I spent 3 hours yesterday doing the formulas so i could trying to see if the T61 turbo with a .70 trim i have is able to be ran on my ka24de. From what the map says.. I would have to run 7psi of boost to even be in the opertaing Efficiency.. If i run anything higher than for the first 1000, 2000, rpm I am out side of the surge limit... then for 3000, 4000, 5000, 6000, 7000 rpm range I am in the turbos about 55%, 60%, 65%, 70%, and 75% efficiency range? I did all these formulas useing 150Deg temp 7psi of boost and a 147.43 CID because the engine will be .20 over bore.
My question is after ploting the points on the map of the compressor houseing how do i fully understand all this data... I know if im out side of the surge area and if im in side the turbos efficiency... but what does that mean in terms of spool up... ? Because doing the same formulas useing 20psi boost then the turbo is in the surge limit till about 5000rpm then from 5 to 7 its in about 60% efficiency... Is it ok if the turbo is set up that way or should I not run a T61 with a .70 trim ?
I know running out side the surge limit can hurt the turbo ? so thats what im affraid of most... So i thought i can run a dual stage boost controller so bellow 4000rpm it runs 7psi than above 4000 it will run 20psi
Thanks for any help
Ka-T, Turbo Mapping formulas and questions about Efficiency
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C-Kwik
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Re: Ka-T, Turbo Mapping formulas and questions about Efficiency (uvamosk)
A T-61 is on the big side for a KA. From my calculations, you'll never take full advantage of the peak efficiency as you won't even get past the center of it by redline. If you use this turbo, a rather large turbine will be needed. While it would seem to me you'ld have a bigger cusion than other large frame turbos from surge, it's still a concern if you sized the turbine to boost too early. But if you received a standard T-61(not to custom specs), then it will probably already have a well matched turbine for the compressor. But on a KA, it will have a high boost threshold. It would likely work, but it won't be the best match. I'd only run it on a KA if I had a KA that could handle 8000 RPM. And I'd probably not bother if I am running less than 8-9 psi.
Thanks for the replies and the help...
Ok here we go
I have a ka24de with wiseco pistons bored .20 over at 9:1Crower rods3angle valve job1mm over sided SS valvesSS valve springsTitanum RetainersPorted head
The turbo Says on it Type T3, then Part NO. Super T70
im going to have a JWT ecu with 50lbs injecters and z32 maf with a Walbro Fuel pump feeding it all. and a Safc2 To tune it all out nice and smooth.
Here is the link to the turbo... from ebay that is the same thing.. http://cgi.ebay.com/ebaymotors...ZWDVW
The reason im running this turbo is because I got the turbo, 38mm Waste gate, Cast iron manifold with center placed waste gate, BOV and boost controller all for 700$ with every gasket and part i need to hook it up... Everythings still in its boxes never opened I just want to try and find out what boost i can run on this turbo with my engine build thats why I was trying to run these maps and see what i could find out.. I dont want to over boost or underboost the engine.. My goal is 400WHP and 430 to 450Whp with Nitrous Direct port
Thanks
Ok here we go
I have a ka24de with wiseco pistons bored .20 over at 9:1Crower rods3angle valve job1mm over sided SS valvesSS valve springsTitanum RetainersPorted head
The turbo Says on it Type T3, then Part NO. Super T70
im going to have a JWT ecu with 50lbs injecters and z32 maf with a Walbro Fuel pump feeding it all. and a Safc2 To tune it all out nice and smooth.
Here is the link to the turbo... from ebay that is the same thing.. http://cgi.ebay.com/ebaymotors...ZWDVW
The reason im running this turbo is because I got the turbo, 38mm Waste gate, Cast iron manifold with center placed waste gate, BOV and boost controller all for 700$ with every gasket and part i need to hook it up... Everythings still in its boxes never opened I just want to try and find out what boost i can run on this turbo with my engine build thats why I was trying to run these maps and see what i could find out.. I dont want to over boost or underboost the engine.. My goal is 400WHP and 430 to 450Whp with Nitrous Direct port
Thanks
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C-Kwik
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- Joined: Thu Aug 01, 2002 9:28 pm
- Car: 2013 Chevy Volt, 1991 Honda CRX DX
Looking at the link, I'm a bit concerned. without knowing anything about the turbo actually posted there, is it actually a Garrett Turbo? It only says it is similar to the T-61. If the compressor design is not the same, then the compressor mapping will be different. It's a bit hard to tell, but from the photos, it doesn't look like a T4 turbine. It could be the angle of the photo though.
However, if the compressor is a T-61, then for your goals, it can probably work fine. Cost-Benefit is always something to consider, but do not expect it to have a low boost threshold. Ifthe turbine is or is similar to a T4 turbine, then I'd expect it will have some decent overall efficiency towards redline at the power level you want. For the cost, it's not bad considering your goals. Not my first choice in turbos(if it's a T-61), but it should do the job.
However, if the compressor is a T-61, then for your goals, it can probably work fine. Cost-Benefit is always something to consider, but do not expect it to have a low boost threshold. Ifthe turbine is or is similar to a T4 turbine, then I'd expect it will have some decent overall efficiency towards redline at the power level you want. For the cost, it's not bad considering your goals. Not my first choice in turbos(if it's a T-61), but it should do the job.
Thank you so much for helping me out... Here this is a better picture of it http://cgi.ebay.com/ebaymotors...wItemThat looks exactly the same as what i got but I dont know what the A/r is and the trim But i belive that its the same as the one on that ebay link...
If you can let me know anything from that please
If you can let me know anything from that please
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C-Kwik
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If that is the turbo you have, then it has a T3 turbine. Might be dangerous to use. A larger trim T3 with a large A/R 'might' be okay. I'd be concerned about it spooling to early and the airflow being in the surge area.
However, looking at it even closer, I'm not sure about the size of the compressor. It states the compressor to have a 60.5mm trim. I would assume it's referring to the major diameter, in which case, it would size close to a T3(though I could not imagine a T3 supporting 650 HP asa it claims). If that diameter was the minor, then maybe it could be a T-61, but then they list a 64.5mm trim for the turbine. I do not know of any T3's with an exducer diameter that large. If it is indeed that large though, you might be okay as far as surge is concerned. But I would expect it to spool like a T4 turbine. And to add on to this, the T3 doesn't have a .84 A/R listed in my turbonetics catalog. However, there are plenty of T4 in the .84 A/R variety. I did just notice a Euro spec T4 housing listed there. The angle of the photo makes it difficult to tell, buut the shape of the flange looks rather T3ish. Maybe it is actually a T4 turbine.
What may be helpful here is to know the actual major and minor diameters of the compressor and turbine wheels.
However, looking at it even closer, I'm not sure about the size of the compressor. It states the compressor to have a 60.5mm trim. I would assume it's referring to the major diameter, in which case, it would size close to a T3(though I could not imagine a T3 supporting 650 HP asa it claims). If that diameter was the minor, then maybe it could be a T-61, but then they list a 64.5mm trim for the turbine. I do not know of any T3's with an exducer diameter that large. If it is indeed that large though, you might be okay as far as surge is concerned. But I would expect it to spool like a T4 turbine. And to add on to this, the T3 doesn't have a .84 A/R listed in my turbonetics catalog. However, there are plenty of T4 in the .84 A/R variety. I did just notice a Euro spec T4 housing listed there. The angle of the photo makes it difficult to tell, buut the shape of the flange looks rather T3ish. Maybe it is actually a T4 turbine.
What may be helpful here is to know the actual major and minor diameters of the compressor and turbine wheels.
Ok im going to try and email the ebay member that lists these and try to get some specs see what i can come up with they say it compaies to the T61 map for comparison so im guess you might be right about it being close to a T61... other than that I dont really know.. It came in a Ka24de Turbo kit...
Thanks
Thanks
Re: (C-Kwik)
http://cgi.ebay.com/new-big-T7...wItem
That links shows exactly what I have all the specs and everything... all the way down to the name plate on the comp housing... If you could tell me anything please ... about that... It says he was running on a Celica which is a 2.0l and was making boost at 3800rpm... !!
So i dont know what to go by..
Thanks
That links shows exactly what I have all the specs and everything... all the way down to the name plate on the comp housing... If you could tell me anything please ... about that... It says he was running on a Celica which is a 2.0l and was making boost at 3800rpm... !!
So i dont know what to go by..
Thanks