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Do you have more pictures of engine out of the car without the image being cut off? Looking specifically at the vacuum routing for the 997TT intake manifolds/inlets. I've got the same parts going in mine.
Originally Posted by pete95zhn
Specs:
-front and rear subframes are machined to RSR specs (=lower)
I'm assuming you use 996 cup wheel carrier/uprights? or were you able to use 996 RS or 997 GT3 ones? How much was machined and where? Is the only difference in the subframes on the 996RS/RSR that they sit higher up in the body? Very interested in this because for a while I was searching for RS uprights and subframes and couldn't find the differences in the subframes.
Most Motronic managed engines with drive by wire have programmable clusters. But you are right, it has to be cracked. Most likely anyone with the ability to correct a cluster's mileage to match you car for a cluster change has the tools to change other parameters. And can for instance be programmed over to a GT2 for instance. Just have to find the guru.
The guy we use is brilliant and has unlocked many features on the various porsche clusters but PSM and fuel tank has eluded him. I had him working on those items a few years back but to no avail. With enough time and energy spent anything can be done but the market for this is too small to justify the expense. Currently, a non PSM cluster is the only way to do it if you want to avoid the nuisance warning from recurring every 30 min.
Seriously awesome build. Congrats Do you have more pictures of engine out of the car without the image being cut off? Looking specifically at the vacuum routing for the 997TT intake manifolds/inlets. I've got the same parts going in mine.I'm assuming you use 996 cup wheel carrier/uprights? or were you able to use 996 RS or 997 GT3 ones? How much was machined and where? Is the only difference in the subframes on the 996RS/RSR that they sit higher up in the body? Very interested in this because for a while I was searching for RS uprights and subframes and couldn't find the differences in the subframes.
Here is an awesome thread going over subframe differences..
The guy we use is brilliant and has unlocked many features on the various porsche clusters but PSM and fuel tank has eluded him. I had him working on those items a few years back but to no avail. With enough time and energy spent anything can be done but the market for this is too small to justify the expense. Currently, a non PSM cluster is the only way to do it if you want to avoid the nuisance warning from recurring every 30 min.
This guy seemed to crack some of the 996 and 986 code. Even though they are not the same, the circuit architecture must be pretty similar.
The guy we use is brilliant and has unlocked many features on the various porsche clusters but PSM and fuel tank has eluded him. I had him working on those items a few years back but to no avail. With enough time and energy spent anything can be done but the market for this is too small to justify the expense. Currently, a non PSM cluster is the only way to do it if you want to avoid the nuisance warning from recurring every 30 min.
John, I have an idea that I think will solve this for us, but I need your help. I managed to pull some information on the canbus for the PSM, or atleast I can now activate an LED on the motec dash when I turn the PSM on and off. My idea is to use the motec to send a Canbus message to the dash that replicates the message sent by the PSM. The dash would then read that and in theory not flash up an error.
I know the address of the PSM signal on the canbus, but I need help on what the actually raw message is. Would you contact be able to help with that.
John, I have an idea that I think will solve this for us, but I need your help. I managed to pull some information on the canbus for the PSM, or atleast I can now activate an LED on the motec dash when I turn the PSM on and off. My idea is to use the motec to send a Canbus message to the dash that replicates the message sent by the PSM. The dash would then read that and in theory not flash up an error.
I know the address of the PSM signal on the canbus, but I need help on what the actually raw message is. Would you contact be able to help with that.
The problem I see is that if you fool the dash into thinking that PSM is functional (to keep the nuisance lights out while the pump is shut off), it will still command the throttle to be retarded as part of its protocol because it thinks all is hunky dory with PSM. As such you will only be shutting off the "rear brake pulsing" part PSM while the throttle retardation will still be active. PSM has several facets to it besides just the pump. There is also the yaw sensor. The dash has to "know" there is a fault somewhere in the PSM system (which trips the warnings) and then IT SHUTS OFF ALL OUTPUTS which includes throttle retardation.
The problem I see is that if you fool the dash into thinking that PSM is functional (to keep the nuisance lights out while the pump is shut off), it will still command the throttle to be retarded as part of its protocol because it thinks all is hunky dory with PSM. As such you will only be shutting off the "rear brake pulsing" part PSM while the throttle retardation will still be active. PSM has several facets to it besides just the pump. There is also the yaw sensor. The dash has to "know" there is a fault somewhere in the PSM system (which trips the warnings) and then IT SHUTS OFF ALL OUTPUTS which includes throttle retardation.
Without fully knowing how how the PSM is designed to work the engineer in me tends to think what would I look at to determine a car's instability? And how would I fault check the system? So maybe the issue is we are trying to power off the system instead of nulling it. Especially if the cluster cannot be programmed for another non-PSM car. If capturing the non-PSM programming parameters of a pre PSM car or GT cluster and keeping the rest is not an option it seems that nulling is the other option. Perhaps the trick is somehow nulling the yaw sensor permanently. Instead of deactivating the PSM, just trick it so it never senses the car's instability. So when the PSM is switched off or unplugged it's only tattle tale has to be the yaw sensor. That would be how the PSM knows to retard throttle and intervene even when the PSM is switched off. And if the precharge pump is unplugged now you have the cluster commanding corrective offset braking and throttle cut and the yaw sensor is not feeding back it's expected response. So the system has to have a feedback of some sort to tell the PSM that intervention is functioning. If the cluster was just happy seeing the precharge pump not shorted or open(or other known good resistive or current condition) and the same for the yaw sensor we could fool it with resistors or zener diodes.
Without fully knowing how how the PSM is designed to work the engineer in me tends to think what would I look at to determine a car's instability? And how would I fault check the system? So maybe the issue is we are trying to power off the system instead of nulling it. Especially if the cluster cannot be programmed for another non-PSM car. If capturing the non-PSM programming parameters of a pre PSM car or GT cluster and keeping the rest is not an option it seems that nulling is the other option. Perhaps the trick is somehow nulling the yaw sensor permanently. Instead of deactivating the PSM, just trick it so it never senses the car's instability. So when the PSM is switched off or unplugged it's only tattle tale has to be the yaw sensor. That would be how the PSM knows to retard throttle and intervene even when the PSM is switched off. And if the precharge pump is unplugged now you have the cluster commanding corrective offset braking and throttle cut and the yaw sensor is not feeding back it's expected response. So the system has to have a feedback of some sort to tell the PSM that intervention is functioning. If the cluster was just happy seeing the precharge pump not shorted or open(or other known good resistive or current condition) and the same for the yaw sensor we could fool it with resistors or zener diodes.
Lots of unknowns and trial and error here. I'm pretty sure the system is smarter to be simply tricked by a resistor. I think it's looking for certain feedback from the various components but I could be wrong. Once you start using resistors then you have no easy way of switching PSM back on and I think this is what many guys wanna be able to do. I still don't quite understand the bromance people have with PSM especially if they are a capable driver. These cars are not dangerous when set up properly. One of the biggest advantages of not having PSM is that you can run the larger 27mm master without issues. With that said, to ditch PSM in an OEM fashion as done by Porsche on the GT2/3 is rather involved and not necessarily cheap.
1. Change TT ABS module to GT2/3 module. You will need to rewire the connector as it's different. You will also need to install GT2/3 brake lines that connect to the ABS unit. There is 6 of them and they are cheap.
2. Change out the brake fluid reservoir to GT2/3 unit.
3. Remove PSM pump
4. Remove yaw angle sensor
5. Install GT2 instrument cluster
6. Install GT2 fuel tank
7. Install GT2 coolant pipes
I didn't say it was cheap. Lol. Or you can do what Pete did on his car and simply unplug the pump via a switch (this fully switches off PSM) and deal with the repetitive warnings in the dash. The PSM light is easy, you can simply remove the bulb. What's annoying is the "PSM failure drive to workshop" message in the central dash that pops up repeatedly every 30 minutes and you have to reclear it with the stalk.
My case is a little different. There are obviously no PSM components on my car and the Motorsport ABS unit I'm using is not compatible with any GT2/3/TT dash (my car has a GT2 dash). I have the ABS wired in with my Motec dash where any and all failure messages of the ABS system are fully selectable, programmable, and defeatable. That's a conversation for a different day however.
Lots of unknowns and trial and error here. I'm pretty sure the system is smarter to be simply tricked by a resistor. I think it's looking for certain feedback from the various components but I could be wrong. Once you start using resistors then you have no easy way of switching PSM back on and I think this is what many guys wanna be able to do. I still don't quite understand the bromance people have with PSM especially if they are a capable driver. These cars are not dangerous when set up properly. One of the biggest advantages of not having PSM is that you can run the larger 27mm master without issues. With that said, to ditch PSM in an OEM fashion as done by Porsche on the GT2/3 is rather involved and not necessarily cheap.
1. Change TT ABS module to GT2/3 module. You will need to rewire the connector as it's different. You will also need to install GT2/3 brake lines that connect to the ABS unit. There is 6 of them and they are cheap.
2. Change out the brake fluid reservoir to GT2/3 unit.
3. Remove PSM pump
4. Remove yaw angle sensor
5. Install GT2 instrument cluster
6. Install GT2 fuel tank
7. Install GT2 coolant pipes
I didn't say it was cheap. Lol. Or you can do what Pete did on his car and simply unplug the pump via a switch (this fully switches off PSM) and deal with the repetitive warnings in the dash. The PSM light is easy, you can simply remove the bulb. What's annoying is the "PSM failure drive to workshop" message in the central dash that pops up repeatedly every 30 minutes and you have to reclear it with the stalk.
My case is a little different. There are obviously no PSM components on my car and the Motorsport ABS unit I'm using is not compatible with any GT2/3/TT dash (my car has a GT2 dash). I have the ABS wired in with my Motec dash where any and all failure messages of the ABS system are fully selectable, programmable, and defeatable. That's a conversation for a different day however.
I don't think it is as easy as a bunch of resistors. That would be trivializing it bit much.
But the only way the car can know the PSM is working or not is via yaw sensors and wheel speed. So if removing it involves a bunch of silly mods to include a fuel tank swap(lol), then I would be inclined to think that identifying and understanding what feedbacks are triggering the PSM errors. And if the PSM cares about more than just pump or yaw sensor motor resistance or current feedback, then the system has to have a positive feedback loop like wheel speed and yaw angle. Maybe even steering wheel angle. So if the yaw sensor is feeding a signal that is being used to verify that the system is functional and the car is stable, then that is most likely a DC variable voltage where +/- X volts = a yaw angle or rate. Then that is a signal where you simply identify the normal 0 lateral G state voltage and feed that continuously to the cluster. Then if wheel speed(relative to one another) is also used, then that would have to be dealt with.
I don't think it is as easy as a bunch of resistors. That would be trivializing it bit much.
But the only way the car can know the PSM is working or not is via yaw sensors and wheel speed. So if removing it involves a bunch of silly mods to include a fuel tank swap(lol), then I would be inclined to think that identifying and understanding what feedbacks are triggering the PSM errors. And if the PSM cares about more than just pump or yaw sensor motor resistance or current feedback, then the system has to have a positive feedback loop like wheel speed and yaw angle. Maybe even steering wheel angle. So if the yaw sensor is feeding a signal that is being used to verify that the system is functional and the car is stable, then that is most likely a DC variable voltage where +/- X volts = a yaw angle or rate. Then that is a signal where you simply identify the normal 0 lateral G state voltage and feed that continuously to the cluster. Then if wheel speed(relative to one another) is also used, then that would have to be dealt with.
The PSM control module receives input from all 4 wheel speed sensors, yaw sensor, steering angle sensor, parking brake contact sensor, brake reservoir, brake pressure sensor, diagnostics port, PSM button, instrument cluster, and stop light switch.
It has outputs going to the PSM pump control relays, engine control module, the HVAC control module (weird..) and the diagnostics port.
Do you have more pictures of engine out of the car without the image being cut off? Looking specifically at the vacuum routing for the 997TT intake manifolds/inlets. I've got the same parts going in mine.
I might have, hold on a while. EDIT: Actually, I only have three lines there, because brake booster has electric vacuum pump at front. So one line comes from oil sump, one small line goes for all vacuum/boost and is split under the plenum and one bigger line is for fuel tank vent. It's valve is ziptied to the bar that keeps plenum's halves together.
Originally Posted by SeattleTurbo
I'm assuming you use 996 cup wheel carrier/uprights? or were you able to use 996 RS or 997 GT3 ones? How much was machined and where? Is the only difference in the subframes on the 996RS/RSR that they sit higher up in the body? Very interested in this because for a while I was searching for RS uprights and subframes and couldn't find the differences in the subframes.
You got link to Earl's pics, so nothing to add. I still have street GT3's uprights F&R with street ride height. IMO the advantage of using RS's parts with different pick-up points will come when going to those ride heights, ie 30-40 mm lower.
I still have street GT3's uprights F&R with street ride height. IMO the advantage of using RS's parts with different pick-up points will come when going to those ride heights, ie 30-40 mm lower.
From what I am reading and seeing it appears as though the 997 GT3 street,CUP,RSR and RS all have the same upright geometry and pickoff points with brake attachment and ABS being the main differences. And they all pretty much mirror the 996 RS and RSR spindles. But the subframes are different to change attach point distances relative to the body for lower ride height geometry. So if these observations are true and also taking into account that the 997 GT3 street has pretty much the same RS style upright and very similar subframes(relative to attach points for control arms) to the 996 then the uprights may have improvements not just with the lower ride height geometry. And the 996 GT3 street and cup front upright is just a C2 casting with different brake attach points.
From what I am reading and seeing it appears as though the 997 GT3 street,CUP,RSR and RS all have the same upright geometry and pickoff points with brake attachment and ABS being the main differences. And they all pretty much mirror the 996 RS and RSR spindles. But the subframes are different to change attach point distances relative to the body for lower ride height geometry. So if these observations are true and also taking into account that the 997 GT3 street has pretty much the same RS style upright and very similar subframes(relative to attach points for control arms) to the 996 then the uprights may have improvements not just with the lower ride height geometry. And the 996 GT3 street and cup front upright is just a C2 casting with different brake attach points.
Actually I have to correct myself, I wasn't quite precise and just looked from my own standpoint. Subframes I use (2002 GT3RS, pic below) have more or less the same effect than uprights with lowered pickup points (ones you mentioned above) and adding those uprights to my car wouldn't be useful until going very low. So, it's like comparing 2002 apples to 2004 oranges...
08-29-2017, 03:42 PM
