Garret Turbos
#2
Hi Slow...
Here's the issue we have with Garret turbos over VTG's. To be perfectly and brutally honest, there are several fundamental changes that have to be made to the foundation of the 997 Turbo in order to use Garret turbos.
For one, in order to run a Garret turbo, you have to allow the ECU to completely relinquish it's control over boost. Boost has to be controlled by an external controller, something like a GReddy profec, etc. When you do that, the boost is controlled 100% by the profec, without any input from the ECU about knock, ignition, lambda, etc. Essentially, you have to back-date the technology in the car, something that goes against our principles. We prefer to advance the existing technology rather then abandon it.
Secondly, we assume you have to allow vacuum to control the turbo wastegates with different wastegate spring rates. Another thing we just don't know how to do safely without ECU control. Our GIAC datalogger monitors 600% more parameters of the ECU then a Durametric, none of which help us understand how to safely control boost.
Third...you have to make permanent and irreversible modifications to the car...cutting oil lines, etc. (see pic below). Again, can it be done, yes. Can it be reversed....for a lot of money, yes.
And finally...the main reason we stick to VTG turbos is performance. Sure, Garret turbos seems to boast higher HP output...but not much of an increase in TQ over VTG's. So real world performance just doesn't seem to show enough of an advantage to make it worthwhile. We're able to product 700 lb/ft of TQ as low as 4000 rpm's and maintain it past 7000 rpm with our 68mm VTG's. That's an incredibly broad range of power!!
Other tuners have successfully been able to run Garret turbos obviously. Hopefully one of them can chime in with some more technical information about how exactly this type of setup works.
Here's the issue we have with Garret turbos over VTG's. To be perfectly and brutally honest, there are several fundamental changes that have to be made to the foundation of the 997 Turbo in order to use Garret turbos.
For one, in order to run a Garret turbo, you have to allow the ECU to completely relinquish it's control over boost. Boost has to be controlled by an external controller, something like a GReddy profec, etc. When you do that, the boost is controlled 100% by the profec, without any input from the ECU about knock, ignition, lambda, etc. Essentially, you have to back-date the technology in the car, something that goes against our principles. We prefer to advance the existing technology rather then abandon it.
Secondly, we assume you have to allow vacuum to control the turbo wastegates with different wastegate spring rates. Another thing we just don't know how to do safely without ECU control. Our GIAC datalogger monitors 600% more parameters of the ECU then a Durametric, none of which help us understand how to safely control boost.
Third...you have to make permanent and irreversible modifications to the car...cutting oil lines, etc. (see pic below). Again, can it be done, yes. Can it be reversed....for a lot of money, yes.
And finally...the main reason we stick to VTG turbos is performance. Sure, Garret turbos seems to boast higher HP output...but not much of an increase in TQ over VTG's. So real world performance just doesn't seem to show enough of an advantage to make it worthwhile. We're able to product 700 lb/ft of TQ as low as 4000 rpm's and maintain it past 7000 rpm with our 68mm VTG's. That's an incredibly broad range of power!!
Other tuners have successfully been able to run Garret turbos obviously. Hopefully one of them can chime in with some more technical information about how exactly this type of setup works.
Last edited by Tom@Champion; 07-28-2011 at 07:31 PM.
#3
lol, Slow are you thinking the car won't be fast enough before you even have it???
Rumour has it that vtgs are very sensitive to egts. Lots of rumours abound about everything turbo related so I'll patiently wait for the proof of the pudding. mmmmm...pudding.
Rumour has it that vtgs are very sensitive to egts. Lots of rumours abound about everything turbo related so I'll patiently wait for the proof of the pudding. mmmmm...pudding.
#4
If you install Alpha turbos, you don't have to mod your oil/cooling lines...
Hi Slow...
Here's the issue we have with Garret turbos over VTG's. To be perfectly and brutally honest, there are several fundamental changes that have to be made to the foundation of the 997 Turbo in order to use Garret turbos.
For one, in order to run a Garret turbo, you have to allow the ECU to completely relinquish it's control over boost. Boost has to be controlled by an external controller, something like a GReddy profec, etc. When you do that, the boost is controlled 100% by the profec, without any input from the ECU about knock, ignition, lambda, etc. Essentially, you have to back-date the technology in the car, something that goes against our principles. We prefer to advance the existing technology rather then abandon it.
Secondly, we assume you have to allow vacuum to control the turbo wastegates with different wastegate spring rates. Another thing we just don't know how to do safely without ECU control. Our GIAC datalogger monitors 600% more parameters of the ECU then a Durametric, none of which help us understand how to safely control boost.
Third...you have to make permanent and irreversible modifications to the car...cutting oil lines, etc. (see pic below). Again, can it be done, yes. Can it be reversed....for a lot of money, yes.
And finally...the main reason we stick to VTG turbos is performance. Sure, Garret turbos seems to boast higher HP output...but not much of an increase in TQ over VTG's. So real world performance just doesn't seem to show enough of an advantage to make it worthwhile. We're able to product 700 lb/ft of TQ as low as 4000 rpm's and maintain it past 7000 rpm with our 68mm VTG's. That's an incredibly broad range of power!!
Other tuners have successfully been able to run Garret turbos obviously. Hopefully one of them can chime in with some more technical information about how exactly this type of setup works.
Here's the issue we have with Garret turbos over VTG's. To be perfectly and brutally honest, there are several fundamental changes that have to be made to the foundation of the 997 Turbo in order to use Garret turbos.
For one, in order to run a Garret turbo, you have to allow the ECU to completely relinquish it's control over boost. Boost has to be controlled by an external controller, something like a GReddy profec, etc. When you do that, the boost is controlled 100% by the profec, without any input from the ECU about knock, ignition, lambda, etc. Essentially, you have to back-date the technology in the car, something that goes against our principles. We prefer to advance the existing technology rather then abandon it.
Secondly, we assume you have to allow vacuum to control the turbo wastegates with different wastegate spring rates. Another thing we just don't know how to do safely without ECU control. Our GIAC datalogger monitors 600% more parameters of the ECU then a Durametric, none of which help us understand how to safely control boost.
Third...you have to make permanent and irreversible modifications to the car...cutting oil lines, etc. (see pic below). Again, can it be done, yes. Can it be reversed....for a lot of money, yes.
And finally...the main reason we stick to VTG turbos is performance. Sure, Garret turbos seems to boast higher HP output...but not much of an increase in TQ over VTG's. So real world performance just doesn't seem to show enough of an advantage to make it worthwhile. We're able to product 700 lb/ft of TQ as low as 4000 rpm's and maintain it past 7000 rpm with our 68mm VTG's. That's an incredibly broad range of power!!
Other tuners have successfully been able to run Garret turbos obviously. Hopefully one of them can chime in with some more technical information about how exactly this type of setup works.
#5
I have no desire to change things...............Porsche chose the design for good reason surely. ****! You never can go fast enough.
Last edited by Slow911TT68Tip; 07-29-2011 at 05:42 AM.
#7
did not know that. but you still need ebc though.
Trending Topics
#8
Hi Slow...
Here's the issue we have with Garret turbos over VTG's. To be perfectly and brutally honest, there are several fundamental changes that have to be made to the foundation of the 997 Turbo in order to use Garret turbos.
For one, in order to run a Garret turbo, you have to allow the ECU to completely relinquish it's control over boost. Boost has to be controlled by an external controller, something like a GReddy profec, etc. When you do that, the boost is controlled 100% by the profec, without any input from the ECU about knock, ignition, lambda, etc. Essentially, you have to back-date the technology in the car, something that goes against our principles. We prefer to advance the existing technology rather then abandon it.
Secondly, we assume you have to allow vacuum to control the turbo wastegates with different wastegate spring rates. Another thing we just don't know how to do safely without ECU control. Our GIAC datalogger monitors 600% more parameters of the ECU then a Durametric, none of which help us understand how to safely control boost.
Third...you have to make permanent and irreversible modifications to the car...cutting oil lines, etc. (see pic below). Again, can it be done, yes. Can it be reversed....for a lot of money, yes.
And finally...the main reason we stick to VTG turbos is performance. Sure, Garret turbos seems to boast higher HP output...but not much of an increase in TQ over VTG's. So real world performance just doesn't seem to show enough of an advantage to make it worthwhile. We're able to product 700 lb/ft of TQ as low as 4000 rpm's and maintain it past 7000 rpm with our 68mm VTG's. That's an incredibly broad range of power!!
Other tuners have successfully been able to run Garret turbos obviously. Hopefully one of them can chime in with some more technical information about how exactly this type of setup works.
Here's the issue we have with Garret turbos over VTG's. To be perfectly and brutally honest, there are several fundamental changes that have to be made to the foundation of the 997 Turbo in order to use Garret turbos.
For one, in order to run a Garret turbo, you have to allow the ECU to completely relinquish it's control over boost. Boost has to be controlled by an external controller, something like a GReddy profec, etc. When you do that, the boost is controlled 100% by the profec, without any input from the ECU about knock, ignition, lambda, etc. Essentially, you have to back-date the technology in the car, something that goes against our principles. We prefer to advance the existing technology rather then abandon it.
Secondly, we assume you have to allow vacuum to control the turbo wastegates with different wastegate spring rates. Another thing we just don't know how to do safely without ECU control. Our GIAC datalogger monitors 600% more parameters of the ECU then a Durametric, none of which help us understand how to safely control boost.
Third...you have to make permanent and irreversible modifications to the car...cutting oil lines, etc. (see pic below). Again, can it be done, yes. Can it be reversed....for a lot of money, yes.
And finally...the main reason we stick to VTG turbos is performance. Sure, Garret turbos seems to boast higher HP output...but not much of an increase in TQ over VTG's. So real world performance just doesn't seem to show enough of an advantage to make it worthwhile. We're able to product 700 lb/ft of TQ as low as 4000 rpm's and maintain it past 7000 rpm with our 68mm VTG's. That's an incredibly broad range of power!!
Other tuners have successfully been able to run Garret turbos obviously. Hopefully one of them can chime in with some more technical information about how exactly this type of setup works.
how about back pressure because of that?
#10
FP GT3586 turbos are not in the same area code as any VTG w/ regard to absolute performance. Problem is you need a built engine and all the other supporting mods to utilize the potential of the 3586's. But they are capable of 1100-1200whp on race fuel or E85.
#11
I agree 100% with the second part of your statement. But for me, absolute performance and horsepower are two totally different things. Because with much less HP, our VTG's are outperforming many other higher HP cars.
#12
I look forward to hearing more about your car when it's done.
#13
I just want alot of torque and that is what I am getting. I will take FT# over HP any day.
Even then my car is not a slouch. I am betting at least 875 WHP and a tq # very close to that (across a wide range of course).
Even then my car is not a slouch. I am betting at least 875 WHP and a tq # very close to that (across a wide range of course).
Last edited by Slow911TT68Tip; 07-29-2011 at 01:32 PM.
#14
I thought your car is at champion and you decide to go with vtg's?
in my opinion gt30 are much better than any vtg you can have.
this is dyno run on 6th gear and max load maha can go.
1,4 bar boost.
in my opinion gt30 are much better than any vtg you can have.
this is dyno run on 6th gear and max load maha can go.
1,4 bar boost.
#15
My Car is at Champion and given the fact I am virtually guarenteed 900 WHP++ and close to that in TQ (close to 50% of that starting at ~ 3500 RPM's) I am perfectly happy. I wonder why Porsche went with the VTG design when they could have gone elsewhere?