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which turbo is best


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Confusion.

:confused: I am confused(as always:cheesy: )
So, I went to the garrett website and read through the three "lectures" they have there(very interesting stuff, check it out)Anyways, I was thinking about far-far optimistic/dream future of 750hp at the crank and calculating what trubo I would need. The results were surprising. Using 13 as A/F, brake specific fuel consuption as .55 and 750hp as the target hp I got 89.375 as the needed airflow. From the numbers, that is very conservative.
FOr the boost, for 750 crank hp, 2.3L 8000rpm engine, I got absolute pressure as 65.3psia, which would at the sea level equal to 50.6 psi of turbo pressure. Using 4psi as a loss of pressure from turbo to the cylinders and using 1psi as pressure lost from the atmosphere to the turbo, the pressure ratio is 5.06 for this set up.
Now, if you go here: http://www.maptun.com/cars.php?id=30 you will see that this gentleman claims 600hp. If we account for conservative 15% drivetrain loss, it would end up as about 700hp which is near the target hp calculated above. Now, he claims all of this with GT40 turbo. If you look at the compressor map for GT40, there is NO WAY it can accomodate the pressure ratio and the airflow for this hp (http://www.turbobygarrett.com/turbobygarrett/catelog/Turbochargers/GT40/GT4088_703457_2.htm)
Now, what the trick here? I do believe that this guy has the hp, but the numbers just don't stack up...
It looks like there is no turbo for this application at all. GT45 looks like it is dead on for the airflow, but it doesn't supply nearly enough boost(http://www.turbobygarrett.com/turbobygarrett/catelog/Turbochargers/GT45/GT4508R.htm)
Monster like GT55 supplies enough pressure ratio, but at much higher airflow. At airflow around 90 which we need it still cannot supply enough boost, therefore this turbo will have TONS of lag and will make MUCH more power then 750hp...(http://www.turbobygarrett.com/turbobygarrett/catelog/Turbochargers/GT55/GT5533_769112_1.html)

So, what do you guys make of it?

Klim
 

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mulik51 said:
:confused: I am confused(as always:cheesy: )
So, I went to the garrett website and read through the three "lectures" they have there(very interesting stuff, check it out)Anyways, I was thinking about far-far optimistic/dream future of 750hp at the crank and calculating what trubo I would need. The results were surprising. Using 13 as A/F, brake specific fuel consuption as .55 and 750hp as the target hp I got 89.375 as the needed airflow. From the numbers, that is very conservative.
FOr the boost, for 750 crank hp, 2.3L 8000rpm engine, I got absolute pressure as 65.3psia, which would at the sea level equal to 50.6 psi of turbo pressure. Using 4psi as a loss of pressure from turbo to the cylinders and using 1psi as pressure lost from the atmosphere to the turbo, the pressure ratio is 5.06 for this set up.
Now, if you go here: http://www.maptun.com/cars.php?id=30 you will see that this gentleman claims 600hp. If we account for conservative 15% drivetrain loss, it would end up as about 700hp which is near the target hp calculated above. Now, he claims all of this with GT40 turbo. If you look at the compressor map for GT40, there is NO WAY it can accomodate the pressure ratio and the airflow for this hp (http://www.turbobygarrett.com/turbobygarrett/catelog/Turbochargers/GT40/GT4088_703457_2.htm)
Now, what the trick here? I do believe that this guy has the hp, but the numbers just don't stack up...
It looks like there is no turbo for this application at all. GT45 looks like it is dead on for the airflow, but it doesn't supply nearly enough boost(http://www.turbobygarrett.com/turbobygarrett/catelog/Turbochargers/GT45/GT4508R.htm)
Monster like GT55 supplies enough pressure ratio, but at much higher airflow. At airflow around 90 which we need it still cannot supply enough boost, therefore this turbo will have TONS of lag and will make MUCH more power then 750hp...(http://www.turbobygarrett.com/turbobygarrett/catelog/Turbochargers/GT55/GT5533_769112_1.html)

So, what do you guys make of it?

Klim
yes, making 750hp from a 2.3 is possible. so is 2800hp. but driveability at these levels is not very good.
 

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I am not saying it is impossible. If you strap on T72 then you will get all the hp you want. I am just saying that for T40 750hp on our engines are WAY of the flow maps. So, theoretically it should behave like T25 does right now for my car, loose hp towards high rpm, because 270hp is WAY of the map for the T25 too.

More on topic, can you get different A/R turbine housings for T25?

Because I certainly don't have enough money to get a different turbo, but housing shouldn't be that expensive. So, theoretically, if I were to get a bigger A/R turbine housing, I should get a bit more lag, but more top end hp, exactly what I am lossing now...

Klim
 

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Are we talking just a straight forward TD04?

Just a question, are we talking of just the diffrent type that are being used on the vehicles at present.

One must remember that yes, to say 'I run a TD04/T3/T25/TE05 on my car' but there are different TD04 turbo's out there with different specs.

If we are just generalizing - Fine.

If not - Lets clarify.

ie - My mate runs a TD04h15t on his Uno Turbo, with some magnificent results, which he swopped his TD04h13g with.

Just a thought.....use it, don't use it......
 

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A lot of us run TD04,s with modified compressors i.e. T18 or T19 or graft on a compressor from a garrett GT28 etc..
end result is a td04 good for an easy 350 crank hp 400 ft/lbs and - done right with very little negative low rpm lag
so yes - not all things are equal if you just say "Td04 or T25 etc..
 

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Is the T3 the same as a T3/T04b? I've had one of them sat upstairs for about 6 years now and was going to fit it to my Aero but went for the GT28RS instead. I cant find hardly any info on the turbo or what its capable of? Its a toss up between fitting either this or a GT3071Rwg next??? I'm aiming for 420-430 bhp next:cheesy:
 

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I love my T3. Recently smoked an 89 camaro z28 with a supercharger and 4" sidepipes that was "tuned", he was about .25 mile behind me at 120 mph :) waiting on a little money and going to upgrade to T3/T4 with .57 trim, 3" intake piping and turbo back exhaust
 

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A lot of us run TD04,s with modified compressors i.e. T18 or T19 or graft on a compressor from a garrett GT28 etc..
end result is a td04 good for an easy 350 crank hp 400 ft/lbs and - done right with very little negative low rpm lag
so yes - not all things are equal if you just say "Td04 or T25 etc..
Do you have any more info or a link to more info? This sounda like it might be a winner for my 9K!

Thanks!
Alex
 

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TE 05/Supra hybrid

Does anyone have any info or experience with the Supra compressor mod to a TE 05 as described in post #45 in this thread?

Which Supra turbo is the donor and what is the performance outcome/profile?

Thanks!
 

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This is an older thread, but it has a lot of valuable information, so I thought my questions would fit in here very well.

I am building a hot rod. Powerplant is a B234 2.3L motor from a 1995 9000. T5 5-speed transmission. And I have tall rear tires because this is a traditional style hot rod I am trying to build.

I read through this whole thread, and I have been digging through the Saab Central forums for a while. I don't know if I have definitive answers to these questions, so any real input and suggestions would be awesome.

When answering these questions, keep these factors in mind: I want a little more HP than stock. maybe 240-250 HP and Torque. And since I have tall tires, I think torque might be more important. And I have the engine and ECU, but I do not have any of the turbo parts, exhaust manifold, boost controller, or any of that. So turbo suggestions do not have to bolt to the stock motor. I will be making the manifold.

1. Which turbo should I go with? And I am not too familiar with turbos, so the more details you can give me, the better. Hell, even drop a link to one I can buy.

2. Since I am not familiar with turbos, and I don't have the complete stock engine, what would you suggest for boost control, wastegate,blowoff valve, and any other turbo accessories I might need.

Many thanks.
 
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