Need advice-993TT transmission in 964 C4
12-28-2002, 01:55 PM
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hallo
The 964 uses a hydraulic system for the 4WD ,managed with the Brakecomputer and Valves .
The 993 has a different System and the Brakeelectronics are not involved . There are no hydraulic Components on the Tranny besides the Clutchslave .
The 993 also has a different axletube and Frontdifferential .You can change the Complete Unit, with the Gearbox, TorqueTube and Frontdiff,and disconnect the hydraulic to the Trans .There are also different Gearings in the Frontdiff.
harald
The 964 uses a hydraulic system for the 4WD ,managed with the Brakecomputer and Valves .
The 993 has a different System and the Brakeelectronics are not involved . There are no hydraulic Components on the Tranny besides the Clutchslave .
The 993 also has a different axletube and Frontdifferential .You can change the Complete Unit, with the Gearbox, TorqueTube and Frontdiff,and disconnect the hydraulic to the Trans .There are also different Gearings in the Frontdiff.
harald
12-28-2002, 07:36 PM
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Thank you Harald
I'm planing to replace the Complete Unit, Gearbox TorqueTube and Frontdiff, what kind of front axles do I need the originals?
How do I disconnect the hydraulic to the Trans without hurting the ABS?
Thanks Tal
I'm planing to replace the Complete Unit, Gearbox TorqueTube and Frontdiff, what kind of front axles do I need the originals?
How do I disconnect the hydraulic to the Trans without hurting the ABS?
Thanks Tal
12-29-2002, 03:17 PM
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The 964 has a 100% mechanical AWD system. There is no control over the AWD system. The traction control system (PDAS) is hydraulically actuated (just like the clutch) and electronically controlled. There is I repeat, NO control over the AWD system what so ever. The traction control uses the AWD system but the AWD does not use or need the traction control.
The 993 uses a viscous coupling (ala Subaru) to link the front with the rear. Normal drive is 5% front and 95% rear.
The traction control of the 964 can be disconnected and have no affect on the AWD system what so ever. You cannot make a C4 into a C2 unless you remove the driveshaft and torque tube assembly which links the power transfer unit to the front differential. Mind you you will dump your gearbox and diff oil contents all over the floor if you do.
The 964 AWD system is permanent and fixed at 31% front and 69% rear. The traction control system provides a method to torque transfer front to rear and rear to front.
Ciao,
Adrian
911C4
PS: The mechanical section of the traction control differential locks are mounted in the transmission housing. One in the power transfer unit and one in the rear differential. However these units are NOT required for AWD operation. You cannot disconnect the traction control system and retain the ABS. One gone the other is gone with it.
The 993 uses a viscous coupling (ala Subaru) to link the front with the rear. Normal drive is 5% front and 95% rear.
The traction control of the 964 can be disconnected and have no affect on the AWD system what so ever. You cannot make a C4 into a C2 unless you remove the driveshaft and torque tube assembly which links the power transfer unit to the front differential. Mind you you will dump your gearbox and diff oil contents all over the floor if you do.
The 964 AWD system is permanent and fixed at 31% front and 69% rear. The traction control system provides a method to torque transfer front to rear and rear to front.
Ciao,
Adrian
911C4
PS: The mechanical section of the traction control differential locks are mounted in the transmission housing. One in the power transfer unit and one in the rear differential. However these units are NOT required for AWD operation. You cannot disconnect the traction control system and retain the ABS. One gone the other is gone with it.
12-29-2002, 03:39 PM
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I suppose I had better answer your question as well Taly. Would be nice if you identified yourself as well because this forum is to help the individual, I assume that you are a genuine individual seeking advice.
This conversion has been done before.
Almost nothing of the G64 transmission system including the Bosch PDAS/ABS system will remain. Maybe a few fittings. The axles cannot be used either. The 993TT axles are a tad beefier.
The existing electronics and hydraulic system would also have to be removed and replaced with the Bosch 5.2.1 system installed in the 993TT.
Tech 9 a company in the UK run by Phil Hindley I know have done this conversion. Mating the transmission to the engine is no problem I believe. I also know of a C4 here in Europe (in Germany actually) fitted with a full 993TT engine and transmission. I have no idea why but they recently tried to sell it for more than what you would pay for a 993TT.
I will not ask why but may I suggest that you consider a 993 C4. I reckon it would save you a lot of money.
If not then good luck and be nice to your bank manager. Have you considered installing the Paris-Dakar transmission.
Ciao,
Adrian
911C4
This conversion has been done before.
Almost nothing of the G64 transmission system including the Bosch PDAS/ABS system will remain. Maybe a few fittings. The axles cannot be used either. The 993TT axles are a tad beefier.
The existing electronics and hydraulic system would also have to be removed and replaced with the Bosch 5.2.1 system installed in the 993TT.
Tech 9 a company in the UK run by Phil Hindley I know have done this conversion. Mating the transmission to the engine is no problem I believe. I also know of a C4 here in Europe (in Germany actually) fitted with a full 993TT engine and transmission. I have no idea why but they recently tried to sell it for more than what you would pay for a 993TT.
I will not ask why but may I suggest that you consider a 993 C4. I reckon it would save you a lot of money.
If not then good luck and be nice to your bank manager. Have you considered installing the Paris-Dakar transmission.
Ciao,
Adrian
911C4
12-29-2002, 04:48 PM
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hallo Adrian
Why would you change the elektronics if the AWD is fully mechanical ?
The Frontaxles are a little longer in the 993 and the ABS Gearring is different,so you need the 993
Axles and use the 964 Joint on the Wheelside .
You can just plug the Hydraulicline for the Gearbox.
I have put a 6 Speed Gearbox in a 964 C4 and used the 964 Frontdiff Z 64/00 , it has a 31:9 Gearing .This was a 993 C4 not Turbotrans .
The Operation is a pretty good mess with the Hydraulic Fluid and Oil running all over the Place and yourself .
The Question was if it is possible ,and i would say yes it is .
harald
Why would you change the elektronics if the AWD is fully mechanical ?
The Frontaxles are a little longer in the 993 and the ABS Gearring is different,so you need the 993
Axles and use the 964 Joint on the Wheelside .
You can just plug the Hydraulicline for the Gearbox.
I have put a 6 Speed Gearbox in a 964 C4 and used the 964 Frontdiff Z 64/00 , it has a 31:9 Gearing .This was a 993 C4 not Turbotrans .
The Operation is a pretty good mess with the Hydraulic Fluid and Oil running all over the Place and yourself .
The Question was if it is possible ,and i would say yes it is .
harald
12-30-2002, 12:28 AM
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Thank you Adrian and Harald
I'm replacing my 964 C4 engine with a used 993TT engine, as part of the deal I bought the 993TT transmission and now I have to decide which is the best way to go, the two key parameters are the installation complexity and performance and handling.
PDFD-Porsche Dynamic Four-wheel Drive, this isn't permanent and fixed AWD system, the power distribution between front and rear changes according to the difference in the rotation speeds of the wheels and the longitudinal and transverse accelerations.
I still need your help please advise me which is a better AWD system 993TT system or 964 C4 system, please focus on two parameters, technical reliability, I'm planing on 600HP, and performance and handling.
Thanks Tal
I'm replacing my 964 C4 engine with a used 993TT engine, as part of the deal I bought the 993TT transmission and now I have to decide which is the best way to go, the two key parameters are the installation complexity and performance and handling.
PDFD-Porsche Dynamic Four-wheel Drive, this isn't permanent and fixed AWD system, the power distribution between front and rear changes according to the difference in the rotation speeds of the wheels and the longitudinal and transverse accelerations.
I still need your help please advise me which is a better AWD system 993TT system or 964 C4 system, please focus on two parameters, technical reliability, I'm planing on 600HP, and performance and handling.
Thanks Tal
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12-30-2002, 12:22 PM
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Dear Harold,
Firstly let me invite you to a technical session that will be arranged in the USA for next year. I know the G64 transmission in my sleep and I intend to share this knowledge. We will strip piece by piece the G64 transmission clearly showing how everything is purely mechanical. I even drove an entire winter without the PDAS/ABS control unit installed and a diff lock hydraulic actuator failed. The centre differential lock. No ABS either.
Why you change the electronics? is VERY simple to answer. The PDAS/ABS control unit has a function installed which is a system intelock control. If you disconnect the diff locks so they cannot work completely the PDAS or traction control unit will detect their failure and fail itself. It will due to the interlock system fail the ABS system.
I would change the electronics in order to restore my ABS function. This would require re-wiring.
The 993TT uses a 3 wheel speed sensor system. The 964 uses a 4 wheel speed sensor system.
I would also love to see on paper how you managed to install a totally different transmission system into a 964 C4 and retained the traction control system and the ABS system.
I stated in my second post that this is type of conversion is possible. It has been done. It is a huge and complex job and should not be undertaken lightly.
Personally I believe the 993TT system belongs in a 993 not in a 964 however that is the choice of the individual.
Now Tal to answer your last parameter. Actually I already have. The 993 suspension handles better than the 964. There was never a 964 sent out of the factory with 600 HP. The 993 came closer with the GT-2 and the EVO II GT-2. As I said I would carry out the installation on a 993 not a 964. The most powerful 964 I have seen is the Pikes Peak 500 hp TT conversion.
Ciao,
Adrian
911C4
Firstly let me invite you to a technical session that will be arranged in the USA for next year. I know the G64 transmission in my sleep and I intend to share this knowledge. We will strip piece by piece the G64 transmission clearly showing how everything is purely mechanical. I even drove an entire winter without the PDAS/ABS control unit installed and a diff lock hydraulic actuator failed. The centre differential lock. No ABS either.
Why you change the electronics? is VERY simple to answer. The PDAS/ABS control unit has a function installed which is a system intelock control. If you disconnect the diff locks so they cannot work completely the PDAS or traction control unit will detect their failure and fail itself. It will due to the interlock system fail the ABS system.
I would change the electronics in order to restore my ABS function. This would require re-wiring.
The 993TT uses a 3 wheel speed sensor system. The 964 uses a 4 wheel speed sensor system.
I would also love to see on paper how you managed to install a totally different transmission system into a 964 C4 and retained the traction control system and the ABS system.
I stated in my second post that this is type of conversion is possible. It has been done. It is a huge and complex job and should not be undertaken lightly.
Personally I believe the 993TT system belongs in a 993 not in a 964 however that is the choice of the individual.
Now Tal to answer your last parameter. Actually I already have. The 993 suspension handles better than the 964. There was never a 964 sent out of the factory with 600 HP. The 993 came closer with the GT-2 and the EVO II GT-2. As I said I would carry out the installation on a 993 not a 964. The most powerful 964 I have seen is the Pikes Peak 500 hp TT conversion.
Ciao,
Adrian
911C4
12-30-2002, 02:56 PM
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hallo Taly
If you have enough Power ( obvious ) go with the
964 AWD system ,it is by far superior over the 993
and was only dropped for Cost and weight reasons .
To put in the 993 System takes a lot of Time and Money and if you can live with the 5 Speed and Gearing of the C4 that is the way to go .Top speed is not as high but acceleration is awesome .
harald
If you have enough Power ( obvious ) go with the
964 AWD system ,it is by far superior over the 993
and was only dropped for Cost and weight reasons .
To put in the 993 System takes a lot of Time and Money and if you can live with the 5 Speed and Gearing of the C4 that is the way to go .Top speed is not as high but acceleration is awesome .
harald
12-30-2002, 10:22 PM
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Thanks Harald
In his book Bruce Anderson wrote "This system (993 C4) was much more transparent than the overly complicated computer controlled system previously used, which always induced understeer and made the car feel as though it was front-wheel drive."
From what I understand the opinion is split on this issue.
Are you looking for used 993TT transmission?
Thanks Tal
In his book Bruce Anderson wrote "This system (993 C4) was much more transparent than the overly complicated computer controlled system previously used, which always induced understeer and made the car feel as though it was front-wheel drive."
From what I understand the opinion is split on this issue.
Are you looking for used 993TT transmission?
Thanks Tal
12-30-2002, 10:32 PM
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[quote]Originally posted by taly911:
<strong>Thanks Harald
In his book Bruce Anderson wrote "This system (993 C4) was much more transparent than the overly complicated computer controlled system previously used, which always induced understeer and made the car feel as though it was front-wheel drive."
From what I understand the opinion is split on this issue.
Are you looking for used 993TT transmission?
Thanks Tal</strong><hr></blockquote>
OT (kind of) but has Bruce Anderson <img src="graemlins/sleep.gif" border="0" alt="[sleep]" /> <img src="graemlins/sleep.gif" border="0" alt="[sleep]" /> <img src="graemlins/sleep.gif" border="0" alt="[sleep]" /> ever written a good word about the 964? All I see are repeated negative comments(and I mean repeated in the literal sense of the word - the guy seems to regurgitate the same stuff year in year out).
<img src="graemlins/soapbox.gif" border="0" alt="[soapbox]" /> <img src="graemlins/soapbox.gif" border="0" alt="[soapbox]" />
<strong>Thanks Harald
In his book Bruce Anderson wrote "This system (993 C4) was much more transparent than the overly complicated computer controlled system previously used, which always induced understeer and made the car feel as though it was front-wheel drive."
From what I understand the opinion is split on this issue.
Are you looking for used 993TT transmission?
Thanks Tal</strong><hr></blockquote>
OT (kind of) but has Bruce Anderson <img src="graemlins/sleep.gif" border="0" alt="[sleep]" /> <img src="graemlins/sleep.gif" border="0" alt="[sleep]" /> <img src="graemlins/sleep.gif" border="0" alt="[sleep]" /> ever written a good word about the 964? All I see are repeated negative comments(and I mean repeated in the literal sense of the word - the guy seems to regurgitate the same stuff year in year out).
<img src="graemlins/soapbox.gif" border="0" alt="[soapbox]" /> <img src="graemlins/soapbox.gif" border="0" alt="[soapbox]" />
12-31-2002, 11:19 AM
#12
Ruairidh:
Bruce has gotten better in the recent past on his views of the 964. Years ago (if I remember correctly), he used to call the 964 the "ugly duckling" of the 911 world. Now he's warmed up to the model and lately has even called the 964 a bargin and has written that the late 964's are very good cars. He mentions the early 964's can be good cars (value wise) if they are in good condition.
So, it seems he still favors the earlier cars and the 993 over the 964. But it's not as bad as it used to be. That's good for us 964 owners and our resale values!
Jay
90 964
Bruce has gotten better in the recent past on his views of the 964. Years ago (if I remember correctly), he used to call the 964 the "ugly duckling" of the 911 world. Now he's warmed up to the model and lately has even called the 964 a bargin and has written that the late 964's are very good cars. He mentions the early 964's can be good cars (value wise) if they are in good condition.
So, it seems he still favors the earlier cars and the 993 over the 964. But it's not as bad as it used to be. That's good for us 964 owners and our resale values!
Jay
90 964
01-04-2003, 04:25 AM
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Sorry for my delay in posting but I was having some access problems for the past couple of days.
Anyway to answer questions.
More posts after my last one. Please stop getting the AWD system and the traction control systems mixed up. Secondly comparing the 964 system with the 993 system as quoted from a book is like comparing apples and oranges. The 964 system is an AWD system the 993 is more of an elaborate front to rear traction control system.
Now to the tech session. If we can get things organised we will run the session at the Bentley facility in Cambridge Mass. When etc is all to be worked out. The plan is to get hold of a complete AWD system, connect it up and show everybody that it is mechanical then disassemble from the front and move backwards.
It will be a team effort to ensure those attending get the full picture.
To Johns question on the transmission.
Which G50 gearbox. There were a number of them. If I was going to bolt on 450 HP I would be using a G50/10 or G50/52 gearbox. The standard G50/03/04/05 I am not sure can take the load. The highest factory output in the 964 series were the 964 Turbo 3.6S with 385HP and G50/52 gearboxe.
Ciao,
Adrian
911C4
Anyway to answer questions.
More posts after my last one. Please stop getting the AWD system and the traction control systems mixed up. Secondly comparing the 964 system with the 993 system as quoted from a book is like comparing apples and oranges. The 964 system is an AWD system the 993 is more of an elaborate front to rear traction control system.
Now to the tech session. If we can get things organised we will run the session at the Bentley facility in Cambridge Mass. When etc is all to be worked out. The plan is to get hold of a complete AWD system, connect it up and show everybody that it is mechanical then disassemble from the front and move backwards.
It will be a team effort to ensure those attending get the full picture.
To Johns question on the transmission.
Which G50 gearbox. There were a number of them. If I was going to bolt on 450 HP I would be using a G50/10 or G50/52 gearbox. The standard G50/03/04/05 I am not sure can take the load. The highest factory output in the 964 series were the 964 Turbo 3.6S with 385HP and G50/52 gearboxe.
Ciao,
Adrian
911C4
