CT26 VNT upgrade/ modification (1 Viewer)

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Hi Guys

I'm just wondering if it is possible to upgrade and modify the CT26 VN turbo by boring out the housing and putting a bigger mechanical wheel/ turbine in there and by getting rid of the electronics since the turbo is going on a mechanical fuel injected motor that doesn't have an ECU?

Has anyone rendered the CT26 VNT a non-VNT before? Can it be done? If, so what's needed and more or less how much would it cost?

Thanks
 
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Back the bus up a little bit. Do you have an engine or just the turbo? Are you after more boost, do you think you're at the limit of the current turbo?
 
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Thanks for the replies guys, but I decided to just swap the whole CT26 with a Garrett 2860R. The CT26 is off a 1KD-FTV, and will be going on sale in a couple months.
 

Tapage

Club 4X4 Panamá
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those new KD are using VNT CT 26 .. ? what a surprise ..
 
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I have quite a few turbos sitting in my workshop. I do alot of turbo high flows.

Just so happens that one of them is the 1KD-FTV turbo and it is not a CT26. It is a turbo (three bolt flange with 30010 stamped on the exhaust housing) made under licence by IHI. It has a 39/58 compressor wheel and a 51/48mm exducer turbine. I am planning a high flow mod for these turbos as we speak. It is not a good size for a 4litre + engine and in my opinion is a bit smaller than it needs to be on the cold end for a 3L.

I also have a turbo from the single turbo 1VD V8 engine. Interestingly it is a Garrett GT2359V with vacuum controlled vanes made for toyota (50010 on exhaust housing). It has a 44.5/59.5 comp wheel and a 52/47 turbine. In my opinion it is inferior to the IHI unit.

I have a modified CT26 turbo that really does a great job and you wont want the hassel of any of the small VNT's. A 4L diesel really is big enough to mitigate many of the benefits of the VNT. But for big torque in the 1000-1600rpm range, nothing will beat the VNT. I plan to try a modified 1KD turbo later with a home made VNT controller - see how I go time wise....... I think it would make a great primary in a compound setup.

I send off one of the new CT26 turbos today and one tomorrow. 1 is going on a 1HDT and the other is going on a 12HT. So, hopefully some great independant feedback on this mod. I am really excited to hear the feedback. So if you are interested in solid low end performance and good outright power, watch the threads.
 
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Thanks for that info Graeme, I've been meaning for a long time to find out what the low power V8's were using.
 
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Those small frame Garrett VNT's are almost disposable.... They are made in such a way that any amount of water travelling, probably even normal use really, especially if any salt is involved, means that the exhaust housing and CHRA are friends for life. It was all I could do not to detroy the turbo when pulling it down. Thankfully it is OK and I will be liberasl with the anti sieze on the flange after I high flow it. On the V8 they sit right down the bottom next to the sump.

Thanks for that info Graeme, I've been meaning for a long time to find out what the low power V8's were using.
 
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The next turbo I'll be looking for is a low mount 1749v or similar for my 2.2 diesel work car. Let me know if you trip over any.:cheers:
 
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Hi Dougal, DI or IDI?

I could probably get one.... I dont really go that small..... eBay best here as I deal with 4wd's mostly. I do some petrols that use the CT26 such as GT4 and MR2 but not much else.

You are just talking VW1.9TDi size arent you?
 
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Yeah di. VW turbo would be great if they weren't integrated into the manifold and could have the actuator not foul an exhaust manifold above.
It's a nissan YD22, smaller brother to the YD25 in the navaras. Factory turbo in europe is a GT1849V on the commonrail versions and a 1549 wastegated on the rotary pump ones.
Interestingly the 110kw YD25 in the vans use a GT1749V. But they're torque limited to 280Nm due to the gearbox they're bolted to.

I'm thinking of throwing a T25 on it when I get around to it. Figure out fuelling and VNT control later.
 
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I just found out that the reason for this thread was due to changing the CR 1KD-FTV engine to mechanical inj and wastegated. A GT28060R is way too big for low end power, I wouldnt expect decent boost before 2200rpm and probably have to overfuel to get there. The one I had experience with was on and intercooled TD42. It made 201hp@ wheels @ 3200rpm but surged like anything below 1800rpm from ~ 16psi up and smoked a heap to get it to spool too. 0.64 ex housing. Personally after the experience with both BB and non BB versions of the GT2860R, I would steer clear of them and get a TD05H 16G small with 6cm housing or a modded CT26 (or even a stock one with Supra comp wheel and std 58010 exh housing) any day.

Anyway, be interesting to find out how it all works - huge project and I cant think of a good reason to get rid of the CR unless it is going to be a highly remote location truck. Even then you have to question custom mechanical vs factory CR for reliability. In any case, it is a very interesting project and one I would like to hear the results of,
 
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I might be able to get a stuffed one from a YD25.... or even the ZD30 - which is even smaller than the YD25 (128kw version of YD25)

You might be better off looking in NZ as freight is a killer unless it is of high value. :cheers:

Yeah di. VW turbo would be great if they weren't integrated into the manifold and could have the actuator not foul an exhaust manifold above.
It's a nissan YD22, smaller brother to the YD25 in the navaras. Factory turbo in europe is a GT1849V on the commonrail versions and a 1549 wastegated on the rotary pump ones.
Interestingly the 110kw YD25 in the vans use a GT1749V. But they're torque limited to 280Nm due to the gearbox they're bolted to.

I'm thinking of throwing a T25 on it when I get around to it. Figure out fuelling and VNT control later.
 
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Its a flutters out the intake at relatively low frequency (say 5-10Hz) and it is caused by the stalling of the comp wheel. The GT2860R(S) are notorious for it when pushed for performance. The turbo died before it got to 5000kms. It was a brand new $1700 genuine BB garrett. The bearings failed due to surge, Actually side play was fine but it had 1mm of end play !!!

It was running 25psi. Was really nice from 2200rpm to 3500rpm, Also seemed to behave badly when stabbing the throttle at high rpm - say if your already at 3000rpm or so without much load and you stabbed it, it seemed to choke and would not get full boost (small turbine I am guessing caused backpressure when stabbing it and opened the wategate). Its just a theory and we couldnt solve it. Now the truck runs alot more fuel, doesnt smoke above 2200rpm, revs sweetly to 5300rpm and makes over 280hp @ wheels :)
 
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A mate of mine had a GT2860 die in similar i believe circumstances on a TD42 running ~25psi

5300rpm is nice in a big 6 diesel, 13BT wont go past 3600rpm (which is more than enough, it vibrates just a little :steer:)
 
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A mate of mine had a GT2860 die in similar i believe circumstances on a TD42 running ~25psi

5300rpm is nice in a big 6 diesel, 13BT wont go past 3600rpm (which is more than enough, it vibrates just a little :steer:)
Thats interesting. A local diesel perfromance shop wont put them on any more for this reason. But people still try them - like they also try GT2540's.....:rolleyes:

Look, they are an extremely efficient turbo, but unless you have full electronic control of boost and fuel, you cant keep them out of low end surge AND have a tough 1800-2200rpm band, it just doesnt work - no matter how hard you try with the aneroid boost/fuel profile.

A GT2871 would be better because it stands a better chance of keeping from surge, but it is still all wrong as even the smallest trim 71 compressor (48) is a bit on the big side.
 
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Yet still on forums worldwide the GT2860R (and worse the disco potato) keeps being recommended for high boost diesels. Even for diesels as small as 2.5 and people try to crank 25psi out of them.
 
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Even though this is all a little off topic, still good info!

Which is probably why most of my mates run GT2871/76's now, they all seem to be running ok still, even the one on a comp truck rushing past 30psi on a TD42.

I drove a 1HZ with a GT2876 last weekend, about 14psi, it was nice to drive, the motor was willing to rev and so smooth compared to mine. I didnt take much notice on how it built boost though, small tyres got it up in the rpm quickly.
 
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Hi guys. Thanks for all the replies. very useful information. So on the Garrett website, they list five GT2860's. Which one of these are you guys referring to, or are they all bad?

GT2860R - 707160-5
GT2860R - 707160-7
GT2860R - 739548-9
GT2860RS - 739548-1
GT2860RS - 739548-5

TurboByGarrett.com - Turbochargers
 

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