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Discussion Starter #1 (Edited)
A while ago in this thread I reported some very good dyno numbers on a Caldina 3SGTE transplanted into one of my local customer's Celica. Since then he has upgraded his fuel pump to a Supra MKIV unit and injectors to 84lbs and came back again with the same upgraded CT26 and 100 octane gas and let me have one more go at it to see what it will do. Last time I brought the dyno session to a halt when I felt that the injector duty cycles where getting too close to the limit of what I felt was safe. In this session, we pushed the boost controller as far as it would go and found that the turbo would make no more than just slightly over 18psi no matter how far we turned the dial. I also made a few other little cleanup adjustments to the fuel and timing maps. The final results are:



This is a 4th gear pull, so power is down a little bit from 3rd, but spool can be compared against other turbos.

Seems like this motor and turbo are as happy and strong as can be. The owner reports no problems with the setup other than the fact that 1st and 2nd gear are practically useless on his FWD Celica.

The next step will probably be to upgrade to a bigger turbo.
 

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...my english is terrible Ricky.

but did i read properly , this really done on a upgrated ct26 ?
if so ... WOW ... amazing results.
btw , very nice a/f curve to !
 

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Did they bolt on an older model exhaust manifold and ct26 (is that possible on the Caldina engine?) or is it an upgraded version of the stock Caldina turbo?
 

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How much of a difference do you think that the higher compression makes? Those numbers don't seem a huge deal better than numbers you might see on any gen3 with nemesis, bigger injectors and a race gas tune.
What exhaust and IC is he running?
 

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Discussion Starter #6
Hamster O Death said:
Did they bolt on an older model exhaust manifold and ct26 (is that possible on the Caldina engine?) or is it an upgraded version of the stock Caldina turbo?
The gen3 exhaust manifold bolts right up to the head and from there you can put on any gen3 compatible turbo or turbo it you want.

The stock turbine housing on the Caldina is a one-piece deal that incorporates the exhaust manifold. It is at least a CT20b range turbo. The one on the car right now came from a gen2 motor and has the CT-26 label on the compressor housing.
 

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Discussion Starter #7
mr2by4 said:
What exhaust and IC is he running?
As the previous thread indicates, he is running an A2W PWR IC. The exhaust is a 3" custom job with downpipe. It's a farely quiet one that doesn't turn heads in keeping with the whole sleeper effect of the car.
 

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RickyB said:
As the previous thread indicates, he is running an A2W PWR IC. The exhaust is a 3" custom job with downpipe. It's a farely quiet one that doesn't turn heads in keeping with the whole sleeper effect of the car.
Just wanted to verify. So those numbers are not unbelievable at all. Looks like a very good tune and a nice match of factors. I am just curious how boost compares to compression. Looks like you are making #s at 18psi that are comparable to mine at 20psi but I am running lower compression.
It makes an interesting point of comparison for those evaluating factors when building motors.
 

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Do you think that the clip on the turbine wheel made alot of difference? There are lots of people with simply upgraded compressors not making near this power, and then when the turbine is clipped a little it suddenly seems to flow alot more :eek: .
 

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Tomg said:
So is this the first ct26 that has passed 300whp?

T
Nope
I hit 320rwhp on an ATS ct26 a couple of weeks ago. Look for me just above No Shoes on the dyno registry.
 

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Discussion Starter #14
Po' Kid said:
That really makes me want to try having the turbine wheel clipped. Awesome results!
Thank you.

I don't really recommend this upgrade in general. The compressor wheel is far too big for the job it needs to do. It just reduces transient response while adding just a little top end at best. The turbine clip made sense before rebuilds that increased the turbine nozzle area (the CT27) came along, but they increase peak flow by decreasing turbine efficiency which again leads to reduced transient response. This turbo was used by the owner just because it was on the shelf from a previous failed motor (when he was still playing around with black boxes to try to make power).
 

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RickyB said:
Thank you.

I don't really recommend this upgrade in general. The compressor wheel is far too big for the job it needs to do. It just reduces transient response while adding just a little top end at best. The turbine clip made sense before rebuilds that increased the turbine nozzle area (the CT27) came along, but they increase peak flow by decreasing turbine efficiency which again leads to reduced transient response. This turbo was used by the owner just because it was on the shelf from a previous failed motor (when he was still playing around with black boxes to try to make power).
Yeah I understand the downfalls of clipping the turbine wheel vs upgrading / modding the hotside. I was just thinking that if it only costs like 100 more or something like that, why not have it done on an otherwise stock turbo when you send it in for a standard rebuild? From what I understand, the stock compressor wheel is capable of at least 15 PSI to redline, but the stock turbine housing cant flow enough gases through it to keep the shaft speed up. So I was just thinking, that if the turbine wheel can be clipped for like 100 extra, then why not sacrifice a little spool for what, like 30+ more RWHP?

Although, of course, once you get into that, you can spend a few hundred more and get a CT20b or CT27 and be done with it.
 

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Discussion Starter #16
mr2by4 said:
Nope
I hit 320rwhp on an ATS ct26 a couple of weeks ago. Look for me just above No Shoes on the dyno registry.
You are talking about a CT27, which is a different beast because it has the turbine housing machined for more flow. Technically, it starts as a CT26, so it is a "rebuilt" CT26, however if we follow the historical lineage of stock turbo upgrades, the CT27 isn't considered a simple CT26 upgrade and has become a different species. This is probably why you don't see why this particular result is a bit of a landmark in 3SGTE history.
 

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Discussion Starter #17
Po' Kid said:
Do you think that the clip on the turbine wheel made alot of difference? There are lots of people with simply upgraded compressors not making near this power, and then when the turbine is clipped a little it suddenly seems to flow alot more :eek: .
Woa, this is shades of the never ending debates of 3 years ago :)

Clipping was at one time the only option available to those wishing to upgrade their CT26. Clipping increases flow at the cost of reducing the efficiency of the turbine wheel. Clips of as high as 12-15 degrees were tried and there was always some increase in flow along with a decrease in spool.

The CT27 made clipping obsolete in the upgrade market as it addresses the problem of increasing turbine flow much more comprehensively than a clip does. By remanufacturing the turbine housing to allow more flow and upgrading the turbine wheel in addition to the compressor wheel, you effectively produce a new turbo that just happens to still use the same CHRA and mounting flanges but is internally engineered to be more efficient than any CT26, clipped or otherwise, could hope to be.
 

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Discussion Starter #19
Tomg said:
So this is a ct27?
No. This car is running a CT-26 with a 60-1 compressor wheel and a clipped turbine wheel. mr2by4 is the one who has a CT27.
 

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It would be interesting to see what the car could do if he puchased the modified exhaust housing from ATS. The the backpressure reduced, I'd think he'd be able to increase the psi a lot more. He'd probably have a 350whp car on hand. Spool would slow down just a tad more, but probably no more than 150rpm.

On the other hand, if he switched over to the Supra housing...I'd bet he'd have a 370+whp car on hand.

Man I love to speculate. Somebody please prove me right or wrong.
 
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