Which gears

stkjock

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Whoever is writing your tunes for you needs to make the change. The X4 will either let you change certain parameters provided you’re using the SCT preloaded tunes or it locks those features once you go to using custom tunes at which point your tuner has to write the change into the custom tune
not totally accurate, the tune writer can leave parameters unlocked to be adjusted by the end user, typically Rev/mile, gear ratio are left to be adjusted.
 

RocketcarX

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not totally accurate, the tune writer can leave parameters unlocked to be adjusted by the end user, typically Rev/mile, gear ratio are left to be adjusted.
I had Lito leave as much as possible unlocked in my tuner, Some of the features are there but have no effect. To be honest I haven't checked to see if the speedo related functions are still intact. There was a recent SCT update that rendered even fewer options to adjust available when you have custom tunes
 

46addict

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Just trying to learn here:

Why did the end user made changes, per post #36, change the speedometer error from 20+ to 5-8 MPH while other changes had no affect?

Thanks,

Joe
That is the same question that 06 T-Red is trying to figure out. There was someone else on FB who had this same problem so it isn't just one X4/car being affected by this.

On a sidenote SCT has been disappointing from a hardware and software standpoint. I've had two X3s fail. One stopped datalogging and the other refused to boot up when plugged in. I talked to their customer support about getting them repaired but they said my serials were too old to be serviceable. Livelink 6.5 was a PITA at times because it would not log with the engine running. So I had to be in a key on/engine off state to begin logging and then start the engine to collect data and sometimes it would take multiple attempts.

I eventually ponied up for an X4 and my tuner was kind enough to send me a new file to match the new device serial with no complaints. I will say the X4 paired with Livelink GenII is a big improvement over the old combo. Time will tell if it's still operational 5 years from now.
 

06 T-RED S/C GT

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Whoever is writing your tunes for you needs to make the change. The X4 will either let you change certain parameters provided you’re using the SCT preloaded tunes or it locks those features once you go to using custom tunes at which point your tuner has to write the change into the custom tune

Apparently, after SCT support followed up with me on yesterday, I was informed that despite the fact that Brenspeed left the Rev/Mile, Gear Ratio parameters unlocked to be adjusted by the end user, the reason the X4 would NOT flash the 3:55 gear ratio change into my vehicle's ECM was due from a direct result of the custom tune being written/adjusted for the 4:10 axle ratio. I was also informed that if I want to use adjustable options? SCT strongly suggests and recommends getting a new tune that DOES NOT have the axle ratio adjusted in the tune and just have the options left open. In other words, had Brenspeed not adjusted the axle ratio in the tune by just leaving the gear ratio parameters set at the OEM/stock settings? this would've allowed for the vehicle's ECM to accept the axle ratio adjustment changes from the X4 Programmer.

Just trying to learn here:

Why did the end user made changes, per post #36, change the speedometer error from 20+ to 5-8 MPH while other changes had no affect?

Thanks,

Joe

Joe, to answer your question? the explanation from the senior SCT support rep was this. The Gear ratio parameter is considered part of the OEM calibration, once that has been changed? the axle ratio must be flashed back to stock before the vehicle's ECM will allow the end user to make adjustment changes thru a hand-held tuning device, otherwise, the ECM will prevent the tuning device from making changes to the axle ratio. As for making changes to the Revs per mile are concerned, I was informed they're considered on a different table parameter over the axle ratio and can, therefore, be adjusted without having to return the gear ratio back to stock first. As for the speedometer error? the error change was a direct result of not knowing what the correct tire rev specs per hour are for 285/40/18" tires along with the issues I'm going thru with not being able to make adjustments to the axle ratio.

Anyway, hope this helps clarify any confusion I may have caused on my part when addressing your questions and concerns.

-Rocky

not totally accurate, the tune writer can leave parameters unlocked to be adjusted by the end user, typically Rev/mile, gear ratio are left to be adjusted.

Dave, you're absolutely 100% spot on, as this was exactly the explanation I was provided by the SCT senior tech support rep in which I spoke with on yesterday.


-Rocky

I had Lito leave as much as possible unlocked in my tuner, Some of the features are there but have no effect. To be honest I haven't checked to see if the speedo related functions are still intact. There was a recent SCT update that rendered even fewer options to adjust available when you have custom tunes

It really all depends on your custom tuning vendor. Usually, most will only unlock parameters such as tire revs for adjusting the speedo, along with unlocking the axle ratio, making adjustments for cold air intakes and for adjusting hi-low speed fan settings. However, I'm not able to make any adjustment changes to parameters such as Air/Fuel and Timing/Spark as my tuning vendor has all those parameters disabled in the custom tune along with all preloaded SCT tuning file parameters as well.

That is the same question that 06 T-Red is trying to figure out. There was someone else on FB who had this same problem so it isn't just one X4/car being affected by this.

On a sidenote SCT has been disappointing from a hardware and software standpoint. I've had two X3s fail. One stopped datalogging and the other refused to boot up when plugged in. I talked to their customer support about getting them repaired but they said my serials were too old to be serviceable. Livelink 6.5 was a PITA at times because it would not log with the engine running. So I had to be in a key on/engine off state to begin logging and then start the engine to collect data and sometimes it would take multiple attempts.

I eventually ponied up for an X4 and my tuner was kind enough to send me a new file to match the new device serial with no complaints. I will say the X4 paired with Livelink GenII is a big improvement over the old combo. Time will tell if it's still operational 5 years from now.

Well, it's sure nice to know that I'm not the only person who's been going thru the very same issues lol. And I agree wholeheartedly that SCT should fully provide support for their older tuning devices by continuing to provide updates/repairs for them. That being said, I couldn't agree more that from both a hardware and software standpoint, SCT has most definitely been very disappointing to say the very least IMHO!
 
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06 T-RED S/C GT

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Update: Brenspeed is writing a new revision tune file by changing the axle ratio parameters in the custom tune back to factory stock as requested by the SCT senior tech support rep I spoke with on yesterday. Brenspeed also assured me that they'll leave the parameters open in the custom tune unlocked in order to make any adjustments such as revs per mile and any other future axle ratio changes, if necessary. Once the axle ratio is put back to stock, the gear ratio parameters will no longer be locked out and the end user will then be able to make adjustments.
 
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06 T-RED S/C GT

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Went ahead and loaded the new revision tune with 3:55 in the custom tune file. Did several test runs at different revs per mile and in the end, went with 745 RPM. The speedo is now within 4-5 MPH of the actual speed readout of the GPS. At any rate, it appears that SCT was spot on about having to re-flash the axle ratio parameter back to OEM/stock before adjustment changes can be made by the end user. Needless to say, lesson learned lol.
 

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