No downside. It's slightly better than running a log style manifold.
The 2H/12H-T/1HZ/1HD-T/1HD-FT Gturbo Alternative Tech Thread
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No downside. It's slightly better than running a log style manifold.
Mamba TD05-18g install on 1HDT 
I will go thru the install of a Mamba TD05-18g on my 1992 Landcruiser HDJ81V. This is my first diesel and first 4x4 so it has been interesting. I am a journeyman motorcycle and certified marine mechanic. I also have a fascination with 2 stroke engines as well.
The main focus was not outright horse power but an engine with the manners of a stocker with a boost in power to pull a trailer or quickly pass another vehicle on the hiway. Fuel economy needs to be maintained as well.
There were a number of things that I did at once to the engine...
1- New Mamba TD05-18g turbo with 11 blade billet GTX style compressor wheel with extended tips. The hot side has a 9 blade STS style turbine.
2- rering and hone engine, grind valves and do a performance valve job. 5 angle valve seat on intake and 3 angle on exhaust.
3- ported the head. Intake ports are pretty large so they received cleanup. The exhaust port was enlarged about 3 mm. The valve pockets on both intake and exhaust were modified heavily. The short side radius is very tight on the exhaust.
4- fabricated intercooler with dual outlets. Top mount.
5- modify intake manifold with dual inlets in an attempt to balance flow.
6- modify air cleaner system for better flow. Adding second filter.
7- rebuilt injectors and pump. slightly modded to match turbo
I will focus on the turbo install here.
The exhaust housing bolts to the stock manifold and exhaust. The turbo was not clocked to fit the 1HDT out of the box in fact the bolts were loose on the exhaust housing. Clocking was not an issue to resolve but if you expect out of the box bolt on fitment this was not the case. Also the waste gate actuator was not lining up properly. I emailed pics to taiwan and Mamba replied promptly that I was shipped the wrong bracket and rod. They shipped a new one from taiwan and it arrived in 5 days.
With turbo now mounted and actuator lined up I attempted to install the supplied coolant lines. The AN style fittings and hoses are next to impossible to make work. The downward facing line would be possible to use but the nature of the AN fitting causes minor interference with the motor mount. The upward facing line would be one step away from being kinked as it points directly at the manifold. Even without the heat shield it is very close. I found it unacceptable to use either hose or fittings and opted to make my own steel lines. The blue lines are what I fabed up from some used lines. Very similar lines are available from Mamba,s catalogue. I emailed them with the issue of the coolant lines 2 times and did not get a response back...pics included. Again the work around was not difficult but to have the supplied lines that fit the advertised "fit 1HDT" would have simplified things.
The turbo intake is smaller than the stock CT26. I simply cut a silicone hose to coil inside the standard intake tube and glued it in.
The turbo oil drain hose spigot is smaller than stock. I found a piece of hose that fit over the turbo drain and into the stock drain hose.
So at the end of the day I am satisfied so far. Turbo comes on about the same as a stock CT26, currently running 18 psi and the power increase is very good. Nice driveability without tuning the fuel yet. EGT,s barely break 1000F under full load.
Once the air filter is modded then boost goes to 24psi i am sure with some tuning things will be awesome.
View attachment IMG_1014.JPG
View attachment IMG_1029.JPG
I will go thru the install of a Mamba TD05-18g on my 1992 Landcruiser HDJ81V. This is my first diesel and first 4x4 so it has been interesting. I am a journeyman motorcycle and certified marine mechanic. I also have a fascination with 2 stroke engines as well.
The main focus was not outright horse power but an engine with the manners of a stocker with a boost in power to pull a trailer or quickly pass another vehicle on the hiway. Fuel economy needs to be maintained as well.
There were a number of things that I did at once to the engine...
1- New Mamba TD05-18g turbo with 11 blade billet GTX style compressor wheel with extended tips. The hot side has a 9 blade STS style turbine.
2- rering and hone engine, grind valves and do a performance valve job. 5 angle valve seat on intake and 3 angle on exhaust.
3- ported the head. Intake ports are pretty large so they received cleanup. The exhaust port was enlarged about 3 mm. The valve pockets on both intake and exhaust were modified heavily. The short side radius is very tight on the exhaust.
4- fabricated intercooler with dual outlets. Top mount.
5- modify intake manifold with dual inlets in an attempt to balance flow.
6- modify air cleaner system for better flow. Adding second filter.
7- rebuilt injectors and pump. slightly modded to match turbo
I will focus on the turbo install here.
The exhaust housing bolts to the stock manifold and exhaust. The turbo was not clocked to fit the 1HDT out of the box in fact the bolts were loose on the exhaust housing. Clocking was not an issue to resolve but if you expect out of the box bolt on fitment this was not the case. Also the waste gate actuator was not lining up properly. I emailed pics to taiwan and Mamba replied promptly that I was shipped the wrong bracket and rod. They shipped a new one from taiwan and it arrived in 5 days.
With turbo now mounted and actuator lined up I attempted to install the supplied coolant lines. The AN style fittings and hoses are next to impossible to make work. The downward facing line would be possible to use but the nature of the AN fitting causes minor interference with the motor mount. The upward facing line would be one step away from being kinked as it points directly at the manifold. Even without the heat shield it is very close. I found it unacceptable to use either hose or fittings and opted to make my own steel lines. The blue lines are what I fabed up from some used lines. Very similar lines are available from Mamba,s catalogue. I emailed them with the issue of the coolant lines 2 times and did not get a response back...pics included. Again the work around was not difficult but to have the supplied lines that fit the advertised "fit 1HDT" would have simplified things.
The turbo intake is smaller than the stock CT26. I simply cut a silicone hose to coil inside the standard intake tube and glued it in.
The turbo oil drain hose spigot is smaller than stock. I found a piece of hose that fit over the turbo drain and into the stock drain hose.
So at the end of the day I am satisfied so far. Turbo comes on about the same as a stock CT26, currently running 18 psi and the power increase is very good. Nice driveability without tuning the fuel yet. EGT,s barely break 1000F under full load.
Once the air filter is modded then boost goes to 24psi i am sure with some tuning things will be awesome.
View attachment IMG_1014.JPG
View attachment IMG_1029.JPG
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Mamba TD05-18g install on 1HDT
I will go thru the install of a Mamba TD05-18g on my 1992 Landcruiser HDJ81V. This is my first diesel and first 4x4 so it has been interesting. I am a journeyman motorcycle and certified marine mechanic. I also have a fascination with 2 stroke engines as well.
The main focus was not outright horse power but an engine with the manners of a stocker with a boost in power to pull a trailer or quickly pass another vehicle on the hiway. Fuel economy needs to be maintained as well.
There were a number of things that I did at once to the engine...
1- New Mamba TD05-18g turbo with 11 blade billet GTX style compressor wheel with extended tips. The hot side has a 9 blade STS style turbine.
2- rering and hone engine, grind valves and do a performance valve job. 5 angle valve seat on intake and 3 angle on exhaust.
3- ported the head. Intake ports are pretty large so they received cleanup. The exhaust port was enlarged about 3 mm. The valve pockets on both intake and exhaust were modified heavily. The short side radius is very tight on the exhaust.
4- fabricated intercooler with dual outlets. Top mount.
5- modify intake manifold with dual inlets in an attempt to balance flow.
6- modify air cleaner system for better flow. Adding second filter.
7- rebuilt injectors and pump. slightly modded to match turbo
I will focus on the turbo install here.
The exhaust housing bolts to the stock manifold and exhaust. The turbo was not clocked to fit the 1HDT out of the box in fact the bolts were loose on the exhaust housing. Clocking was not an issue to resolve but if you expect out of the box bolt on fitment this was not the case. Also the waste gate actuator was not lining up properly. I emailed pics to taiwan and Mamba replied promptly that I was shipped the wrong bracket and rod. They shipped a new one from taiwan and it arrived in 5 days.
With turbo now mounted and actuator lined up I attempted to install the supplied coolant lines. The AN style fittings and hoses are next to impossible to make work. The downward facing line would be possible to use but the nature of the AN fitting causes minor interference with the motor mount. The upward facing line would be one step away from being kinked as it points directly at the manifold. Even without the heat shield it is very close. I found it unacceptable to use either hose or fittings and opted to make my own steel lines. The blue lines are what I fabed up from some used lines. Very similar lines are available from Mamba,s catalogue. I emailed them with the issue of the coolant lines 2 times and did not get a response back...pics included. Again the work around was not difficult but to have the supplied lines that fit the advertised "fit 1HDT" would have simplified things.
The turbo intake is smaller than the stock CT26. I simply cut a silicone hose to coil inside the standard intake tube and glued it in.
The turbo oil drain hose spigot is smaller than stock. I found a piece of hose that fit over the turbo drain and into the stock drain hose.
So at the end of the day I am satisfied so far. Turbo comes on about the same as a stock CT26, currently running 18 psi and the power increase is very good. Nice driveability without tuning the fuel yet. EGT,s barely break 1000F under full load.
Once the air filter is modded then boost goes to 24psi i am sure with some tuning things will be awesome.
View attachment 1406227
View attachment 1406311
View attachment 1406320
View attachment 1406323
View attachment 1406324
Here are a few more pics. One pic is of the supplied coolant hose interfering with the exhaust manifold. Another is the oil drain hose mod. Had to grind the slotted hole slightly to mount the replacement actuator bracket. And a few misc pics.
On another note Mamba supplied a chart to set the waste gate actuator preload. After attempting to set the preload to match there specs I could not get the travel of the actuator rod to match there specs. I tried 2 different supplied springs. So I ended up using the 22 psi spring with there specs for 1mm and 5mm but I could not get 8mm or 10mm of travel because the actuator was bottomed out. I contacted them several times with this situation too and got links to faqs that were not helpful. Once up and running the 22 psi spring with preload adjusted to there 1mm and 5mm spec gave 15psi of boost.
P.S. my truck runs very well the Mamba turbo set to 18 psi on a manual boost controller.
View attachment IMG_1030.JPG
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You said you haven't tuned the fuel yet, what afrs are you running?
I'm dying. You're killing me
You didn't hear? This has just turned into the "you should probably just buy a Gturbo" threadI'm dying. You're killing me
Let's see her on the dyno! Thanks for posting this.
I used to agree with that, until my personal experience with gturbo left a lot to be desired, both in performance and service
Quick preview of prototype, 3rd gear from 1400rpm to 35psi
I Dont have an AFR guage yet. All I can tell you is there is a little puff of smoke from idle if you depress the throttle quickly. Decent responce off boost then starts spooling about 1600rpm making 15 psi by 1800 rpm boost builds very fast to 18 psi my current set point. No smoke at all once it is above idle. What is the best AFR guage for a diesel?
I use innovate gauges, both the MTX-L and the LM-2 standalone. Both are as accurate as the sensors on a dyno, I've checked them against both mainline and dyno dynamics machines, within 0.1 of each other
Not even close. But if anyone thinks they can cook up a fantastic VNT solution at home. I welcome them to try.
Nice gauges Rob. Is your turbo running a standard ct26 turbine or have you found a higher flowing one? I never had any luck with ct26 turbines other than the standard form. Running boost like that mate you must be interested in a compound set up? Your engine bay would need to loose the stock manifold for a custom one to fit it though, but I'm pretty sure there is physically enough room in there though. There are compound I have planned to do for my Isuzu and kowalskis truck based on Dougals design that would work fairly well on a 1hdt. Id post it up but it's his baby, that and Absalom is so anoying it sort of erases my desire to post anything meaningful.
Do the same in 4th man
This tuned yet?
Boost Response looks pretty similar to a td06
How's it feel to drive, smooth and strong once on boost
I'm succeeding then. But in all seriousness, you shouldn't let yourself be so easily affected by what complete strangers post on the internet..
This is pretty childish. Can't you kids quit the bickering? I've been lurking in this thread a long time and kept my mouth shut, but several people have been pretty cold to others who have come in late with differing views and/or technical experience.
I'm not just directing my comments at you. Keep this thread tech, this isn't highschool.
What turbo and mods are you running?
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I apologize in advance for the role I've played.
Rob, thanks for the video! Would love to see a longer clip
Rob, thanks for the video! Would love to see a longer clip
Haha that was on the way to work the other night, to do a 4th gear run I would need to get out of a 60 zone
But yeah, good response, smooth and seems to flow well. I don't want to jump to any conclusions vs the gturbo until I get on the dyno though
