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Conrad_Turbo
02-17-2005, 02:18 PM
So I am doing some work to a few CT26's in my shop and I had a chance to compare it to the nearest Mitsubishi variant, the TD05H-14B or it could possibly be the 14G. I am no expert in the Mitsu camp, but the 14B or 14G comes off the 1st generation (1G) DSM. The engine the turbo resides on has a displacement of 2.0L, but it's just amazing the difference of the turbine/turbine shaft design. I know there is a lot more to a turbo than just the turbine...but the CT26 looks like a monster to the Mitsu turbo. I wonder if the Mitsu crowd gripes and complains about their stock turbo as much as we do about the CT26? Haha.

Here are two pics comparing the two (dirty CT26 on the left and blasted mockup Mitsu on the right).

http://img.photobucket.com/albums/v622/mixman1982/189_8909.jpg
http://img.photobucket.com/albums/v622/mixman1982/189_8910.jpg

Here is the compressor map for the 14B and 14G (quite similar). Anyone know exactly what the 14B and the 14G reside on?

http://www.stealth316.com/images/td05-14b-raw.gif
http://www.stealth316.com/images/td05-14g-raw.gif

It's interesting noticing the differences between different company turbo design. The reason for all this research is that I will be building the TD05-CT26 adapter to allow for more options for 3sgte owners with turbo selection. I just want to learn as much as I can about the Mitsu camp and see how their equipment work with their engines. Also does anyone have the compressor map for the CT26 kicking around?

PerSonalHell
02-17-2005, 02:36 PM
I know that a lot of the dsm guys use the 14b as a upgrade for the t25, and some are running 11's on the stock turbo.

BTW - the pics don't work for me.

nuclearhappines
02-17-2005, 05:14 PM
see people never believe me when i tell them the CT-26 is HUGE. and it is ...

You can fit a T3 60 trim in the CT-26 housing... it's a big factory turbo....

anyway, there are alot of Mitsu turbos, some have the different height blades like the CT-26 ...supposedly the 13G does, but the 13C doesn't ...and apparenlty the B series doesn't either by looking at your design.

Another thing i hear commonly about the 14b is that it's not the greatest flowing turbo but it's power comes from its balance ... ie in the choice of intake/exhaust side combination.

edit : the last thing i want to say is , the toyota camp does not have dataloggers, and except for the crazy supra owners, most toyota owners are either daily driving / double dutying their cars or just plain afraid of what happens after 15psi ...which is why people will go and put a 60 trim in a CT-26 and then 'only' see a 20hp gain (sure at 15psi that what it gains) ... i'm sure such turbos (like the one clayton has on his car) ... can make more power... it's just that people don't like to go there

-nuke

Trance4c
02-17-2005, 05:57 PM
see people never believe me when i tell them the CT-26 is HUGE. and it is ...

You can fit a T3 60 trim in the CT-26 housing... it's a big factory turbo....

anyway, there are alot of Mitsu turbos, some have the different height blades like the CT-26 ...supposedly the 13G does, but the 13C doesn't ...and apparenlty the B series doesn't either by looking at your design.

Another thing i hear commonly about the 14b is that it's not the greatest flowing turbo but it's power comes from its balance ... ie in the choice of intake/exhaust side combination.

edit : the last thing i want to say is , the toyota camp does not have dataloggers, and except for the crazy supra owners, most toyota owners are either daily driving / double dutying their cars or just plain afraid of what happens after 15psi ...which is why people will go and put a 60 trim in a CT-26 and then 'only' see a 20hp gain (sure at 15psi that what it gains) ... i'm sure such turbos (like the one clayton has on his car) ... can make more power... it's just that people don't like to go there

-nuke


I would like to go there.. trust me. But I am all to aware that I do not have the fuel for it. At this point, I realize that I am underpowering this turbo by a LOT!

Conrad_Turbo
02-17-2005, 06:40 PM
Ya the turbo is a monster, I always knew it was large...but damn having it next to a Mitsu turbo that is sized for the same displacement makes you wonder why we gripe about the CT26 so much. I know the turbine isn't the end all to turbo performance, the housing has a lot to do with it as well...but having them side by side puts a good perspective on the sheer size difference.

After a bit more research I found a few more things that should clarify some confusion of mine.

'90-94 Auto Transmission DSM - 195hp stock?
TD04-13G-5cm^2

'90-94 Manual Transmission DSM - 195hp stock
TD05-14B-6cm^2

'95-99 DSM - 210hp stock
T25

Starion/Conquest
TD05-14G-8cm^2

Luni
02-17-2005, 06:57 PM
Wow.. Interesting info Conrad.

Im wondering what a 16G would do for us.. The MR2 guys seem to think its a kickass turbo for a dsm but on a 3SGTE it isnt that great. IT doesnt make sense to me if thats the case. What makes their engines so much more efficient than ours?

Conrad_Turbo
02-17-2005, 07:45 PM
The only major difference I see on a 1st generation DSM is the fact that they have mucher lower compresson ratio than us, which would allow them to run more boost. So I'd say the Mitsu turbo has the greatest efficiency range in a higher PR than the CT26. All this is just speculation on my part...but it is quite interesting comparing the two. At this moment I am not sure why the 14B or 16G turbo wouldn't work well on a 3S-GTE, unless the 3s wasn't going to run higher than stock boost levels.

I just want to find out the faults of the CT26 and find out exactly why it starts to fall on it's face after 15psi, then see where the CT26 can be tweaked and made better...or even replace it with a low cost substitute that outperforms it altogether.

Trance4c
02-17-2005, 11:14 PM
The only major difference I see on a 1st generation DSM is the fact that they have mucher lower compresson ratio than us, which would allow them to run more boost. So I'd say the Mitsu turbo has the greatest efficiency range in a higher PR than the CT26. All this is just speculation on my part...but it is quite interesting comparing the two. At this moment I am not sure why the 14B or 16G turbo wouldn't work well on a 3S-GTE, unless the 3s wasn't going to run higher than stock boost levels.

I just want to find out the faults of the CT26 and find out exactly why it starts to fall on it's face after 15psi, then see where the CT26 can be tweaked and made better...or even replace it with a low cost substitute that outperforms it altogether.

Its all in the exhaust turbine man. As you said beofre, the mitsu turbo is well balanced. The CT26 is not in that case. In my case, with a 60-1 intake compressor.. its HUGE compared to my exhaust turbine. But at this point its not efficent at all for the low psi I'm running. Take a look into the work thats been done by ATS Racing on their CT27 varient, its all work on the exhaust housing/turbine.

Luni
02-17-2005, 11:47 PM
That doesnt make sense tho Conrad.

If their CR is lower that means they dont gain as much power per hp as we do. And they run around the same type of boost we do - right around 15-17 psi on a stock engine (they have to rewire their fuel pumps) but it seems they are making more power per psi almost.. Its like they have a lower CR AND a higher VE or some crap.

Cause it makes no sense to me.. Theres TONS of DSMs on the 14b making 12 second passes making 300 hp and not a whole lot of toyota guys doing it.

You knwo what, Im with nuke. I think the 3SGTE people are just stuck on shit and afraid to try new shit out of the box. He has been talking to me about an AFM swap and nobody seems to want to investigate it. EVERYONE else out there can do it, supras, lexus, vettes, etc they all dick around with their AFM/injector combos with good results. Nobody seems to have to balls in the celica/mr2 world to do it. It just disgruntles me. Its like we have this kickass car and nobody knows how it really works, its like for all of our info we cant figure shit out..

sorry, disgruntled. My car doesnt work, fighting my fuckin battery light, just spent a bunch of money on it, etc. Im not feelin so hot about the whole thing right now.

Trance4c
02-18-2005, 12:09 AM
That doesnt make sense tho Conrad.

If their CR is lower that means they dont gain as much power per hp as we do. And they run around the same type of boost we do - right around 15-17 psi on a stock engine (they have to rewire their fuel pumps) but it seems they are making more power per psi almost.. Its like they have a lower CR AND a higher VE or some crap.

Cause it makes no sense to me.. Theres TONS of DSMs on the 14b making 12 second passes making 300 hp and not a whole lot of toyota guys doing it.

You knwo what, Im with nuke. I think the 3SGTE people are just stuck on shit and afraid to try new shit out of the box. He has been talking to me about an AFM swap and nobody seems to want to investigate it. EVERYONE else out there can do it, supras, lexus, vettes, etc they all dick around with their AFM/injector combos with good results. Nobody seems to have to balls in the celica/mr2 world to do it. It just disgruntles me. Its like we have this kickass car and nobody knows how it really works, its like for all of our info we cant figure shit out..

sorry, disgruntled. My car doesnt work, fighting my fuckin battery light, just spent a bunch of money on it, etc. Im not feelin so hot about the whole thing right now.

I want an AFM swap :(

Blackcloud
02-18-2005, 12:32 AM
I still wish i had a turbo

Lagos
02-18-2005, 12:48 AM
all i know is that i showed off my swap to a bunch of DSM guys i know. they where all shocked and amazed at the size of my stock turbo!

Lagos
02-18-2005, 01:07 AM
oh, and about this "being afraid to try new things". you have to remember something that a lot of people seem to forget. most of us here didnt start out with a turbo celica from the factory. it took a lot of work, time, and money to get to run 10-15psi daliy. so, we are not just going to experiment on our motors unless why know that its 100% safe.

the other thing to remember is that dsm guys do dumb things all the time. i know guys that run 11s but blow their motor after about 6 months to a year.

if anything, we need to pay attention to what the guys on mr2oc.com are doing

gt_turbo
02-18-2005, 01:22 AM
cool findings conrad. keep us updated with the info

GT4SOM
02-18-2005, 02:53 AM
the other thing to remember is that dsm guys do dumb things all the time. i know guys that run 11s but blow their motor after about 6 months to a year.


That kinda reminds me of a boosted honda. Like Tom would say, " Its a rolling time bomb."

nuclearhappines
02-18-2005, 05:44 AM
DSM's have loggers, that is the huge advantage that they have over toyotas.

conrad, i'm with clay, notice the biggest difference between the ct-26 and the 14b seems to be the size of the turbine blade ...

also , are they made of the same materials ? i would weigh both to see how different it is... it may not be a huge difference but when you're looking for 100,000 rpms, a little bit of weight and a little bit of size difference may go a long way.

13G's are good for 250 hp, 14B's are probably good for close to 300 ...
the 13G is a TD04 though which makes it a quicker spooler (i guess that works bettwer with the longer gears of the auto) ... the 14b is a TD05 so it has a larger turbine housing

finally holding boost is not always the turbo, you have to think about this ...

if you have less cam/valve overlap ...
less exhaust duration
less valve float
and a more restrictive exhaust (or in some cases a more restrictive exhaust housing)

then you may be able to hold more boost ...this doesn't mean you can make more power... but the fact that a 14b can make, hold more boost than a ct-26 doesn't always mean that it will make more power... so comparing similar displacement engines is moot because the heads are different

-nuke

ChrisD
02-18-2005, 05:56 AM
You knwo what, Im with nuke. I think the 3SGTE people are just stuck on shit and afraid to try new shit out of the box. He has been talking to me about an AFM swap and nobody seems to want to investigate it. EVERYONE else out there can do it, supras, lexus, vettes, etc they all dick around with their AFM/injector combos with good results. Nobody seems to have to balls in the celica/mr2 world to do it. It just disgruntles me. Its like we have this kickass car and nobody knows how it really works, its like for all of our info we cant figure shit out..

sorry, disgruntled. My car doesnt work, fighting my fuckin battery light, just spent a bunch of money on it, etc. Im not feelin so hot about the whole thing right now.

Luni,

Thats very true. However, our community is FAAAAAR more willing to try new things than say...the MR2oc community. All they seem to be able to do (half the time) is recite out of the power primer and regurgitate info that only a select few "gurus" post. We have had some very cool conversations about what we can do around here, and things will get done...takes time, starts with one, then another, etc.

I have seen people do the famed supra-lexus AFM swap, and I've seen people pop engines by doing it too. In terms of AFM's, we are kind of hindered because ours read backwards from every other one on the market, save the rx7's.

That said, I am 100% going forward with the AFM to MAP conversion. I have sent out my supra TT injectors for cleaning, and ordered a wide band o2 sensor for tuning. I've got the SMT6 installed already. Right now I'm tending to a few other repairs while winter passes. So rest assured, I'll be doing the conversion very soon. :cool:

Chris

Conrad_Turbo
02-18-2005, 01:44 PM
I realize it comes to the VE of the engine along with the displacement that will affect the turbo...but the VE must be pretty drastic to have such a large difference in turbo design. I am not siding with one turbo or the other...it's just odd how the 3s community complains about the CT26, I want to find the flaws and make it into a potent turbo. I guess you could say I am doing the research that ATS has already done.

Nuke I have some scales at work...not super super accurate but enough to get a decent comparison between the two. I can post the results on Monday.

ChrisD
02-18-2005, 04:20 PM
And another comparison...the CT26 is a giant compared to the rx7's turbo!

Luni
02-18-2005, 04:41 PM
Chris Im going to work with Nuke on figuring out how to switch AFMs to a larger unit that will power some 550s correctly.

It has to be possible without a huge ass cost to us.

ChrisD
02-18-2005, 05:01 PM
As soon as I do my conversion I can probably be of some help for people interested in figuring out the conversion #'s too.

nuclearhappines
02-18-2005, 06:45 PM
conrad, you've taken your stock ECU out ? ... can you get us close up pics of the inside of a 3sgte ecu ?

just wondering... maybe there's some eeprom tuning we can do there

if i get another 5sfe celica i'd really like to crack the 5sfe ecu ... to be able to do some cool stuff without a piggy back ... (computer switchable nitrous systems, higher rev limiters, altered timing maps, altered fuel maps for larger injectors) ...

i know jet does it supposedly... i'm not trying to reinvent the wheel... i'm trying to gain full control over something i don't feel the toyota camp has control over

and if we figure it out ,we can remap a STOCK 3sge ECU for a map conversion, possibly unlock the supposed 18psi fuel maps ... you realise how cool that would be ?

-nuke

Luni
02-18-2005, 07:02 PM
Nuke, Id get a 3SGTE ECU and send it to you so you could rip it apart and see how it works if you thought it would help.

Conrad_Turbo
02-18-2005, 07:29 PM
Luni's post is an example of what makes me love this community...giving things to other members to benefit the group. :D

Nuke there are so many questions I have to all those myths out there...that I really want to start solving them and putting an end to old wives tales. I haven't taken my ecu out (as I daily drive my car) but reprogramming and such is well beyond my league. Haha.

What I would also like to figure out though is why the MR2's have higher fuel maps than the Celicas...ESPECIALLY since Chris found out that the AFM is 100% wide open at low boost levels. Also the fact that the ecu controls the air/fuel mixture by the afm reading, not the sensor that monitors boost. So I almost wonder if the MR2's have different AFM's and the ecu's to compensate for that? I really don't know.

This thread is totally off topic...but I think this is a good brainstorming thread to disucuss projects and things we plan on doing to get rid of these old myths with the 3sgte engine.

ChrisD
02-18-2005, 08:17 PM
Conrad,

What makes you say that mr2's have higher fuel maps?

Luni
02-18-2005, 08:44 PM
The mr2 uses the rpm signal and the afm signal to determine stuff I think.

Conrad_Turbo
02-18-2005, 09:29 PM
Conrad,

What makes you say that mr2's have higher fuel maps?

I vaguely remember hearing the mr2's having higher fuel maps than the Alltrac...I don't see how that is possible since they should have the same afm, ecu and whatnot. Maybe I'm just going crazy? :laugh: FYI I've had no sleep the last few weeks, even less than usual!

nuclearhappines
02-18-2005, 10:02 PM
robert i appreciate it but i want to start with a few N/A ecu's (5sfe, 3sge, 4age) possibly and see how they do it ... mostly looking for timing maps ...

if i can figure out timing then that opens up room for N/A , Boost and N2O tuned stock ECU's ... like i can give you an ecu with an advance to say 3000 and a retard from 3500 up

so you can have better throttle responce and N/A power at lower rpms ...and you can be boost friendly up top ...

that's something we don't have access to yet and it would make a world of a difference imho if people knew how to do this and we went from there to doing things like putting down 'base maps' for say 3sgte with a map sensor on 660 cc injectors

if we can do that with a rom program (costs us nothing really) then you can just go out and bolt on your td06-20G and it would be roughly tuned for it...with the right fueling , with no side effects of timing like it would with a piggy back ... because we'd have independant control

sorry for the OT
but it's an early 90's OBD-1 ECU ... it should have an eeprom and it should be straight forward figuring it out

-nuke

nuclearhappines
02-18-2005, 10:06 PM
see when you have this kind of access, and you know that your AFM is a 5-0 and most are a 0-5

well i can go into the chip and just swap the entire table and reburn it ... so that the first column represents 5 volts instead of the last column and presto you can now use an opposite voltage snesor ...

it just REALLY opens things up.

Conrad IIRC the G-Force upgrade to the mr2 ecu unlocks fuel maps up to 18psi , changes redline and possibly retunes a bit.

I know CS edition and GRP A ecu's also have similar extended fuel maps ...

Trance4c
02-18-2005, 11:52 PM
Ok.. I have a lot to post.. but first..

Nuke - I have my old 5S-FE ECU, its all yours.. just let me know where you want it shipped.

Conrad_Turbo
02-19-2005, 01:11 AM
see when you have this kind of access, and you know that your AFM is a 5-0 and most are a 0-5

well i can go into the chip and just swap the entire table and reburn it ... so that the first column represents 5 volts instead of the last column and presto you can now use an opposite voltage snesor ...

it just REALLY opens things up.

Conrad IIRC the G-Force upgrade to the mr2 ecu unlocks fuel maps up to 18psi , changes redline and possibly retunes a bit.

I know CS edition and GRP A ecu's also have similar extended fuel maps ...

Nuke you're the electrical guru here, I am sure you can pull it off! There is so much unknown to this engine/ecu that it's pretty pathetic since it's a 15 year old car...not even including the 165's! Jeez.

I think if we all work at projects to tear apart Toyota's designs and that will allow us the flexibility to do what we want with our cars. There is a lot of talent here...not a bunch of guys that sit on their hands or people that go to jeggggs to buy intakes for their cars, but truely people who have the technical background to design and build new components. People like that is what gives this board the name and rep it deserves. :D

I don't have the internet at home yet...but I will be doing more looking into the CT26 this weekend. I will also be rebuilding a Supra CT26 on Saturday, so I can compare the two when I have them both in my shop.

Lagos
02-19-2005, 04:42 AM
http://gtfour.supras.org.nz/mapsensor.htm

some good info on the map sensors voltages. should help with the afm conversion project.

galcrazi
02-19-2005, 02:00 PM
ok.. dont know if this is common knowledge or not but I'll share since it was brought up. I apologize if im straying off topic:

Rom board can be switched out with a blank one that has been programed. This is how SARD does our ecu's. Problem is... a blank board is around $300-400 (from what u understand plz correct if im wrong). Some ppl have ripped the SARD program and placed it on these blank boards. Iv'e been told the the software needed to crack the hex code on our current boards is upwards of $8000. Sorry for going off topic, but this info was given to me by a shop tech who is VERY familiar with tuning and building 2nd and 3rd gen 3s mr2's.

Snafu
02-20-2005, 06:13 AM
Well, shit, why can't we use the same ROM boards that the honda guys use for Uberdate/TurboEdit? Is it that much different? If you can do that, then it's all just software and chip burners.

nuclearhappines
02-20-2005, 07:47 AM
OT: clay is sending me his old 5sfe ecu... i might also pick up a 3sge ecu as i see those on ebay for 10 bux ...

let's see what i can find... if it looks promising i may actually put a good amount of money into this (but no where near 8000) ... let's just see what i find.

As stated before, we can always rip off the GForce, XS, and Jet chip tunes... but i'd rather figure out how the thing works to finally get cheap , fully customizable, independant fuel and timing control ...

then i can make my own 5sfe nitrous , turbo , big turbo maps...and the same for the 3sgte

like if i could unlock the higher psi maps (that supposedly already exist on the 3sgte ecu) and i could pull say 0.25-0.5 degree per psi for those 12-18psi we could see alot more 3sgte's running 18psi daily setups on 93 octane (with the use of a 2.5 or 3 map sensor) ... i think something like that would be huge

I think the afm to map or afm to hotwire conversion would be huge too
I'd like to figure out rev limits and possible two step interface too
Altering the TVIS engagement point would be nice , i think stock TVIS is too late for modded cars.
I'd also like to figure out how the ECU runs it's closed loop corrections.... and possibly modify it to accept a newer somewhat wide band o2 sensor (like the one on all honda ULEV vehicles) essencially turning a 5sfe/3sgte into an ULEV ...
Maybe extend that to modifying the ECU to run closed loop even at WOT now that it has a WBO2 on it ?
Fixing the 2200-2500 lean spot in modded 5sfe's
Leaning out the 5sfe/3sgte top end
Coming up with high rpm timing advance for the 5sfe to combat the torque drop off (i'm probably going to base the advance numbers on how the 2 bar setup advances timing on a stock ECU, because we know that is a safe amount of advance)
larger injectors for all motors (5sfe on 440s and 550s, 3sgte on supra injectors and whatever is the next up convenient size 620s?)

in the end i want a product that you can customize off my website

engine: 5sfe.3sge.3sgte.4age.7afe.4afe ...etc
setup: turbo.nitrous.n/a
rev limit: stock , other
injectors: stock, other
afm: stock, other << we'd have to pick some afm or map to kind of standardize this ...something with good flow characteristics, something that can say read up to 400hp
special requests : (this part would be really easy if you had a dyno showing where you had rich/lean spots in your factory tune... we can just go from there and adjust the IDC to fix them which will give you a better baseline, if not a perfect tune) ...


again sorry for the OT. ... but that's just some of the stuff i was thinking about htis morning

Conrad_Turbo
02-21-2005, 02:05 PM
Good info guys! Keep it going! I typed up this last night (don’t have time to write up long posts at work) about the CT26 and how I compared them.

Over the weekend I have had plenty of time to research and do my own analysis on the CT26 turbo (dual and single entry). This has all to do with the comparison of compressor/turbine wheels and their effects.

#1. CT26 exhaust side is restrictive.

I don’t think that this is true when comparing the turbine since it uses the EXACT same turbine blade as on the 3.0L 7M-GTE Supra. So the wheel is definitely not the problem in this case, it must rely with the housing if this is true. The exducer and inducer diameter are the same for both the dual and single entry CT26, the blade pitch and curvature are the same as well.

Why do people upgrade the trim on the compressor side…especially if the exhaust side is supposedly so restrictive? If anything using a larger trim compressor side would yield the same hp results, simply because if you are trying to stuff more air in…in the meantime the exhaust still won’t let it out. What’s the point of working the compressor side so hard? Again, I think there is a lot of misinformation about the exhaust side being the limitation to the CT26.

Comparisons

Now for the comparison of the CT26 (dual and single entry) to various Mitsubishi and other turbos, see the following excel file I created.

http://img.photobucket.com/albums/v622/mixman1982/TurboWheelSizeComparison.jpg

I calculated the trim of both the Supra and dual entry CT26…they are quite different on the compressor side (as we all have known for years). The thing I found interesting is that you can use the dual entry housing, center section and just install a single entry compressor along with the front housing…tada you’ve got a 50 trim compressor with a dual entry exhaust housing for next to nothing. Something interesting I found. :D

Now comparing my results, I created a ratio for the compressor and turbine, they both compare the inducer/exducer diameter (compressor) and exducer/inducer diameter for the turbine. Now creating an overall ratio allows me to compare the ratio of the trim (which is derived from the ratio) of the compressor to the turbine. Notice how low the dual entry CT26 is to the rest of the turbos on the list. Now that just strictly compares ratios, now for the % Ratio, that is compared by the inducer of the compressor divided by the exducer of the turbine (basically comparing the physical size between the two in a % format). Now you can see that the dual entry CT26 is disproportioned as compared to the rest…considering the average of that list is 0.974 and it reads 0.796.

So looking at all of this makes me realize that the reason why the CT26 runs out of steam after 15psi isn’t because it is so restrictive in the exhaust…it’s because the turbine has to spin so horribly fast to get anymore air into the intake tract. The higher speed it spins the efficiency drops (especially when going over 100,000rpms), so that’s why we are getting super heated intake air. I don’t see how exhaust backpressure can equate to putting out super heated intake air after 15psi…only if it was an internet myth…

I don’t keep tabs on what things people are doing out there, but have swapping Supra compressor wheels and housings onto dual entry CT26’s been happening? That’s what I plan on doing with the turbo I have in the shop right now. You get a better % ratio (even though it’s still under the average) and still retain the dual entry exhaust side.

Have I bored you guys enough yet?

DrPaine
02-21-2005, 04:06 PM
Actually Conrad, Im following along very closely!! :bigthumbu

mikeswickednick
02-21-2005, 04:13 PM
the reason i think that people in our comunity are less agressive with our cars is b.c of the price of things... a mr2 is costing sooooo much now-a-days hell im still paying off my turbo

ChrisD
02-21-2005, 05:40 PM
Conrad thats some AWESOME info! Keep it coming! This is totally the kind of stuff that should make it into the web based sections of the site that I'm working on.

nuclearhappines
02-21-2005, 05:58 PM
conrad

1- You're great : )
2- Your info is great

A few things:

yes the supra CT_26 has been done... i think it's on alltrac.net's info page... i preached it for a while and clayton and keyroo both gave it a try with good results...

after going to the DSM/3000GT community and coming back... the CT-26 is HUGE it's just not used right

Conrad, can you do a few things for me, in your spare time : )...

1- what do you think the optimum intake side would be to reach an average ratio ?
2- Internet here say says that a 54 trim with a 10-12* clip is the best intake wheel on a ct-26 ... can we somehow insert that in your chart ?
3- I can't but help think about how much larger all the ct-26 internals seem compared to the 14b... can you maybe take a look at their bearings and see if you think the ct-26 lubrication seems adequate for such a hefty sized turbo, at least in comparison to the 14b?

thanks

-nuke

Trance4c
02-21-2005, 06:04 PM
Conrad - My 60-1 compressor CT26 was originally a Supra single entry. so yes.. there are people out there with these swap turbos running them like myself. I just did the twin entry exhaust housing swap and reclocked it back to the stock angles so the compressor housings outlet was pointed back towards the intake.

I have finally put 4000 miles on this engine and disabled TVIS last night. Fucker pulls CRAZY!

As far as the exhaust turbine being our limit.. I think this is why so many people going with a clipping. They try to flow more air over the turbine blades so that they can hold higher psi without super heating the air. The question i have is that what exactly about the exhaust turbine is so restrictive? In comparison, the stock turbo is VERY large as you have stated, so how can it be so restrictive when compared to the Mitsu little pee shooter turbo?

nuclearhappines
02-21-2005, 07:47 PM
clay

what he's saying is that it is not restrictive at all ... it's the intake side that is restrictive... basically what htis says is that the ct-26 has a huge exhaust side (big lag) and a tiny intake side (bad flow) ...

and the tiny intake side masks up the fact that the exhaust side is lagger ...and makes the intake side responsible for the ct-26 quick spool (rather than most manufactures that set their spool times with a restrictive exhaust side)...

and as people upgrade their intake side they seem to be upset that they are losing spool time and lots of it... and by limiting themselves to 15psi only picking up a little bit of psi/hp in the higher rpms ... so they have a narrower powerband


the problem with the ct-26 exhaust side and the rest of the turbo in general... is probably its heft rather than its balance... again you want to spin this thing between 60,000 and 100,000 rpms... which is probably why the ct-20b (although being a smaller turbo and probably even more inadequate in it's in/ex ratio) is so popular

is the ct-20b ceramic on both sides ? if so then a ct20 ex side + a ct-26 supra side might be the best ct-26 turbo out there

EDIT:
http://gtfour.supras.org.nz/3sgte%20table.htm

-nuke

Conrad_Turbo
02-21-2005, 08:01 PM
so how can it be so restrictive when compared to the Mitsu little pee shooter turbo?

I don't think the exhaust side is the restriction at all...I think the limitation is the intake side. If you upgraded your compressor and left your exhaust side you should have the same problem flowing X amount of air, now you have a larger turbine that will flow more air...doesn't make sense. Especially since you are getting more power.

Clay I gotcha, you swap the exhaust housing, while I was thinking the other way around (swap the compressor and the compressor housing from the Supra). The center section doesn't really make a difference anyways (since they are internally the same).

I know hundreds have clipped the exhaust turbines...but personally from what I have seen myself I think this is a case where someone follow someone else and so on and on...now it seems common to clip the exhaust to get more top end power. Who's to say that the original person didn't know what he/she was doing?

Nuke in answers to your questions:

1- that's the thing...I don't know. I just wanted to compare our turbo to others...and see if I could find a pattern or weird glitch. But you can see there is a weird glitch and it's the just due to the imbalance of the compressor to the exhaust...showing that the compressor is too small, not the turbine. I guess to determine an an ideal average ratio you'd need to see compressor maps of all the different turbos...but they'd need to have similar A/R to be relevant. There are so many variables to play with...but we've gotta start somewhere and not to become overwhelmed with all the other unknowns.
2- here is a 54 trim compressor on a dual entry CT26...clipping of the turbo wouldn't affect the ratio at all...so with this spreadsheet we have to assume these are all unclipped turbos.

http://img.photobucket.com/albums/v622/mixman1982/TurboWheelSizeComparison2.jpg

3- if anything I'd be worried about the CT20B for lubrication since the turbine shaft is smaller in diameter. I can compare the 14b to the ct26 bearing sizes and quality of lubrication (bearing area), but other than that there isn't much more I can do.

All in all I'm just trying to get a fair comparison between our CT26 and any other turbo...but it's tough to do! Haha.

Trance4c
02-21-2005, 09:06 PM
Alright.. guess I read it wrong.

As for clipping.. I went without a clipping on my exhaust side. Why, because it seems that those that have clipping or more clipping on the MR2 dyno registry lost torque. I couldn't understand why you would clip the turbine and lose torque would be a good thing. So thats why I didn't do it.

Conrad_Turbo
02-21-2005, 09:50 PM
On the ATS upgrade...is it proven that they do some machine work to the exhaust side casting? Or is this just more internet hearsay, does ATS upgrade the compressor side on their CT27 turbo? I have a feeling everyone has been looking in the wrong direction and ATS went the opposite way and is making money off of it. Just a suspicion, I like thinking outside of the box. :D

As for the clipping, that will improve the VE at the top end but hurt the VE in the lower end. Another thing to consider is blade design, maybe due to the blade design that is why the CT26 is so large in size? I really don't know...but I'd like to find out.