I was needing an engine to replace the one I managed to kill with water. I was offered a 270,000K 13BT and going to replace the factory Turbo prior to fitting the engine. I've opted for a Kunigawa CT26 60-1. What experience have people had with this particular turbo on a 13BT? I'm not wanting to get into a debate between Turbo brands as I'm sure there is a lot of great options. I specifically want to know real results. My engine is for an Australian Coaster bus and all I'm wanting is a bit more power for them hills not a hot rod. Would be interested in Boost Pressure--Intercooler fitted-or not, exhaust mods.
Turbo choices.
- Thread starter Mr Coaster1990
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mudgudgeon
Resident galah
The turbine housing specs will be the most significant thing that affects how it will perform on a 13BT.
post a link to the specific turbo you have bought?
post a link to the specific turbo you have bought?
- Thread starter
- #3
I'm well aware there's various Turbo options to choose from. This is why I asked specifically about my application. How THIS Turbo(CT26 60-1) performs on a 13BT.
The 60-1 compressor wheel is very very large 60mm inducer / 76mm exducer. It was kinda popular back in the day for the Celica / Supra but didn't stick around long as it would nearly always snap the turbine shaft due to the large loads from the extremely huge comp wheels. It's a bloody huge comp wheel and your driveability is going to suffer with it in your application
- Thread starter
- #5
Thanks or that. I chose that particular Turbo as they claim that it's the "upgraded" version suitable for the 3.4 motor. Fingers crossed it'll do the job with a Dyno tune. it's a bus and it doesn't work overly hard.
mudgudgeon
Resident galah
There's wires crossed here.
60-1 is a reference to the compressor wheel and housing.
CT26 was produced in several variants. Turbine housings vary a lot from one to another.
The *cm2 size of the turbine housing is equally, or more important than the compressor wheel size. Although, both need to work together, and need to be stored to your engine displacement and characteristics.
If you choose a turbo based on compressor specification only, you've thrown away half of the equation or worse.
60-1 is a reference to the compressor wheel and housing.
CT26 was produced in several variants. Turbine housings vary a lot from one to another.
The *cm2 size of the turbine housing is equally, or more important than the compressor wheel size. Although, both need to work together, and need to be stored to your engine displacement and characteristics.
If you choose a turbo based on compressor specification only, you've thrown away half of the equation or worse.
- Thread starter
- #7
So are you able to tell me how this Turbo will perform as a direct replacement for a standard Toyota Turbo. I'm aware of the variations. I'm wanting to know how the CT26 60-1 will perform.
mudgudgeon
Resident galah
No, because you've given us no information in relation to the turbine housing specs
mudgudgeon
Resident galah
Post a link to the turbo you are looking at on the kinugawa site
- Thread starter
- #10
What I'm asking is if there's anyone that has SPECIFICALLY used a KUNIGAWA CT26 60-1 Turbocharger as a direct replacement for a Toyota Turbo on a 13BT.I'm not interested in all the in's and out's of the technical side of things, I'm thinking that's plenty of information. I'll go thru it one more time. I'm after an opinion as to how a KUNIGAWA CT26 60-1 (upgraded to suit a 13BT/14BT)purchased off the internet performs as a direct swap with the factory turbo. It will be Dyno'd . I'm hoping opinions based on actual experience would be better than playing with flow rates etc. It's a bus not a hotrod.
We don't have enough information to identify the turbo you're asking about. You can fix that with a direct link to the Kinugawa turbo you're considering.
mudgudgeon
Resident galah
Good luck then pal.
Enjoy the ride
Enjoy the ride
mudgudgeon
Resident galah
So, you might have no interest in the technical stuff, but you're asking advice from people who can actually give you some useful recommendations, IF you provide them with the technical info.
All you have to do is link a page. You found your way here, can't be that hard to do.
All you have to do is link a page. You found your way here, can't be that hard to do.
No one would use that turbo on a 4.2L let alone a 3.4L so i dont like your chances. I wont give you any details as you dont want that.
Ball bearing Kinugawa Td05-18g on ct20 housing will be better.
FJBen
SILVER Star
Yikes…
I can’t give direct advice to that turbo, but my guess is that its all wrong. The 13bt needs a smaller turbo to run right.
So I’ll give you some advice from my turbo upgrade and how it performs on my 13bt.
As someone who upgraded my turbo I absolutely took the advice of those smarter than me in this subject. I also took the time to learn all math and science tech things so I could understand it. There is a reason no one is running this, because it’s not right for the 13bt.
One of the best matches based on what the engine needs and uses for for air would be a TD04-HL or a Holset HE221w. I bought a new Holset, they are cheap, and for the 5.5cm size since I live at 5000’ altitude. It’s been excellent. Boost instantly and with stock settings I’m easily to 18psi. That turbo is efficient up to 40psi. It’s not a direct bolt on, but it’s damn close.
Most ct26 are not sized right for the 13bt. The ones that are, are usually different vendors and much more money.
I can’t give direct advice to that turbo, but my guess is that its all wrong. The 13bt needs a smaller turbo to run right.
So I’ll give you some advice from my turbo upgrade and how it performs on my 13bt.
As someone who upgraded my turbo I absolutely took the advice of those smarter than me in this subject. I also took the time to learn all math and science tech things so I could understand it. There is a reason no one is running this, because it’s not right for the 13bt.
One of the best matches based on what the engine needs and uses for for air would be a TD04-HL or a Holset HE221w. I bought a new Holset, they are cheap, and for the 5.5cm size since I live at 5000’ altitude. It’s been excellent. Boost instantly and with stock settings I’m easily to 18psi. That turbo is efficient up to 40psi. It’s not a direct bolt on, but it’s damn close.
Most ct26 are not sized right for the 13bt. The ones that are, are usually different vendors and much more money.
FJBen
SILVER Star
- Thread starter
- #18
Thanks for that. I've already purchased this Turbo as it's advertised as a "Bolt On" swap and
"Upgraded " from their previous version. The compressor wheel is 18mm smaller now. I was quite happy with the old 3B till it got drowned so I'm sure I'll be happy with the end result with this engine swap. It's in a bus so torque not speed is required. 110Klms is max speed, it's the hills that slow it down.
Yep that's the one I bought.
mudgudgeon
Resident galah
@Mr Coaster1990
looking at the specs on that, the turbine wheel is the same size as what's used for the 4.2 litre 1HD-T 80 series landcruiser engines.
That's not necessarily a problem by itself because turbine characteristics are also very much dependent on the #cm2 specification on the turbine housing.
This relates to the size of the nozzle that directs exhaust gas into the turbine.
Big cm2 housing equals slow response from the turbo, slow to build boost, but will keep boosting into higher rpm.
A smaller cm2 housing spec means a more focused stream of exhaust gas into the turbine wheel, faster to build boost, more responsive to throttle, but will run out of steam at higher RPM (not gonna be a problem with a 4.2 litre turbo on a 3.4litre engine).
Think of the turbine housing like a garden hose, and the turbine wheel as a BMX bike wheel. If you tighten up the hose nozzle and spray a fine jet of water onto the bicycle spokes at the wheel rim, the wheel will spin fairly easily, and accelerate fast. If you loosen off the nozzle so you have a soft wide stream of water from the nozzle, the wheel takes longer to get spinning, and won't spin as fast.
Now, think of the same garden hose and trying to spin up a big mountain bike wheel. it's not gonna get moving as fast, and won't spin as fast. The greater mass of the big wheel also means it will respond slowly if you increase or reduce flow through the nozzle. This is how an oversized compressor wheel will behave.
If you have the correct size turbine housing (nozzle) to drive a suitable sized turbine, paired with a big compressor wheel, the turbo will push a lot more air at lower boost pressure (good), when and IF you get it spinning fast enough.
In a heavy bus, you want a turbo to respond early and respond fast so you get maximum low end torque. As you said, high RPM high speed output is less relevant to your needs.
An oversized compressor wheel is geared toward high RPM performance right off the bat, and turbine specs become more critical.
Kinugawa haven't listed the cm2 spec for the turbine housing on that turbo, and the casting number on the exhaust housing corresponds with the housing numbers for a 1HD-FTE turbo. This isn't possible. The 1HD-FTE turbine housing and the turbine size they list aren't compatible. Also, the 1HD-FTE housing isn't compatible with the CT26 CHRA (central housing that holds the shaft and bearings).
This is one problem with Kinugawa. They have mixed and matched castings from different turbos to make their own reproductions.
In the past, it was common for them to list turbo specs as "stock" and have them wrong.
Casting numbers often don't match the description.
They also had # cm2 information incorrect for different versions of the CT26, if they published it at all.
This all may not matter if the turbine housing actually is a direct swap for a 13BT housing, but when they haven't published complete specs, you're at the mercy of unreliable or incomplete information.
looking at the specs on that, the turbine wheel is the same size as what's used for the 4.2 litre 1HD-T 80 series landcruiser engines.
That's not necessarily a problem by itself because turbine characteristics are also very much dependent on the #cm2 specification on the turbine housing.
This relates to the size of the nozzle that directs exhaust gas into the turbine.
Big cm2 housing equals slow response from the turbo, slow to build boost, but will keep boosting into higher rpm.
A smaller cm2 housing spec means a more focused stream of exhaust gas into the turbine wheel, faster to build boost, more responsive to throttle, but will run out of steam at higher RPM (not gonna be a problem with a 4.2 litre turbo on a 3.4litre engine).
Think of the turbine housing like a garden hose, and the turbine wheel as a BMX bike wheel. If you tighten up the hose nozzle and spray a fine jet of water onto the bicycle spokes at the wheel rim, the wheel will spin fairly easily, and accelerate fast. If you loosen off the nozzle so you have a soft wide stream of water from the nozzle, the wheel takes longer to get spinning, and won't spin as fast.
Now, think of the same garden hose and trying to spin up a big mountain bike wheel. it's not gonna get moving as fast, and won't spin as fast. The greater mass of the big wheel also means it will respond slowly if you increase or reduce flow through the nozzle. This is how an oversized compressor wheel will behave.
If you have the correct size turbine housing (nozzle) to drive a suitable sized turbine, paired with a big compressor wheel, the turbo will push a lot more air at lower boost pressure (good), when and IF you get it spinning fast enough.
In a heavy bus, you want a turbo to respond early and respond fast so you get maximum low end torque. As you said, high RPM high speed output is less relevant to your needs.
An oversized compressor wheel is geared toward high RPM performance right off the bat, and turbine specs become more critical.
Kinugawa haven't listed the cm2 spec for the turbine housing on that turbo, and the casting number on the exhaust housing corresponds with the housing numbers for a 1HD-FTE turbo. This isn't possible. The 1HD-FTE turbine housing and the turbine size they list aren't compatible. Also, the 1HD-FTE housing isn't compatible with the CT26 CHRA (central housing that holds the shaft and bearings).
This is one problem with Kinugawa. They have mixed and matched castings from different turbos to make their own reproductions.
In the past, it was common for them to list turbo specs as "stock" and have them wrong.
Casting numbers often don't match the description.
They also had # cm2 information incorrect for different versions of the CT26, if they published it at all.
This all may not matter if the turbine housing actually is a direct swap for a 13BT housing, but when they haven't published complete specs, you're at the mercy of unreliable or incomplete information.
- Thread starter
- #20
Thanks for that info. I've absolutely no experience with turbos. I'm hoping it works better than the standard Turbo. I'll get the engine in and see how it drives and if the old motor is good I'll get it Dyno tuned. Fingers crossed it'll work out.
