RWD Turbo= BEAST
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Question for you: So when I removed my front diff, axles, & drive shaft. my car immediately threw a PTM error code. Driving the car on the street aggressively, all seemed fine other than I noticed I could only make 15psi of boost and whenever I would select the Sport mode to allow over boost it would not allow it to happen due to the PTM code.
Are you able to select Sport Mode and make 21-23psi?
Now when I took the car to the track (road course) that's when things “electronically” were very unhappy, and the car was almost undrivable by my standards. Keep in mind, hard launching from stop lights still was a hoot, it would even break lose in third gear and get a little sideways. I just wonder how your set-up would work when driven hard and a wheel leaves the ground, or the entire front end gets light. Will the electronics take over and chop your throttle?
If you ever get on track please let us know your finds.
Thanks.
Are you able to select Sport Mode and make 21-23psi?
Now when I took the car to the track (road course) that's when things “electronically” were very unhappy, and the car was almost undrivable by my standards. Keep in mind, hard launching from stop lights still was a hoot, it would even break lose in third gear and get a little sideways. I just wonder how your set-up would work when driven hard and a wheel leaves the ground, or the entire front end gets light. Will the electronics take over and chop your throttle?
If you ever get on track please let us know your finds.
Thanks.
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Question for you: So when I removed my front diff, axles, & drive shaft. my car immediately threw a PTM error code. Driving the car on the street aggressively, all seemed fine other than I noticed I could only make 15psi of boost and whenever I would select the Sport mode to allow over boost it would not allow it to happen due to the PTM code.
Are you able to select Sport Mode and make 21-23psi?
Now when I took the car to the track (road course) that's when things “electronically” were very unhappy, and the car was almost undrivable by my standards. Keep in mind, hard launching from stop lights still was a hoot, it would even break lose in third gear and get a little sideways. I just wonder how your set-up would work when driven hard and a wheel leaves the ground, or the entire front end gets light. Will the electronics take over and chop your throttle?
If you ever get on track please let us know your finds.
Thanks.
Are you able to select Sport Mode and make 21-23psi?
Now when I took the car to the track (road course) that's when things “electronically” were very unhappy, and the car was almost undrivable by my standards. Keep in mind, hard launching from stop lights still was a hoot, it would even break lose in third gear and get a little sideways. I just wonder how your set-up would work when driven hard and a wheel leaves the ground, or the entire front end gets light. Will the electronics take over and chop your throttle?
If you ever get on track please let us know your finds.
Thanks.
You have ran into this issue because you took out your axles! With your axle taken out your front wheel sensors will not work. This will cause your PSM and ABS to not function. If you want to take out the whole FWD system you need to convert it to GT2 spec. This includes the GT2 stub axle to keep you ABS and PSM functioning!
I have have not experienced any of the issues you have described above, My boost is pinned at +17psi. Again I have no codes and the ABS and PSM are functioning. In fact the PSM has already saved me a couple times since the conversion! I find the systems function as they did before the conversion.
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Thought about this as a trial for my Friday "open lapping day." In reality though, who would want a "One wheel drivetrain" at the track?
I'll drop the driveshaft and test this setup after this coming weekend to evaluate the cars weight transfer on the street. Hope I don't get a ticket doing this! I may test this at the track the Friday after if my street evaluation checks out.
I'll drop the driveshaft and test this setup after this coming weekend to evaluate the cars weight transfer on the street. Hope I don't get a ticket doing this! I may test this at the track the Friday after if my street evaluation checks out.
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^ After pulling everything out and putting GT2 axle stubs in, everything was a-okay on the street. It was when yaw, pitch, and roll factors came into play on track, (limits that are hard to find on the street) the electronics were VERY unhappy.
It will be very interesting to hear what you have to say after your track day. I get the theory behind pulling just the drive shaft, because there are two sensors wired into the front diff. If the diff sensors are still in place it could very well work on track without any issues.
We have successfully tested a different approach that works (RWD) but it comes at a price and a lot of re-programming to make things happy (in RWD). Currently we are testing a new solution which will allow us to maintain AWD but without all the complications of converting to RWD.
If just pulling the drive shaft out works...this would be the simplest and the most economical approach.
Fingers crossed for your test day!
It will be very interesting to hear what you have to say after your track day. I get the theory behind pulling just the drive shaft, because there are two sensors wired into the front diff. If the diff sensors are still in place it could very well work on track without any issues.
We have successfully tested a different approach that works (RWD) but it comes at a price and a lot of re-programming to make things happy (in RWD). Currently we are testing a new solution which will allow us to maintain AWD but without all the complications of converting to RWD.
If just pulling the drive shaft out works...this would be the simplest and the most economical approach.
Fingers crossed for your test day!
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The key to the rwd conversion is going to be for someone to figure out how to totally defeat/disable PSM/PTM and just leave the ABS functional. This is easily done on the 996 but not the 997. I suspect that installing a GT2 instrument cluster is the key. I did that in my car (996) and it no longer throws any codes because the cluster in not "looking" for a PSM signal from the ABS unit. PSM has been totally removed from my car as I'm running a PMNA Cup ABS unit. It would be interesting for someone to try plugging in the GT2 cluster to see how that would work on the 997. I think that might do it because the GT2 cluster cluster in not looking for the PTM output signal from the front diff and as such no codes would be thrown.
Last edited by pwdrhound; Oct 14, 2015 at 04:36 AM.
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Thought about this as a trial for my Friday "open lapping day." In reality though, who would want a "One wheel drivetrain" at the track?
I'll drop the driveshaft and test this setup after this coming weekend to evaluate the cars weight transfer on the street. Hope I don't get a ticket doing this! I may test this at the track the Friday after if my street evaluation checks out.
I'll drop the driveshaft and test this setup after this coming weekend to evaluate the cars weight transfer on the street. Hope I don't get a ticket doing this! I may test this at the track the Friday after if my street evaluation checks out.
Did you get around to testing this setup?
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Hi Mike, I haven't. I think I may have lost a turbo the first session last weekend. Will start tearing the car down tomorrow to find the damage.
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I feel your pain! good luck.
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I wanted to update everyone,
After a couple years of running RWD with only my front driveshaft disconnect I decided it was time to get rid of the ~100 pound FWD system. I started by taking buying GT2 stub axles from @VID997 and removed the front drive shafts, everything worked out great. However as soon as I removed the front diff I got a PTM error. With this error I was unable to put the car in sport mode or take PSM off. Well after countless hours and various Porsche specialists trying to fix this issue, we were finally able to get it done! Now I have successfully removed the front drive-train including diff and the car feels very good and extremely light!
Now according to @VID997 when the vehicle is under heavy load in a corner and a wheel lifts off the ground the PSM my have an issue. However for the past years it has ran flawlessly on the road with not a single hiccup.
The only downside to removing the front diff is that there may be a slight hint of under-steer due to the weight loss, however I believe with adjustable sway-bars I will be able to hone it in @cannga ?
After a couple years of running RWD with only my front driveshaft disconnect I decided it was time to get rid of the ~100 pound FWD system. I started by taking buying GT2 stub axles from @VID997 and removed the front drive shafts, everything worked out great. However as soon as I removed the front diff I got a PTM error. With this error I was unable to put the car in sport mode or take PSM off. Well after countless hours and various Porsche specialists trying to fix this issue, we were finally able to get it done! Now I have successfully removed the front drive-train including diff and the car feels very good and extremely light!
Now according to @VID997 when the vehicle is under heavy load in a corner and a wheel lifts off the ground the PSM my have an issue. However for the past years it has ran flawlessly on the road with not a single hiccup.
The only downside to removing the front diff is that there may be a slight hint of under-steer due to the weight loss, however I believe with adjustable sway-bars I will be able to hone it in @cannga ?
Last edited by mikestyle; Nov 10, 2022 at 03:35 PM.
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I wanted to update everyone,
After a couple years of running RWD with only my front driveshaft disconnect I decided it was time to get rid of the ~100 pound FWD system. I started by taking buying GT2 stub axles from @VID997 and removed the front drive shafts, everything worked out great. However as soon as I removed the front diff I got a PTM error. With this error I was unable to put the car in sport mode or take PSM off. Well after countless hours and various Porsche specialists trying to fix this issue, MVS Motors in Toronto was finally able to get it done! Now I have successfully removed the front drive-train including diff and the car feels very good and extremely light!
Now according to @VID997 when the vehicle is under heavy load in a corner and a wheel lifts off the ground the PSM my have an issue. However for the past years it has ran flawlessly on the road with not a single hiccup.
The only downside to removing the front diff is that there may be a slight hint of under-steer due to the weight loss, however I believe with adjustable sway-bars I will be able to hone it in @cannga ?
After a couple years of running RWD with only my front driveshaft disconnect I decided it was time to get rid of the ~100 pound FWD system. I started by taking buying GT2 stub axles from @VID997 and removed the front drive shafts, everything worked out great. However as soon as I removed the front diff I got a PTM error. With this error I was unable to put the car in sport mode or take PSM off. Well after countless hours and various Porsche specialists trying to fix this issue, MVS Motors in Toronto was finally able to get it done! Now I have successfully removed the front drive-train including diff and the car feels very good and extremely light!
Now according to @VID997 when the vehicle is under heavy load in a corner and a wheel lifts off the ground the PSM my have an issue. However for the past years it has ran flawlessly on the road with not a single hiccup.
The only downside to removing the front diff is that there may be a slight hint of under-steer due to the weight loss, however I believe with adjustable sway-bars I will be able to hone it in @cannga ?
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I wanted to update everyone,
After a couple years of running RWD with only my front driveshaft disconnect I decided it was time to get rid of the ~100 pound FWD system. I started by taking buying GT2 stub axles from @VID997 and removed the front drive shafts, everything worked out great. However as soon as I removed the front diff I got a PTM error. With this error I was unable to put the car in sport mode or take PSM off. Well after countless hours and various Porsche specialists trying to fix this issue, MVS Motors in Toronto was finally able to get it done! Now I have successfully removed the front drive-train including diff and the car feels very good and extremely light!
Now according to @VID997 when the vehicle is under heavy load in a corner and a wheel lifts off the ground the PSM my have an issue. However for the past years it has ran flawlessly on the road with not a single hiccup.
The only downside to removing the front diff is that there may be a slight hint of under-steer due to the weight loss, however I believe with adjustable sway-bars I will be able to hone it in @cannga ?
After a couple years of running RWD with only my front driveshaft disconnect I decided it was time to get rid of the ~100 pound FWD system. I started by taking buying GT2 stub axles from @VID997 and removed the front drive shafts, everything worked out great. However as soon as I removed the front diff I got a PTM error. With this error I was unable to put the car in sport mode or take PSM off. Well after countless hours and various Porsche specialists trying to fix this issue, MVS Motors in Toronto was finally able to get it done! Now I have successfully removed the front drive-train including diff and the car feels very good and extremely light!
Now according to @VID997 when the vehicle is under heavy load in a corner and a wheel lifts off the ground the PSM my have an issue. However for the past years it has ran flawlessly on the road with not a single hiccup.
The only downside to removing the front diff is that there may be a slight hint of under-steer due to the weight loss, however I believe with adjustable sway-bars I will be able to hone it in @cannga ?
thumbs up for MVS motors, these are the guys who worked on my car...turbo upgrades, many parts changed, etc...
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I wanted to update everyone,
After a couple years of running RWD with only my front driveshaft disconnect I decided it was time to get rid of the ~100 pound FWD system. I started by taking buying GT2 stub axles from @VID997 and removed the front drive shafts, everything worked out great. However as soon as I removed the front diff I got a PTM error. With this error I was unable to put the car in sport mode or take PSM off. Well after countless hours and various Porsche specialists trying to fix this issue, MVS Motors in Toronto was finally able to get it done! Now I have successfully removed the front drive-train including diff and the car feels very good and extremely light!
Now according to @VID997 when the vehicle is under heavy load in a corner and a wheel lifts off the ground the PSM my have an issue. However for the past years it has ran flawlessly on the road with not a single hiccup.
The only downside to removing the front diff is that there may be a slight hint of under-steer due to the weight loss, however I believe with adjustable sway-bars I will be able to hone it in @cannga ?
After a couple years of running RWD with only my front driveshaft disconnect I decided it was time to get rid of the ~100 pound FWD system. I started by taking buying GT2 stub axles from @VID997 and removed the front drive shafts, everything worked out great. However as soon as I removed the front diff I got a PTM error. With this error I was unable to put the car in sport mode or take PSM off. Well after countless hours and various Porsche specialists trying to fix this issue, MVS Motors in Toronto was finally able to get it done! Now I have successfully removed the front drive-train including diff and the car feels very good and extremely light!
Now according to @VID997 when the vehicle is under heavy load in a corner and a wheel lifts off the ground the PSM my have an issue. However for the past years it has ran flawlessly on the road with not a single hiccup.
The only downside to removing the front diff is that there may be a slight hint of under-steer due to the weight loss, however I believe with adjustable sway-bars I will be able to hone it in @cannga ?
In addition another thing to keep in mind is (I think) these softer settings of front suspension may adversely affect subjective steering feel (firmness, precision) and response, etc. "It's complicated."
Hope this helps and have fun.
Last edited by cannga; Jul 14, 2019 at 01:01 PM.
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Hi, I am no expert but yes, soft setting of adjustable front sway-bar, softer front spring rate, etc., should decrease understeer. Also, as you already know, changing from 4WD to 2WD has decreased understeer in your car (a 4WD car understeers).
In addition another thing to keep in mind is (I think) these softer settings of front suspension may adversely affect subjective steering feel (firmness, precision) and response, etc. "It's complicated." Hope this helps and have fun.
In addition another thing to keep in mind is (I think) these softer settings of front suspension may adversely affect subjective steering feel (firmness, precision) and response, etc. "It's complicated."
Hope this helps and have fun.
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They were able to trick the wiring harness into thinking the components are still attached. They did not get into programing, but instead worked with the two connections on the front diff. For more info I would give them a call!