"Aftermarket" 5-speed
#16
Addict
Rennlist Member
Rennlist Member
DSG, PDK or whatever these new style double clutch automatic manual gearboxes are called are future. Both old style manual and automatic gearboxes will die out. Only computer controlled DSG can meet future fuel consumption targets.
#17
Racer
I would say http://www.hewland.com/svga/nlt.html
Sequential gear box for race car. Some adaptation have to be made, and it is a $20 000 project but it should work well.
Stephane
Sequential gear box for race car. Some adaptation have to be made, and it is a $20 000 project but it should work well.
Stephane
#19
I like Ryan's idea, lets assume you can fit it up, that will cost between $2 to $4K for adaption. How do you run it? That is what would be the real challenge. I like the fact that it doesn't have a torque convertor, as far as I am aware it is the part that is rev limited. 6800 rpm is the limit I have heard. When you are building a high rpm engine, mainly because of the limits of the standard gearbox. High rpm low torque to avoid breaking it.
You would need to speak to a technician regarding that gearbox, my guess it is very complex to control and would be too hard.
Greg
You would need to speak to a technician regarding that gearbox, my guess it is very complex to control and would be too hard.
Greg
#20
Edit, the AMG gearbox is only good for 7,200 rpm, also it is a pity the Ferrari gearboxes have offset input shafts. I almost bought one, super strong, bolts up to our CV shafts blah blah. Anyway wont work because of the input shaft.
Greg
Greg
#21
Drifting
Getting that Mercedes box to work would be a nightmare. 1. the engine inertia is mapped into the launch clutch. That would be all wrong. I really doubt anyone has the resources or money available to get that redone. Secondly, any new automatic transmission relies on being able to control engine torque during shifts. 928 engines don't have electronic throttles or an ECU that is torque based.
I really think you guys are wasting your time trying to adapt a new electronically controlled trans of any type.
I really think you guys are wasting your time trying to adapt a new electronically controlled trans of any type.
#22
Race Director
The PDK or BMW DCT is essentially the same thing....the box is built by Getrag and is available to anyone with the $$$ It is a wet dual clutch with 7 gears and is rated for 443ftlbs....it is HEAVY at nearly 100kg....and thats just for the trans..not the rear end!!!
I have this trans in my M3 and it is incredible....similar things are said about the PDK in P-cars...shifts far faster than any driver can and works great.....
I had a good discussion with Mark A today about the "strength" of the 928 5 speed...he brought up a good point....in his older 928's with around 400hp or less he had virtually no problems with the trans....it wasn't until his monster motor that he had problems.....and it does appear most of the 928 race car trans problems are in stroker motors with all that torque.....
There are some powerful automatics out there...but none are subjected to road course stresses...a couple perform well in open road, but thats a different story compared to road course racing.... I have been very happy with the 4 speed in the estate..but its only moving 2800lbs with 195whp-236 torque..so its hardly trying.....as reflected by its 190F max trans temps....
Hmm...maybe for the sake of arguement I should boost the estates engine to add some stress to the trans....just to see how long it can take another 100whp & torque
I have this trans in my M3 and it is incredible....similar things are said about the PDK in P-cars...shifts far faster than any driver can and works great.....
I had a good discussion with Mark A today about the "strength" of the 928 5 speed...he brought up a good point....in his older 928's with around 400hp or less he had virtually no problems with the trans....it wasn't until his monster motor that he had problems.....and it does appear most of the 928 race car trans problems are in stroker motors with all that torque.....
There are some powerful automatics out there...but none are subjected to road course stresses...a couple perform well in open road, but thats a different story compared to road course racing.... I have been very happy with the 4 speed in the estate..but its only moving 2800lbs with 195whp-236 torque..so its hardly trying.....as reflected by its 190F max trans temps....
Hmm...maybe for the sake of arguement I should boost the estates engine to add some stress to the trans....just to see how long it can take another 100whp & torque
#23
Nordschleife Master
Its interesting that most car mags are now considering the Dual clutch like the PDK, the S-tronic, MDCT and whoever else is using the dual clutch setup now as automatics. So in a sense the typical automatic is dying out in the performance segment, but I think they will always be there in your large luxobarges and so on. And the dual clutch automated manuals or manual automatics or whatever we wanna call them will remain with the more sporting variety of cars.
#24
Addict
Rennlist Member
Rennlist Member
Its interesting that most car mags are now considering the Dual clutch like the PDK, the S-tronic, MDCT and whoever else is using the dual clutch setup now as automatics. So in a sense the typical automatic is dying out in the performance segment, but I think they will always be there in your large luxobarges and so on. And the dual clutch automated manuals or manual automatics or whatever we wanna call them will remain with the more sporting variety of cars.
#25
Captain Obvious
Super User
Super User
As automatic box is longer than many manual boxes its possible to bolt some other make manual in place of automatic using automatics diff. Only real problem is at 99% of the manual boxes are designed to be bolted right after engine and thus they have large bellhousing for clutch. This will not fit into stock 928 body. Basically its either remove rear seats or make custom casing for what ever box one wants to use. Everything else is just raw work.
#26
I had a CL600 bi-turbo tuned by Renntech. It had around 800 lb-ft of tq with a conservative tune for pump gas. The Mercedes tranny was good to around 1,000 lb-ft.
#27
Captain Obvious
Super User
Super User