Capri GTT... V10, 550bhp
Discussion
I think it'll be easier for you to use the manual m3 v8 gearbox.
after taking the gearbox off the engine, you will have found a spacer that goes between the thrust bearing and the clutch fingers. that spacer wont fit the thrust bearing on the m3 'box. its reasonably easy to make one (or get one made) that fits both the m5 clutch and m3 'box though.
after taking the gearbox off the engine, you will have found a spacer that goes between the thrust bearing and the clutch fingers. that spacer wont fit the thrust bearing on the m3 'box. its reasonably easy to make one (or get one made) that fits both the m5 clutch and m3 'box though.
andygtt said:
I have the gearbox ecu and everything for it, not sure its easily or cheaply usable.
I have not stripped the controller off yet to have a look... I have read from the online 'experts' that this is neither a sequential or a conventional H pattern box and thus you can't just slap a shifter on it.
Saying that people have found ways to convert mechanically an H pattern to sequential so it can't be 'that' hard. Just depends how much force it actually takes to change the gear or hold them in gear.
What makes me think that this is the case is that BMW didn't this box as a manual in any car or iteration... instead they fitted the 6 speed from the V8 M3.
yup, the .pdf i linked on the last page confirms SMG only. Looking at the pics of the box with the mechatronics unit removed, the 4 shift pistons sit down into those cast ally shift "rods" (they are actually like concave buckets as the shift pistons drop down into them to reduce overall height). Those shift rods have cast forks dropping off them down and left/right to the bauk rings. That document also shows the gear for each rod assignment, and it's not conducive to fitting any kind of manual shifter really. If the M3 box bolts up to the engine, then that is the route too take i suspect. Alternatively you'd have to get some custom software written to operate the SMG box with a suitable rapid prototyping controller.I have not stripped the controller off yet to have a look... I have read from the online 'experts' that this is neither a sequential or a conventional H pattern box and thus you can't just slap a shifter on it.
Saying that people have found ways to convert mechanically an H pattern to sequential so it can't be 'that' hard. Just depends how much force it actually takes to change the gear or hold them in gear.
What makes me think that this is the case is that BMW didn't this box as a manual in any car or iteration... instead they fitted the 6 speed from the V8 M3.
e21Mark said:
Can't help but think a regular stick shift would suit the car better.
My Missus hated the paddle shift.... so car will be a regular stick and clutch regardless of box used.but 7 speed manual has this nice ring to it
Im not done trying... I will see if I can get the hydraulics working on it 'on the bench', then see if I can shift it and decide from there.
I was thinking very simplistically, simple H pattern set of switches:
Push into first = trigger solanoid to put into 1st
Pull out of first gear = trigger same solenoid to take into neutral
pull into second = trigger next solenoid to put into 2nd
push out of second = trigger same solenoid to put in neutral
etc etc
Maybe I am over simplifying it lol
andygtt said:
e21Mark said:
Can't help but think a regular stick shift would suit the car better.
My Missus hated the paddle shift.... so car will be a regular stick and clutch regardless of box used.but 7 speed manual has this nice ring to it
Im not done trying... I will see if I can get the hydraulics working on it 'on the bench', then see if I can shift it and decide from there.
I was thinking very simplistically, simple H pattern set of switches:
Push into first = trigger solanoid to put into 1st
Pull out of first gear = trigger same solenoid to take into neutral
pull into second = trigger next solenoid to put into 2nd
push out of second = trigger same solenoid to put in neutral
etc etc
Maybe I am over simplifying it lol
In order to change gear, the movement of the two rails needs to be simultaneous. You need to pull the current gear out of mesh and THEN push the new one home. Unfortunately, how quickly each gear meshes and un-meshes is dependant on a LOT of factors (hydraulic pressure, hydraulic oil temp, gearbox temp, torque across each gear set, how quckly the engine speed falls, and about a million other parameters. Not for nothing does the OEM set up have a rail position sensor, which is uses to close loop control (and to learn) the optimum positional control of the selector forks.
As there is no mechanical "Gate" any miss timing, or overlap, will see you in either neutral when you lift the clutch (not great) or worse, with a box full of scrap if it's selected two sets of bauks at once.
Even the control solenoids have to be "adapted" in order for the system to learn exactly how much current must be pushed through each in order to apply the correct force to the rods and hence accelerate and deccelerate them to mesh the bauks at the right moment in time.
Not for nothing were all the Gen1 SMG systems pretty hopeless! (it also worth nothing that the engine torque arbitration is handed to the transmission during a shift event, so it can control engine speed to match the new gear ratio selected.
So in summary, could you make a basic system that pushed gears back and forth, er, yes, but you'd probably not want to actually drive it anywhere, and you'd spend a lot of time either in Neutral or on the back of a tow truck......
v10 volvo build thread, maybe some ideas in here for the capri:
http://server.pure-pf.com/phpBB/viewtopic.php?f=2&...
http://server.pure-pf.com/phpBB/viewtopic.php?f=2&...
Max_Torque said:
The problem, even without the massive headache of automatically controlling the clutch (see Gen1 Vanquish for reference.....) is that the timing constraints are both very tight and highly variable!
In order to change gear, the movement of the two rails needs to be simultaneous. You need to pull the current gear out of mesh and THEN push the new one home. Unfortunately, how quickly each gear meshes and un-meshes is dependant on a LOT of factors (hydraulic pressure, hydraulic oil temp, gearbox temp, torque across each gear set, how quckly the engine speed falls, and about a million other parameters. Not for nothing does the OEM set up have a rail position sensor, which is uses to close loop control (and to learn) the optimum positional control of the selector forks.
As there is no mechanical "Gate" any miss timing, or overlap, will see you in either neutral when you lift the clutch (not great) or worse, with a box full of scrap if it's selected two sets of bauks at once.
Even the control solenoids have to be "adapted" in order for the system to learn exactly how much current must be pushed through each in order to apply the correct force to the rods and hence accelerate and deccelerate them to mesh the bauks at the right moment in time.
Not for nothing were all the Gen1 SMG systems pretty hopeless! (it also worth nothing that the engine torque arbitration is handed to the transmission during a shift event, so it can control engine speed to match the new gear ratio selected.
So in summary, could you make a basic system that pushed gears back and forth, er, yes, but you'd probably not want to actually drive it anywhere, and you'd spend a lot of time either in Neutral or on the back of a tow truck......
My first thought would be that you could implement a gate with a plate that would shift around so you could only select another gear if you were back to a neutral position i.e it would have to shift sideways to allow another gear to be selected. 6th/7th seems to be the only case where you'd go between adjacent gears but I think even there I'd have it set up to go back to a neutral backstop before the next gear. In order to change gear, the movement of the two rails needs to be simultaneous. You need to pull the current gear out of mesh and THEN push the new one home. Unfortunately, how quickly each gear meshes and un-meshes is dependant on a LOT of factors (hydraulic pressure, hydraulic oil temp, gearbox temp, torque across each gear set, how quckly the engine speed falls, and about a million other parameters. Not for nothing does the OEM set up have a rail position sensor, which is uses to close loop control (and to learn) the optimum positional control of the selector forks.
As there is no mechanical "Gate" any miss timing, or overlap, will see you in either neutral when you lift the clutch (not great) or worse, with a box full of scrap if it's selected two sets of bauks at once.
Even the control solenoids have to be "adapted" in order for the system to learn exactly how much current must be pushed through each in order to apply the correct force to the rods and hence accelerate and deccelerate them to mesh the bauks at the right moment in time.
Not for nothing were all the Gen1 SMG systems pretty hopeless! (it also worth nothing that the engine torque arbitration is handed to the transmission during a shift event, so it can control engine speed to match the new gear ratio selected.
So in summary, could you make a basic system that pushed gears back and forth, er, yes, but you'd probably not want to actually drive it anywhere, and you'd spend a lot of time either in Neutral or on the back of a tow truck......
The problem is you'd still need actuators as there's no way a mechanical linkage could manage it, nor a barrel. And the peak shift force isn't exactly low (2500N?) And the 'gate' isn't really going to make the thing fast. And you'd still need to index it. All you're really doing is avoiding the need for the controller to precisely manage the actuator timing and positions as there'd be a mechanical interlock.
The practical options are going to be a proper manual box, or to get the SMT working as originally intended. Then maybe fiddle with the control side of it to make it a bit more 'manual' feeling eg. an H-pattern shifter with Hall sensors to select the target gear. Maybe with interlock solenoids in the shifter gate to block out selections that couldn't be made for the current engine/road speed. Bit of a cheat but different from paddles.
The guys at ergen might be worth a shout
http://ergen.co.uk/
They have got the e46 SMG working as a retrofit
http://ergen.co.uk/
They have got the e46 SMG working as a retrofit
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