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The problems with the CELs from either running race headers without cats OR the 82mm throttle body have been sorted by Cobb. I confirmed all of this last week because i had issues UNTIL i removed my post-cat O2 sensors entirely.
More importantly, as for the hanging throttle issue, ShakeNBake and 1 other are the only instances we have heard of this and i am still digging for more. I have called everyone that sells tunes and sells plenums and TB upgrades. I have since reached out again to Shake N Bake. Given that it has happened to some without a tune on their car, Cobb isn't responsible and while they're working on it, that's a request that will require a large undertaking.
If there is someone that has experienced this that we have not heard from, i would love to talk to you. I have a customer in Nebraska who has the race headers and the TB without a flash and while he has CELs, no issues downshifting on track. I was going to do a custom tune for him this week after he logged it.
To give an update, below is a dyno run from last week from my ongoing Stage II project. I went back to try every single Cobb map available as far as cam timing, ignition, flappers, etc. The car is a Stage II which is the X51 upgrade, Cargraphic race headers, a flywheel that weighs half of what the stock one does and 5 gallons of 98 octane mixed on top of 10 gallons of some bad 92 octane that was causing awful knocking. The mapping is stock Porsche mapping for a 991 X51/GTS.
As of now I am continuing with the Cobb software because it gives me the control of the mapping and allows me to custom tune ECUs for customers. The control is awesome given that i can manipulate intake flaps, lambda tuning and it has allowed me to install race manifolds without cats and have no CELs. I can make sales in the paddock and put files in peoples' hands without relying on anyone else and this is huge for us. HOWEVER, in my quest to start with the proper base file, with my own tooling I programmed my car to that of a 991 GTS. While I have a more invasive software that allows me to turn off lights on the dash that are a result of my installing X51 software, you should see what the cluster used to look like. Anyone who attempts this will have a Christmas Tree for a dash with every single possible light on. THEREFORE I have not booked a customer for this yet because the result is no PSM, no ABS, no auto blipper and conlicts for TPMS and trans temps. Given that i have been at this very task since 2014, I knew this would happen if i tried 911 mapping in a Cayman. To this day, the only way to get this mapping in a 981 ECU AND have everything function as delivered from Porsche is to send the ECU to/from Germany. Of the 4 or 5 cars we sent out ECUs for, they are the only cars i know of worldwide that operate with lights on the cluster while running the factory 991 X51 GTS mapping. When i perfect the GTS mapping and get the next level of control i will be able to transfer everything over to the GT4 mapping and that means none of you will have to worry about any of this.
I am continuing on with the Cobb folks though because they have been great to work with, they're always responsive to my questions and have always offered to help, even at their expense. Before i go further, everyone to this date has also provided the same type of selfless offering to help. I can't get over how tightly knit the Porsche community is and I have been lucky to have been helped by people far sharper than I am. I wanted the control for myself though because I like to tinker, i like to log, i like to road test, i like to log on track and I make changes constantly. I've lost count how many times I've flashed my car but it's nearing triple digits.
The next step is to be able to get more control over the cams so that i could in theory do all of this with GT4 software and provide X51 kits and have no issues with anything described above. For this reason I have kept folks at arm's length that have inquired about the X51 upgrade because I don't feel comfortable marketing things that I wouldn't at least be happy with if i were a customer and lights on the dash make everyone's life miserable. I'm rather happy with the power and torque now and the drivability is awesome. The dyno runs were done in 5th gear which was where my torque was hiding. This is a file with stock mapping that we threw in at the end of the day to see how aggressive stock GT4 and X51 GTS mapping are. If i can get the control over the cams i can fix that odd behavior at 4500 RPM and make some better power and torque. We did 40 dyno pulls and the map that I was using was strong and smooth but it had a bunch of ignition timing changes in it so we went back to stock for the 40th and final run and that's what generated that graph. This map is a bit less smooth but it shows the potential of this package without any tuning.
To give an update, below is a dyno run from last week from my ongoing Stage II project. I went back to try every single Cobb map available as far as cam timing, ignition, flappers, etc. The car is a Stage II which is the X51 upgrade, Cargraphic race headers, a flywheel that weighs half of what the stock one does and 5 gallons of 98 octane mixed on top of 10 gallons of some bad 92 octane that was causing awful knocking. The mapping is stock Porsche mapping for a 991 X51/GTS.
As of now I am continuing with the Cobb software because it gives me the control of the mapping and allows me to custom tune ECUs for customers. The control is awesome given that i can manipulate intake flaps, lambda tuning and it has allowed me to install race manifolds without cats and have no CELs. I can make sales in the paddock and put files in peoples' hands without relying on anyone else and this is huge for us. HOWEVER, in my quest to start with the proper base file, with my own tooling I programmed my car to that of a 991 GTS. While I have a more invasive software that allows me to turn off lights on the dash that are a result of my installing X51 software, you should see what the cluster used to look like. Anyone who attempts this will have a Christmas Tree for a dash with every single possible light on. THEREFORE I have not booked a customer for this yet because the result is no PSM, no ABS, no auto blipper and conlicts for TPMS and trans temps. Given that i have been at this very task since 2014, I knew this would happen if i tried 911 mapping in a Cayman. To this day, the only way to get this mapping in a 981 ECU AND have everything function as delivered from Porsche is to send the ECU to/from Germany. Of the 4 or 5 cars we sent out ECUs for, they are the only cars i know of worldwide that operate with lights on the cluster while running the factory 991 X51 GTS mapping. When i perfect the GTS mapping and get the next level of control i will be able to transfer everything over to the GT4 mapping and that means none of you will have to worry about any of this.
I am continuing on with the Cobb folks though because they have been great to work with, they're always responsive to my questions and have always offered to help, even at their expense. Before i go further, everyone to this date has also provided the same type of selfless offering to help. I can't get over how tightly knit the Porsche community is and I have been lucky to have been helped by people far sharper than I am. I wanted the control for myself though because I like to tinker, i like to log, i like to road test, i like to log on track and I make changes constantly. I've lost count how many times I've flashed my car but it's nearing triple digits.
The next step is to be able to get more control over the cams so that i could in theory do all of this with GT4 software and provide X51 kits and have no issues with anything described above. For this reason I have kept folks at arm's length that have inquired about the X51 upgrade because I don't feel comfortable marketing things that I wouldn't at least be happy with if i were a customer and lights on the dash make everyone's life miserable. I'm rather happy with the power and torque now and the drivability is awesome. The dyno runs were done in 5th gear which was where my torque was hiding. This is a file with stock mapping that we threw in at the end of the day to see how aggressive stock GT4 and X51 GTS mapping are. If i can get the control over the cams i can fix that odd behavior at 4500 RPM and make some better power and torque. We did 40 dyno pulls and the map that I was using was strong and smooth but it had a bunch of ignition timing changes in it so we went back to stock for the 40th and final run and that's what generated that graph. This map is a bit less smooth but it shows the potential of this package without any tuning.
Could you let us know what a stock GT4 does on that dyno?
Also could you explain why 5th revealed the torque? Should all GT4's be dynoed in 5th or is this just specific to the X51 setup?
I used to dyno in 4th because i don't like the drive speeds in 5th. At WOT in 5th gear at redline you're doing over 140mph i think. The rule of thumb has always been to find the 1:1 gear but these cars don't have a 1:1 gear. 4th gear is 1.13 and 5th is .95. To be totally honest, someone smarter than me needs to explain it because i figured 5th would produce lower results since it's a taller gear and the torque multiplying is therefore less.
A Dynojet is an awesome piece because it's simple, reliable and repeatable. They correct for heat, humidity, etc and can produce consistent numbers. Let me see if i can dig up a Dyonjet run of a GT4. The key is being consistent so if you dyno anything, you need to dyno it in the proper gear and then let the roller dyno tell the story.
Originally Posted by jmartpr
John...you really need that Cargraphics Exhausts system!
I know. I think my neighbors would kill me though if it got any louder. To reiterate, race manifolds are LOUD. When i dropped off my engine tuner, he told me he was in the elevator when he heard me pulling away.
Originally Posted by Fabspeed Motorsport
Great progress, keep on rockin John!
Thanks bud...I've barely had time to tinker with the thing given how busy we are and i was long overdue for an update.
To give an update, below is a dyno run from last week from my ongoing Stage II project. I went back to try every single Cobb map available as far as cam timing, ignition, flappers, etc. The car is a Stage II which is the X51 upgrade, Cargraphic race headers, a flywheel that weighs half of what the stock one does and 5 gallons of 98 octane mixed on top of 10 gallons of some bad 92 octane that was causing awful knocking. The mapping is stock Porsche mapping for a 991 X51/GTS.
As of now I am continuing with the Cobb software because it gives me the control of the mapping and allows me to custom tune ECUs for customers. The control is awesome given that i can manipulate intake flaps, lambda tuning and it has allowed me to install race manifolds without cats and have no CELs. I can make sales in the paddock and put files in peoples' hands without relying on anyone else and this is huge for us. HOWEVER, in my quest to start with the proper base file, with my own tooling I programmed my car to that of a 991 GTS. While I have a more invasive software that allows me to turn off lights on the dash that are a result of my installing X51 software, you should see what the cluster used to look like. Anyone who attempts this will have a Christmas Tree for a dash with every single possible light on. THEREFORE I have not booked a customer for this yet because the result is no PSM, no ABS, no auto blipper and conlicts for TPMS and trans temps. Given that i have been at this very task since 2014, I knew this would happen if i tried 911 mapping in a Cayman. To this day, the only way to get this mapping n a 981 ECU AND have everything function as delivered from Porsche is to send the ECU to/from Germany. Of the 4 or 5 cars we sent out ECUs for, they are the only cars i know of worldwide that operate with lights on the cluster while running the factory 991 X51 GTS mapping.[/SIZE][/B][/SIZE] When i perfect the GTS mapping and get the next level of control i will be able to transfer everything over to the GT4 mapping and that means none of you will have to worry about any of this.
I am continuing on with the Cobb folks though because they have been great to work with, they're always responsive to my questions and have always offered to help, even at their expense. Before i go further, everyone to this date has also provided the same type of selfless offering to help. I can't get over how tightly knit the Porsche community is and I have been lucky to have been helped by people far sharper than I am. I wanted the control for myself though because I like to tinker, i like to log, i like to road test, i like to log on track and I make changes constantly. I've lost count how many times I've flashed my car but it's nearing triple digits.
So John - to be clear - if a customer wanted the Stage II - X51 conversion - you could do it today, but it would require the German ECU tuning which is what you initially offered in your power kits, but folks got all up in arms about because it was $4,500 +/- when they could buy Cobb for a grand.
So it could be done, but the cost would need to be adjusted for the costly German ECU tune, correct?
Last I recall they German tuner offered you a 2nd ECU which could be swapped out, that would be included in their price, correct?
Thanks in advance and for the past info provided to all of us.
I ordered sport exhaust through you today! Let the mods begin
So John - to be clear - if a customer wanted the Stage II - X51 conversion - you could do it today, but it would require the German ECU tuning which is what you initially offered in your power kits, but folks got all up in arms about because it was $4,500 +/- when they could buy Cobb for a grand.
So it could be done, but the cost would need to be adjusted for the costly German ECU tune, correct?
Last I recall they German tuner offered you a 2nd ECU which could be swapped out, that would be included in their price, correct?
Thanks in advance and for the past info provided to all of us.
I ordered sport exhaust through you today! Let the mods begin
Thanks for the order!
To answer your question, yes sir. We could do it right now if we sent out the computer to Germany; the ECU would be returned with a cloned copy working with your 2 original keys, which is physically impossible to have without cloning.
I have been tinkering with this whole thing for 4 years now and when we build race cars that don't require the stock control units to function as delivered, i can do it because the 6 speed cars usually have motorsports ABS and dont need PSM/ABS anymore. For street cars though, you have a taller order...for customers with PDK, it's 100% impossible without sending the ECU out. We built a 3.8L X51 PDK car and I literally took the ECU out of the box from Germany and dropped it in and everything on the car works as delivered. My bag of tricks gets me in the door with the 6-speed but as mentioned, comes with issues. It still amazes me how they can do that with the PDK cars. Without them, I can't even get the PDK shifter out of P.
Cobb has promised that they will make getting me access to the cam control a priority and i believe them. Over the next 2 weeks I hope to have something and hope to be all done with Stage II once i go back to the dyno one more time with my new cam mapping that i made last time. My Mahle 3.99L pistons are done and it's my intention to marry the stroker kit to the existing X51 parts to try and create the world's most potent NA GT4 street car later this summer. It's been a lengthy process but the reward will be worth it.
Good news folks... i got some rather cool dyno information from my good customer JMARTPR who bought a set of Cargraphic Sport manifolds and added some Cargraphic "Cup" mufflers to deliver more sound than a standard Cargraphic street system with the intention of trying to maintain the stock tone of the GT4. I asked him to dyno the car with just the manifolds and mufflers and if we could get a comparison to a stock GT4; as a bonus, we also have a dyno run of a GT4 with solely the additional IPD plenum, 82mm TB and Cobb flash from a tuner down there.
It never ceases to amaze me how much the exhaust mods do for the car between 3K RPM and 5K RPM vs. the intake/tuning mods and i also find it interesting how essentially 3 different iterations have such similar power and torque curves over 5K RPM. It's clear that the combination of the 3 yields some rather awesome gains. I wouldn't be fixated on how low the nominal numbers are for either of the 3 curves as those dynos tend to read lower than your typical Dynojet dynos. What is important is that 3 things were compared using the same dyno. The computers correct for changing ambient conditions but the methodology is consistent.
IMO I think the smooth out of the curve (blue line) in the mid range is mostly the COBB Pro Tuning while the gains at the top end (blue line) is definitely the IPD/TB combo flowing more air....this shows how restricted on the intake the engine is at the upper rpms. I will do the COBB next week and will see the results.
It looks like new Headers, Tune, TB/IPD will give you some nice gains. I was going to hold off on the TB and Plenum but it looks like it gives some good gains
This powerband is so much more cleaner/linear than the stock heads GT4 which has that awful series of dips. I bet it feels much more relentless pulling through the powerband.
This powerband is so much more cleaner/linear than the stock heads GT4 which has that awful series of dips. I bet it feels much more relentless pulling through the powerband.
The power is super linear. The X51 manifold has a large contributing effect because the stock GT4 manifold and its small runners are good for making torque down low but the car starves for air once you cross the threshold.
05-23-2016, 09:19 AM
