AMG Auto internals question
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From: Germany/Bavaria/Munich
AMG Auto internals question
hi,
as I have a 4-speed auto out of my 87' s4 lying around in my garage that needs some overhauling I remembered that there is also a amg kit existing.
I don't want to use org. Porsche parts if there is a kit capable of handling more torque and therefore have some questions:
- Has anybody reworked his auto gearbox with this kit and what were his
experiences
- How much (more) torque can it handle
- Is it a complete kit offered by DC to be ordered by any Mercedes dealer
- Does anybody have part/order numbers of the kit
- What is the price for the kit
Thanks for your feedback
Stefan
as I have a 4-speed auto out of my 87' s4 lying around in my garage that needs some overhauling I remembered that there is also a amg kit existing.
I don't want to use org. Porsche parts if there is a kit capable of handling more torque and therefore have some questions:
- Has anybody reworked his auto gearbox with this kit and what were his
experiences
- How much (more) torque can it handle
- Is it a complete kit offered by DC to be ordered by any Mercedes dealer
- Does anybody have part/order numbers of the kit
- What is the price for the kit
Thanks for your feedback
Stefan
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Hi Stefan:
This is a question you might want to ask Steve Cattaneo. He's a member here and owns a transmission shop on the East Coast. He is likely the most familiar with your question...
Viel Glück!
This is a question you might want to ask Steve Cattaneo. He's a member here and owns a transmission shop on the East Coast. He is likely the most familiar with your question...
Viel Glück!
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Joined: Sep 2004
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From: Stockton, CA
Steve Pappin from the LA area also had his 4 speed rebuilt using AMG internals.....but he sold his 928 and doesn't frequent this forum much anymore.....he quoted it as being able to handle 1000hp.....vs 5-600 for the stock transmission!
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From: Puyallup, WA
Hi Stefan,
Steve C. gave me the following advise (sorry no AMG part #'s) several years ago in preparation for my stroker build:
He lurks on the list, hopefully he'll have some additional input.
Steve C. gave me the following advise (sorry no AMG part #'s) several years ago in preparation for my stroker build:
Your A 28. Transmission can handle the increased torque of a
supercharger or turbo.
An external transmission cooler will extend the life of the transmission,
euro 928s have an external cooler mounted in the front grill, ran in series
with the radiator. Maybe you can find one, if not there are other coolers
you can use. I would also use synthetic transmission fluid, less
friction, cooler operating tempeture. If the transmission is being rebuilt
make sure the updated B2 servo piston is installed, part# MB A107 270 0432
and bushing # 126 277 0850,as an added benefit install a shift kit PART #
55C011, and accumulator ring kit K55301DT you cane buy them from transtar
parts phone # 1 800 932 6699.
Disable the rear pump, in the transmission, its only purpose is to push
start your car. It has a history of failure.
All of these modifications, will increase the holding capacity of the
clutches and bands. Then you can fine-tune the shift with modulator and
cable adjustments.
supercharger or turbo.
An external transmission cooler will extend the life of the transmission,
euro 928s have an external cooler mounted in the front grill, ran in series
with the radiator. Maybe you can find one, if not there are other coolers
you can use. I would also use synthetic transmission fluid, less
friction, cooler operating tempeture. If the transmission is being rebuilt
make sure the updated B2 servo piston is installed, part# MB A107 270 0432
and bushing # 126 277 0850,as an added benefit install a shift kit PART #
55C011, and accumulator ring kit K55301DT you cane buy them from transtar
parts phone # 1 800 932 6699.
Disable the rear pump, in the transmission, its only purpose is to push
start your car. It has a history of failure.
All of these modifications, will increase the holding capacity of the
clutches and bands. Then you can fine-tune the shift with modulator and
cable adjustments.
Thread Starter
Instructor
Joined: Mar 2004
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From: Germany/Bavaria/Munich
Hi@all,
thanks for the input.
Hopefully Steve C. is reading this thread
BTW:
In the german pff-forum (Nicole surely is aware of it) is a thread posted at the moment, where a 928 GT driver is looking for a possibility of cooling his gearbox via an external cooler to avoid overheating.
Any ideas from somebody on this?
thanks for the input.
Hopefully Steve C. is reading this thread
BTW:
In the german pff-forum (Nicole surely is aware of it) is a thread posted at the moment, where a 928 GT driver is looking for a possibility of cooling his gearbox via an external cooler to avoid overheating.
Any ideas from somebody on this?
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From: Helsinki, Finland
Originally Posted by srupp1969
In the german pff-forum (Nicole surely is aware of it) is a thread posted at the moment, where a 928 GT driver is looking for a possibility of cooling his gearbox via an external cooler to avoid overheating.
Any ideas from somebody on this?
Any ideas from somebody on this?
In any case I think its more important to cool differential oil than spray cooled oil into gears. If oil is pumped to gears its better to pump it different position than what was done in GTS gearbox. Some have sprayed it to upper gears when in factory version its directed directly between meshing gear pairs. IIRR there should be something in archives about one GT gearbox which has aftermarket pump system installed.
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From: Up Nort
What is the estimated limit of the Mercedes auto? Todd has yet to have transmission problems, even after 24psi on a 5 liter, 15psi on a 6.1 liter and every other combination he's tried. He is running a stock 1990 auto with the PSD hooked up to a manual control to lock up the diff.
Just curious - Todd has yet to run his car on the dyno with any configuration. That will change very soon with his latest engine.
Just curious - Todd has yet to run his car on the dyno with any configuration. That will change very soon with his latest engine.
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From: Berkshire. 'Old' England. U.K.
Originally Posted by srupp1969
In the german pff-forum (Nicole surely is aware of it) is a thread posted at the moment, where a 928 GT driver is looking for a possibility of cooling his gearbox via an external cooler to avoid overheating.
Any ideas from somebody on this?
These are pics of a cooler fitted to a GT g/box . The pump was an electric water pump (marked 'wasser', it was German). I hope they help.
In & out fittings on g/box
cooler,pump & oil lines. The cooler was mounted just behind the rear PU.
Thread Starter
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Joined: Mar 2004
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From: Germany/Bavaria/Munich
Hi Martin, thanks a lot for this info.
I have forwarded it to Bernd (nick: BB928GT)in the pff-Forum (www.pff-forum.de) and I think this might be very helpful for his planning.
@vilhuer,
also thanks for that info. It looks like if Bernd has also thought in this direction, but it is as you also mentioned a question of budget.
Cheers
Stefan
I have forwarded it to Bernd (nick: BB928GT)in the pff-Forum (www.pff-forum.de) and I think this might be very helpful for his planning.
@vilhuer,
also thanks for that info. It looks like if Bernd has also thought in this direction, but it is as you also mentioned a question of budget.
Cheers
Stefan
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From: Muenchen (Munich), Germany
custom oil cooling for GT gear box
Martin, thanks a lot for the pictures.
In this solution the oil is taken from the gear end of the gear box rather than from the differential end.
On a sketch of the gear box that I have in front of me, one can get the impression that the manual gear box has two oil sumps. One under the gears and another under the differential. Even on the photos above it looks a though.
=> Is that true (two sumps) and is it possible to pick up the oil on the gear box's rear end (in the PET I can see outlets on the rear side that could be used for that).
As Erkka I also suspect it is rahter important to cool the differential. The temperatur problems I have encountered with my gear box (a '91 GT version) also second that assumption.
Regards,
Bernd
In this solution the oil is taken from the gear end of the gear box rather than from the differential end.
On a sketch of the gear box that I have in front of me, one can get the impression that the manual gear box has two oil sumps. One under the gears and another under the differential. Even on the photos above it looks a though.
=> Is that true (two sumps) and is it possible to pick up the oil on the gear box's rear end (in the PET I can see outlets on the rear side that could be used for that).
As Erkka I also suspect it is rahter important to cool the differential. The temperatur problems I have encountered with my gear box (a '91 GT version) also second that assumption.
Regards,
Bernd
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From: Helsinki, Finland
There are two sumps (gearbox side and differential side) in all 928 manual gearboxes but they are connected about level where oil surface is. So in that regard it doesn't matter what end pickup is and where oil is pumped back in. Surfaces will even out on their own.
If I was planning on cheap pump system into late style GT gearbox I would look into how much GTS parts cost and install only pump and cooler at rear end, not entire system all the way to front. I wouldn't bother installing spray bay to cool gearbox side. Instead would just put oil back into box from differential fillup plug or slightly above it. So all that would be needed is GTS gearbox rear cover, oil pump plus its running gear on differential side, check valve in the cover and banjo bolt on top to take oil to cooler from Porsche and custom oil cooler mounted inside rear bumper and few self made oil lines.
This is factory setup in GTS gearbox. Spray bar has different size holes in it, one hole for each gear. They grow in size further back the bar ending to largest hole in the end which points to backside of differential gear. Besides these there are few parts which purpose is to collect and feed oil into pinion bearing.
This is differential side of earlier ('85 in this case but all years up to '91 are same) gearbox. Bearing support would get in the way of the spray.
More complex home made version in older box.
http://members.rennlist.com/pageauto/transmission.htm
If I was planning on cheap pump system into late style GT gearbox I would look into how much GTS parts cost and install only pump and cooler at rear end, not entire system all the way to front. I wouldn't bother installing spray bay to cool gearbox side. Instead would just put oil back into box from differential fillup plug or slightly above it. So all that would be needed is GTS gearbox rear cover, oil pump plus its running gear on differential side, check valve in the cover and banjo bolt on top to take oil to cooler from Porsche and custom oil cooler mounted inside rear bumper and few self made oil lines.
This is factory setup in GTS gearbox. Spray bar has different size holes in it, one hole for each gear. They grow in size further back the bar ending to largest hole in the end which points to backside of differential gear. Besides these there are few parts which purpose is to collect and feed oil into pinion bearing.
This is differential side of earlier ('85 in this case but all years up to '91 are same) gearbox. Bearing support would get in the way of the spray.
More complex home made version in older box.
http://members.rennlist.com/pageauto/transmission.htm
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From: Helsinki, Finland
Originally Posted by heinrich
Some of us aren't so blessed that we have GTS boxes, we have regular old S4 gearboxes 
