Even though the turbine and compressor size changed too.

I do too . Something i picked up from My dad. Even though my driving isn’t even close to a controlled environment I can get a Good idea of average economy.
 
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The dyno charts, are they the same car, did you change turbos and diff ratios? The extra load from 3.7’s over 4.1’s will make the pump behave a little differently

I am surprised fuel efficiency isn’t sacrificed with the high rpm turbo .

What are you doing with injection timing advance when running peak power at 4000rpm +. Re piston speed this is very relevant I wouldn’t be ignoring this .
Yes, those two dynos are the same car. I changed the turbo and diff ratio at same time due to damaged cause from a drunk driver deciding to crash head on into it. Pretty much the whole front end was replaced so I took the opportunity to change the ratio in the diff while it was being rebuilt. Engine luckily wasn't damaged.

I was surprised too but it's not something I really keep track of or really care too much about as it's not my daily. I reset my trip meter each time I fill up so the total km I get for each tank is all I really remember or notice. I just fill it up and enjoy the drive.

I haven't touched the timing yet with this new turbo, still running the same injection timing as before. The timing was set previously by doing time trails using a couple gps/speed apps in fourth gear from 40kph to the speed I made peak boost and the position that set the quickest time was kept. It seems to go well with this turbo down low also and still holds on very well up top but I plan to retest the timing as before but I can't risk randomly driving around at the moment with all this lock down and essential movements only that's going on
 
Yes, those two dynos are the same car. I changed the turbo and diff ratio at same time due to damaged cause from a drunk driver deciding to crash head on into it. Pretty much the whole front end was replaced so I took the opportunity to change the ratio in the diff while it was being rebuilt. Engine luckily wasn't damaged.

I was surprised too but it's not something I really keep track of or really care too much about as it's not my daily. I reset my trip meter each time I fill up so the total km I get for each tank is all I really remember or notice. I just fill it up and enjoy the drive.

I haven't touched the timing yet with this new turbo, still running the same injection timing as before. The timing was set previously by doing time trails using a couple gps/speed apps in fourth gear from 40kph to the speed I made peak boost and the position that set the quickest time was kept. It seems to go well with this turbo down low also and still holds on very well up top but I plan to retest the timing as before but I can't risk randomly driving around at the moment with all this lock down and essential movements only that's going on
Copy, how do the timed runs compare between setups ? Not really a fair comparison but interesting to know still.
With timing I was referring to the timing advance mechanism in the pump, was wondering if you had it mapped to complement the turbo and higher rpm power band .
 
Lol slower obviously but to be fair going from 4.1 to 3.7 ratio diffs is quite a big jump so I kinda need to start all over again with my times for fourth gear pulls. But the longer legs it now has being able to hold third till 120kph and fourth till 180kph suits much nicer. Just a shame I can't give it a real test as all the diesel assaults have been cancelled for the unforseen future. It's ok though always plenty of other stuff to focus on like getting my water/meth system fixed up.

As of yet nothing changed in the auto advance piston but I've been in contact with a company making spacers to give it slightly more range of movement which looks interesting to try but I need to see how the extra RPM goes first and at what stage this becomes a factory causing power to plateau. I'm sure there's a point it'll need to be looked into but currently power is still increasing at a good rate at 4200 so I'm hoping it'll continue to 4800 which I think might be enough for me to be happy.
 
I log every tank and I have seen 10% change in fuel economy from a turbo change. But that was more due to compressor efficiency than the turbo size.
I finale gt my wife convinced that we need a turbo upgrade for the 12ht. But like alway - we are on a tight budget and have around 750€ to spend and not too much shipping costs, so Australia is out go the game ....
I wan't earlier boost and lower EGTs. Basically an Hybrid Ct26 would do the job, but I know that a more efficient turbo might save some fuel to - wich is not super duper important, but would be kinda nice to have since we are upgrading anyway.
Also I would prefer it if it still says CT26 on the housing ;)
I found a compressor housing fron an supra ct26 that I bought a year ago and planed to use that with a supra core/chra and an aftermarket 6cm housing ... is that a solid way to go ?
 
I finale gt my wife convinced that we need a turbo upgrade for the 12ht. But like alway - we are on a tight budget and have around 750€ to spend and not too much shipping costs, so Australia is out go the game ....
I wan't earlier boost and lower EGTs. Basically an Hybrid Ct26 would do the job, but I know that a more efficient turbo might save some fuel to - wich is not super duper important, but would be kinda nice to have since we are upgrading anyway.
Also I would prefer it if it still says CT26 on the housing ;)
I found a compressor housing fron an supra ct26 that I bought a year ago and planed to use that with a supra core/chra and an aftermarket 6cm housing ... is that a solid way to go ?

This is close to what a 1hdfte turbo is, but with the old school turbine wheel. Hdfte turbo had a newer turbine design.

6cm housing will bring boost on earlier for sure, but runs out of legs early too.
I think the older turbine with 6cm housing will be worse for top end turbo efficiency.


As for fuel efficiency, best way to improve it is use less right boot.
 
This is close to what a 1hdfte turbo is, but with the old school turbine wheel. Hdfte turbo had a newer turbine design.
IS there a new turbine design that would fit, or is it better to get an Mamba at that point?
There is no 6cm housing for CT26 unless it's the twin scroll from the 3sgte, otherwise the smallest single scroll is 7cm
True, my mistake. So original is 8cm, optional smaller is 7cm. I guess that would work OK then ?
 
This is a great up to date turbine design which many people I know are running on their CT26 with great success including myself.

THX, so this, a 7cm housing, bigger supra compressor with a billet wheel is "the most" you get from a CT26, without sending it to Munro and others ?

Would this Mamba Kit fit with the supra housing? I'm a bit confused because it says Supra 7mgt and 1hdt ....
 
I finale gt my wife convinced that we need a turbo upgrade for the 12ht. But like alway - we are on a tight budget and have around 750€ to spend and not too much shipping costs, so Australia is out go the game ....
I wan't earlier boost and lower EGTs. Basically an Hybrid Ct26 would do the job, but I know that a more efficient turbo might save some fuel to - wich is not super duper important, but would be kinda nice to have since we are upgrading anyway.
Also I would prefer it if it still says CT26 on the housing ;)
I found a compressor housing fron an supra ct26 that I bought a year ago and planed to use that with a supra core/chra and an aftermarket 6cm housing ... is that a solid way to go ?

A hybrid CT26 won't spool faster or reduce EGT. It will have reduced spool but better top-end.

The only way to get better response and lower EGT without downsides is a more efficient turbine. Luckily the CT26 is an inefficient design and easy to improve on. I'd look for a TD05H based replacement.
 
Trying to work my way thru the 99 pages of this thread, I'm hoping someone can help me narrow down my choice of turbo.

I think i'm leaning toward a Mamba OE style CT26. One of their customer service reps via email pointed me toward these two for a conservative power gain:

https://shop.mambatek.com/TOYOTA-1H...674-GTX2867R-Wheel-001-2427.htm?categoryId=-1

and

https://shop.mambatek.com/TOYOTA-1H...ger-42-65-OE-Wheel-001-2411.htm?categoryId=-1

the only difference I can see is that the 1HZ version uses a compressor with a 49.7/67.4 compressor wheel while the 1HDT flavor uses an "OE" sized 42/65 compressor wheel. Both have the same smaller 1HDT-FTE turbine.

I assume the first one will make more boost at lower RPM?? Anyone think one would be better than the other?

For reference, I have a 70 series, automatic, 4.88's with 34" tires. Im around 2200-2300rpm at 65...ish not looking for radical gains just improving highway driving and the mountain pass drives.
 

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