Massive performance with CT26 turbo modified with 65mm Garrett turbine.

[Cañonero]

I was going to write this in Tapage's thread, but this may be a different subject. Anyway, Tapage this may be of your interest.

A guy in the spanish forum working along with his brother that has a turbo workshop, are rebuilding CT26 turbos (that you know have a 40mm turbine), and installing Garret turbines of 55, 60 or 65mm.

The results are being awesome. A guy got 270 HP in his 80 with the 65mm turbo, 3" exhaust, intercooler, new injectors and modified pump.

And the best of all is that he said he achieved that keeping the EGT safe and with a turbo pressure of only 0.8 bar (I think stock is 0.7 bar).

I haven't tested it and haven't got direct relation with them, but that's what they stated. The guy that makes the turbos states that amount of power can be safely achieved in any 1HD-T or 1HD-FT in a good state with this turbo, intercooler and a big exhaust.

In the case of the HDJ100 (1HD-FTE) they think they can easily get 300 HP.


Discussing about this in Lcool, some people think this turbo will improve mid and hig rev performance but will hurt low rev performance. Talking with this guy, he says the biggest improvement is noticiable at low ad mid revs, what I don't understand, as I always heard twin turbo cars have a small turbine to improve low rev. and a big turbine to improve high rev.

Anyway, these are some pictures of the 1HD-T turbo before and after, in this case with the 60mm turbine:

This is the 1HD-FTE version:

 

[racerX]

say Cañonero:

well done - but - I will ask / add - .7 bar seems low for a stock CT26 - as I just pulled one ( Supra donated ) to install on my 3B once I get the larger exhaust - lots of write ups on CT26's -
Assuming one bar = 14.5 -14.7 ( depending on who you ask) psi - careful - i am speaking of a petrol turbine - diesel may be different - Stock Supra and MR2 turbo's are .9 bar - or 13psi - Is not the wastegate the decider - as I am reading guys achieving 1.3- 1.6 bar out of a CT26 with a 60-77mm turbine bored housing on both internal and external wastegate

I wonder now - as I am writing/ thinking - there must be a difference in the CT26's destined for diesel and those for petrol/ and which petrol moteur

I was daydreaming of a CT20B off the MR2 from mid 93-on - this is the dual inlet feed ceramic shaft CT26- supposed to spool fast yet be weakened /fragile even a fraction out of tolerance

cheers:

 

[rideglobally]

wonder how these turbos will perform on a 12ht engine? is it the turbine or compressor wheel that is made bigger?

A guy in the spanish forum working along with his brother that has a turbo workshop, are rebuilding CT26 turbos (that you know have a 40mm turbine), and installing Garret turbines of 55, 60 or 65mm.

The results are being awesome. A guy got 270 HP in his 80 with the 65mm turbo, 3" exhaust, intercooler, new injectors and modified pump.

And the best of all is that he said he achieved that keeping the EGT safe and with a turbo pressure of only 0.8 bar (I think stock is 0.7 bar).

 

[Cañonero]

wonder how these turbos will perform on a 12ht engine? is it the turbine or compressor wheel that is made bigger?

I don't know about the 12ht, but I can ask if you want.


In spanish we say "turbina" so I assumed that it could be translated as turbine. But I would have said that turbina and compressor wheel were the same.

 

[Cañonero]

Some more pictures may help.

 

[Dougal]

The results are being awesome. A guy got 270 HP in his 80 with the 65mm turbo, 3" exhaust, intercooler, new injectors and modified pump.

And the best of all is that he said he achieved that keeping the EGT safe and with a turbo pressure of only 0.8 bar (I think stock is 0.7 bar).

That much power with that little boost is not possible. Especially while keeping EGT's low.

A 270hp 1HD is possible but requires close to 30psi boost at 4000rpm. A turbo with that large a compressor intake will probably not deliver 30psi boost without surging.

 

[rideglobally]

if you can ask that will be great, i almost did this to my turbo, instead we put a compressor wheel that is only 1/16 of an inch bigger because i was not sure of the of the outcome.

I don't know about the 12ht, but I can ask if you want.

 

[blis]

i'd also like to hear how it works on 12ht...

but yeah, im with dougal that much power simply isnt possible with just .8bar...

 

[Cañonero]

I will ask them again about the details of the setup through they got the stated 270 HP, but that's what they said: 270 HP with the 65mm turbo, intercooler, 3" exhaust, new injectors and tweaked pump. That with 0.8 bar and low EGT's.

I agree that's a massive power even with all the above and I also got really surprised about the low turbo pressure. They say that the stock turbo would need twice as much pressure to deliver the same airflow as the 65mm unit, so, according to that, this at 0.8 equals to the standard turbo at 1.6 bar=23.2 psi.

I don't know if that makes sense though.

 

[Dougal]

They say that the stock turbo would need twice as much pressure to deliver the same airflow as the 65mm unit, so, according to that, this at 0.8 equals to the standard turbo at 1.6 bar=23.2 psi.

I don't know if that makes sense though.

Unfortunately for them, that's impossible.

Turbos aren't there to flow air, they compress it so you can fit more into your fixed size engine.
The only way to fit more air into the engine cylinder is to compress it. This requires boost, the more boost you have and the better cooling you have, the more you can fit.

 

[Cañonero]

Thank you Dougal.

I'm considering this and it's very interesting to get opinions on it.

So, appart from the 270HP discussion.... do you think there will be a noticeable improvement with one of these turbos?.

I don't want to get that power in any way, mainly cause it would stress all the transmission, shafts, diffs..... and also cause I don't need that much, I just want to improve engine response, performance and consumption, as I will need a turbo rebuild not to late, this is an option to consider.

 

[Dougal]

Thank you Dougal.

I'm considering this and it's very interesting to get opinions on it.

So, appart from the 270HP discussion.... do you think there will be a noticeable improvement with one of these turbos?.

I don't want to get that power in any way, mainly cause it would stress all the transmission, shafts, diffs..... and also cause I don't need that much, I just want to improve engine response, performance and consumption, as I will need a turbo rebuild not to late, this is an option to consider.

IMO there is no benefit to a turbo compressor that big on a 1HD engine.

I've had a hunt through the garrett catalogs and a compressor with a 65mm inducer is the one used in the GT4088.
It is a terrible match for a 4.2L diesel engine. At 15psi it will be surging until around 2500rpm
Further, it's a compressor capable of 70lb/min, the 1HD engine can't use half of that capacity and the CT26 turbine won't be able to pass that much exhaust either.

Even if you were running 30psi to the rev limit it would be bigger than necessary.

 

[blis]

well, increasing the compressor size while retaining exhaust side.. it will definately change the behavior of turbo but how, no idea... i'd guess it might spool up faster but exhaust pressure would be greater for given pressure...

 

[Tapage]

well, increasing the compressor size while retaining exhaust side.. it will definately change the behavior of turbo but how, no idea... i'd guess it might spool up faster but exhaust pressure would be greater for given pressure...

great thread .. what I like ..

1. 270HP where .. at the wheels .. and how they measure it .. Dyno .. ?

2. I still have the idea of hybrid CT26 with 1HD-T hotside ( to make it simple clear ) and supra 2JZ-GTE cold side .. but now sure if the improvement worth the efford .. ( and money )

3. still valid the concept of keeping the factory 1HD-T CT26 hot side and run a bigger cold side even if you do it swaping a complete new turbo, but just keeping closer to the facotry hot side numbers ..

All it's a compromise .. to get more boost without surging, need bigger cold side, then it will suck at lower rpm .. just that simple ..

With a bigger hot side, hi rpm capable without surging .. iut will suck again at lower rpm .. and If you ask me the 1HD-T need the low end boost ..

 

[Tapage]

Other thing .. it's after good nights reading about, I'm still in the idea of the GT2860R as CT26 upgrade ..

Edit: more search in this topic drive me in to the idea of the T04E compresor wheel to swap in to the CT26 compressor housing .. still thinking in AR housing numbers with the bigger inducer.



I love this game ..

 

[Tapage]

more thoughts ..

Inducer Exducer
TO4E 46Trim 2.00" 2.95"
TO4E 50Trim 2.12" 3.00"
TO4E 54Trim 2.17" 2.95"
TO4E 57Trim 2.23" 2.95"

 

[BreckenridgeCruiser]

Okay, since Dougal (who is the turbo guru here) hasn't chimed in on the behavior of the turbo with that big of a cold side fan, I will try.

Like everything in life, we can only guess (or Dougal can run the numbers) as there are so many variables.

The turbo should spool up faster if it had unlimited exhaust pressure. Put that turbo on a 5.7L engine and it will spool superfast as the exhaust has the power to spin it quickly with the small wheel. It will max out faster however as there is a point where the exhaust airflow cannot add RPMs to the hot side fan due to small surface area.

On the cold side, you have to consider that that fan will add resistance (try driving holding a hankerchief or a bedsheet behind you. Which gives more resistance?). to the turbo spooling. In this case of adding such a mismatched turbine wheel and not changing out the hot side, you will get added resistance and slower spool due to air resistance overpowering the hot side's ability to push hard enough (in the low RPM 1hdt diesel..

Again as Dougal said, if the engine is huge, airflow will matter only in that a bigger intake with bigger cylinders would need more airflow and therfore a bigger turbo to fill it (try filling a bucket with an eyedropper or a hose). Keep in mind though that in this case, pressure would not build with a small turbo on a big engine. So airflow is meaningless if pressure cannot build due to too small of a turbo being used.

I'm not getting inot HP because I like tourque more... It's a real number by measurement and not an equation. Plus I like to test based on my butt in the seat!

HTH.

 

[ledgend80]

well just putting it out there i have just upgraded the ct26 to a gt2871r 56 trim. running 12psi at the moment until my water to air intercooler is fitted then off to get tuned and then maybe 16psi.

 

[lshobie]

There is a guy on the outerlimits board running a 1HZ with some coatings, he has a 1HDT modified pump and runs that engine to 6000 rpm, he has a large turbo on it and runs 18-20 psi IIRC. He has it dyno'd at 235 hp. eats fuel though.

 

[Dougal]

well just putting it out there i have just upgraded the ct26 to a gt2871r 56 trim. running 12psi at the moment until my water to air intercooler is fitted then off to get tuned and then maybe 16psi.

Finally fitted then?

Can you tell me what your minimum rpm is to get 10psi? How does spool compare to the CT26 and which turbine A/R did you get?

*edit*
BTW the 65mm mentioned earlier is the compressor inlet. To put that into perspective your GT2871 in 56 trim has a 53mm inlet.