[Alias1431]

https://carbahnautoworks.com/product...x3m40i-x4m40i/

The part I like best:
"Philosophy:
CarBahn software is designed to deliver the highest safe output possible. Smooth Power means software tuned correctly, not over-tuned. We always try to make a natural torque curve, not excessive torque at low RPM that falls off rapidly at high RPM. Excessive torque will break the tires loose, break the engine and drivetrain. Managed torque with a smooth delivery makes the car easier to drive thereby faster and more reliable. Most if not all our competitor’s tunes attempt to run too much boost, resulting in active knock corrections which causes surging during acceleration. CarBahn software also incorporates torque reduction in 1st and 2nd gears for manageable power delivery.

Durability:
Most if not all tunes on the market except CarBahn’s reduce safety parameters in the software in an attempt to extract more power. These safety parameters such as knock control sensitivity, super knocking control sensitivity, and catalyst thermal protection are tuned into your OEM software to prevent engine and catalyst failure. When we reduced all the supposed power robbing software protections we lost less than 8 HP and 8 LB/FT Torque. We have seen many damaged engines as result of reducing these safety parameters! It hardly seems worth it for 8HP."


I am looking for a SAFE, reliable tune that also improves low-speed drivability and turbo lag. (Stage 1 only) I don't have any reason thus far to doubt BM3, I know they're super popular, just hoping for additional data points. Thoughts on CarBahn?

[asyvan]

If they are true to their philosophy it sure seems the best way to tune. My F25 was tuned using BMW own M-performance chip, becasue i wanted safety and quality.

[suby01]

I would be interested in the information on the 2020 what they have. Seems this is currently information based on the older 2019 B58.

[DoubleZeroNineOneEight]

Don’t BM3 and MHD tune the transmission too? I wouldn’t hesitate if I had a carbahn dealer nearby. At this point, having now heard about ECU locking via updates, I may just hold out for a re-release of the Dinan box.

[Alias1431]

I don't think they tune the transmission, but I don't know enough to say more than that. I think there's a transmission tune by xhp?

[BMWApp]

Originally Posted by DoubleZeroNineOneEight

Don’t BM3 and MHD tune the transmission too? I wouldn’t hesitate if I had a carbahn dealer nearby. At this point, having now heard about ECU locking via updates, I may just hold out for a re-release of the Dinan box.

I wouldn't count on Dinan coming out with a piggyback for the X3 M40i if that's what you are looking for (I have one myself and am considering the Carbahn flash tune). They are focused on a flash tune for the B58 but don't have any ETA for when it will be released. From what I understand Dinan was starting to move away from piggybacks and towards flash tunes but that might change if ECUs start getting locked down with software updates as we are learning.

[AcidLotus]

Originally Posted by DoubleZeroNineOneEight

Don’t BM3 and MHD tune the transmission too? I wouldn’t hesitate if I had a carbahn dealer nearby. At this point, having now heard about ECU locking via updates, I may just hold out for a re-release of the Dinan box.

Not for any of the newer trannys mated to any B58s AFAIK.

[AcidLotus]

Never heard of CarBahn. Personally, I'd suggest BM3 due to the speed with which they bring feature updates out to all BMW models they support, not just newer models. BM3 also has a lot of experience doing this. CarBahn sounds like they're just making claims to differentiate themselves just enough for people to question going with more established players like BM3.

[Torinalth]

Dinan already scrapped the piggyback for our car. they had it in the works and dumped it a little over a year ago. no explanation why.

neither MHD or BM3 tune the transmission by themselves, both have tunes for transmissions but neither (and nobody for that matter) for our specific platform.

I'd personally would, and have, go with BM3. MHD makes more power from what ive seen, by a small margin but it's there. the real key to BM3 in my opinion is the massive support network in facebook for BM3, and the ultra quick intervention by the developers if you have issues. As far as blown engines, I have yet to hear of someone wrecking their motor on the standard OTS tunes.

2 big turbos have eaten engines, and one guy running a meth system that screwed up are the only major failures i've come across and both in the 340 platform. One 340 also torched his transmission. that's 3 total major losses from the time the B58 came out in the 3 series up through the b58 hitting every platform BMW uses..... lots of tunes by MHD, BM3, Dinan (supports b58 on other cars), as well as custom variants which include meth, port injection, larger turbos, etc, etc, etc. The fear is always great, but the failure rates are so so so low in the grand scheme of things. Go with a company that supports you and is KNOWN by others. even if not BM3, go mhd at least... but choose someone that's quality and keeps revising the tunes to give both more power and better usability. for me that was BM3

[Alias1431]

Originally Posted by Torinalth

choose someone that's quality and keeps revising the tunes to give both more power and better usability.

Do they really revise their tunes? That doesn't make sense to me. You would think they would achieve peak results for a given powertrain, then release that tune. To suggest otherwise hints at incompetence. To be clear, I am not suggesting BM3 isn't good at what they do, I'm sure they are, it's just that your phrasing gives me pause. Can you elaborate?

[BMWApp]

Originally Posted by AcidLotus

Never heard of CarBahn. Personally, I'd suggest BM3 due to the speed with which they bring feature updates out to all BMW models they support, not just newer models. BM3 also has a lot of experience doing this. CarBahn sounds like they're just making claims to differentiate themselves just enough for people to question going with more established players like BM3.

Carbahn is Steve Dinan. That's the company he started two years after he sold Dinan. So it's legit IMO. He always erred on the side of a little less power compared to his competitors but Carbahn claims 441 crank hp and 490 crank on-ft of torque for the X3 M40i. You can also buy the warranty option where they will match the remainder of your factory warranty in case the tune causes issues.

[Alias1431]

Originally Posted by BMWApp

Carbahn is Steve Dinan. That's the company he started two years after he sold Dinan. So it's legit IMO. He always erred on the side of a little less power compared to his competitors but Carbahn aims 441 crank hp and 490 crank on-ft of torque for the X3 M40i. You can also buy the warranty option where they will match the remainder of your factory warranty in case the tune causes issues.

Ahhh, didn't know that. What are the BMW "crank" numbers? Are they as advertised? Is what is advertised wheel? Something else?

[DoubleZeroNineOneEight]

Originally Posted by Torinalth

Dinan already scrapped the piggyback for our car. they had it in the works and dumped it a little over a year ago. no explanation why.

neither MHD or BM3 tune the transmission by themselves, both have tunes for transmissions but neither (and nobody for that matter) for our specific platform.

I'd personally would, and have, go with BM3. MHD makes more power from what ive seen, by a small margin but it's there. the real key to BM3 in my opinion is the massive support network in facebook for BM3, and the ultra quick intervention by the developers if you have issues. As far as blown engines, I have yet to hear of someone wrecking their motor on the standard OTS tunes.

2 big turbos have eaten engines, and one guy running a meth system that screwed up are the only major failures i've come across and both in the 340 platform. One 340 also torched his transmission. that's 3 total major losses from the time the B58 came out in the 3 series up through the b58 hitting every platform BMW uses..... lots of tunes by MHD, BM3, Dinan (supports b58 on other cars), as well as custom variants which include meth, port injection, larger turbos, etc, etc, etc. The fear is always great, but the failure rates are so so so low in the grand scheme of things. Go with a company that supports you and is KNOWN by others. even if not BM3, go mhd at least... but choose someone that's quality and keeps revising the tunes to give both more power and better usability. for me that was BM3

Carbahn was said to be Steve Dinan’s and regarding the Dinan Box for the X3M40i see the response from December.

[BMWApp]

Originally Posted by Alias1431

Ahhh, didn't know that. What are the BMW "crank" numbers? Are they as advertised? Is what is advertised wheel? Something else?

The crank numbers are power in the engine. What really matters is the power at the wheels. There is always some loss of power through the drivetrain going from the engine to the wheel. Chris at Carbahn said they estimate drivetrain loss as follows:

Manual/DCT - 12%
Rear wheel drive - 15%
xDrive - 17%

For the flash tune for the X3 M40i, Carbahn's dyno measured 366 hp and 407 lb-ft torque at the wheels which translates to the 441 hp and 490 lb-ft torque crank numbers they state.

[BMWApp]

Originally Posted by DoubleZeroNineOneEight

Carbahn was said to be Steve Dinan’s and regarding the Dinan Box for the X3M40i see the response from December.

So does this mean that Dinan is working on a piggyback tuner for the X3 M40i in addition to the B58 flash tune? That would give them two tuning options for the X3 M40i. I have the Dinan Elite V1 tuner on my 340i and given what I'm hearing about BMW starting to lock the DMEs with software updates, having a piggyback tuner is looking a little more appealing than flash tunes that may get overwritten with no ability to reflash back to the previous tune.

[DoubleZeroNineOneEight]

Originally Posted by BMWApp

So does this mean that Dinan is working on a piggyback tuner for the X3 M40i in addition to the B58 flash tune? That would give them two tuning options for the X3 M40i. I have the Dinan Elite V1 tuner on my 340i and given what I'm hearing about BMW starting to lock the DMEs with software updates, having a piggyback tuner is looking a little more appealing than flash tunes that may get overwritten with no ability to reflash back to the previous tune.

It appears Steve Dinan started up CarBahn and is no longer with Dinan (DinanCars). CarBahn offers a B58flash tune. That’s why earlier in the thread I said I wouldn’t hesitate to try a CarBahn tune, but a box was more appealing after learning that return to factory tune and ECU locking could occur during any dealer visit. In their December response to my email regarding a box for the x3m40i, DinanCars claims to be working on it. My BMW dealer and service center is also a Dinan (not CarBahn) reseller. So there is also that.

[BMWApp]

Originally Posted by DoubleZeroNineOneEight

It appears Steve Dinan started up CarBahn and is no longer with Dinan (DinanCars). CarBahn offers a B58flash tune. That's why earlier in the thread I said I wouldn't hesitate to try a CarBahn tune, but a box was more appealing after learning that return to factory tune and ECU locking could occur during any dealer visit. In their December response to my email regarding a box for the x3m40i, DinanCars claims to be working on it. My BMW dealer and service center is also a Dinan (not CarBahn) reseller. So there is also that.

Thanks for clarifying. As of now, I think the only piggyback tuners for the X3 M40i are RaceChip and JB4. I would love for Dinan to come out with one. They did release one for a short period of time but took it off the market because customers were having issues with it not providing any additional power. At least that's my understanding but I could be wrong.

[Alias1431]

Originally Posted by BMWApp

The crank numbers are power in the engine. What really matters is the power at the wheels. There is always some loss of power through the drivetrain going from the engine to the wheel. Chris at Carbahn said they estimate drivetrain loss as follows:

Manual/DCT - 12%
Rear wheel drive - 15%
xDrive - 17%

For the flash tune for the X3 M40i, Carbahn's dyno measured 366 hp and 407 lb-ft torque at the wheels which translates to the 441 hp and 490 lb-ft torque crank numbers they state.

Thanks!

[Torinalth]

Originally Posted by Alias1431

Do they really revise their tunes? That doesn't make sense to me. You would think they would achieve peak results for a given powertrain, then release that tune. To suggest otherwise hints at incompetence. To be clear, I am not suggesting BM3 isn't good at what they do, I'm sure they are, it's just that your phrasing gives me pause. Can you elaborate?

You are not serious are you? every single tune shop i've ever encountered has released revisions. This is across Audi, BMW, MB, Subaru, and Ford. It's irresponsible not to make revisions. With any new ECU they will always find new tricks on how to properly use the tables they are able to unlock. whether it's discovering a previously unknown table is a new fueling addition, knock correction, secondary sensor driven timing adjustment, or simply finding a new formulation on how to adjust the boost vs wgdc tables. If you only release a single tune and never update then how do you make use of new data? a greater sample size of fuels, slight engine variations, feedback from customers, running multiple cars from multiple years which might all have minor DME changes allows you to create safer AND better performing tunes. A one and done is more terrifying to me.

[Alias1431]

Originally Posted by Torinalth

You are not serious are you? every single tune shop i've ever encountered has released revisions. This is across Audi, BMW, MB, Subaru, and Ford. It's irresponsible not to make revisions. With any new ECU they will always find new tricks on how to properly use the tables they are able to unlock. whether it's discovering a previously unknown table is a new fueling addition, knock correction, secondary sensor driven timing adjustment, or simply finding a new formulation on how to adjust the boost vs wgdc tables. If you only release a single tune and never update then how do you make use of new data? a greater sample size of fuels, slight engine variations, feedback from customers, running multiple cars from multiple years which might all have minor DME changes allows you to create safer AND better performing tunes. A one and done is more terrifying to me.

Of course I was serious; I don't know about this stuff, hence my question and request for more information.

What are tables?

[Torinalth]

Originally Posted by Alias1431

Of course I was serious; I don't know about this stuff, hence my question and request for more information.

What are tables?

Sorry if I came across as a bit blunt, I took your question as more of being flippant than an actual request for information.

every single tuning platform operates essentially as a massive stack of spreadsheets. each individual one is called a table (at least on the platforms I've used). like any table (spreadsheet) it has an X and Y axis that works like a giant game of operational battleship. for target boost as an example, the Y axis would be throttle angle, while the X would be RPM, and the combo would tell the car what the desired boost to target. low throttle angle and low RPM, probably have a value for very low boost, 90%+ throttle angle and 5000 rpm? possibly something like 18psi. How do you get this to happen, enter WGDC table (wastegate duty cycle) or how hard the electrical solonoid works to keep the wastegate closed. This is repeated with things like global timing, AFR, additional timing, and when you stack all the tables on top of one another you get how your car performs. tweak things as needed to change how it currently behaves into how you want it to behave. the below link is to a sample timing table from my old subaru tuning platform i used, RomRaider

https://lh3.googleusercontent.com/pr...YENBe81HcCodrm

[AcidLotus]

Originally Posted by BMWApp

The crank numbers are power in the engine. What really matters is the power at the wheels. There is always some loss of power through the drivetrain going from the engine to the wheel. Chris at Carbahn said they estimate drivetrain loss as follows:

Manual/DCT - 12%
Rear wheel drive - 15%
xDrive - 17%

For the flash tune for the X3 M40i, Carbahn's dyno measured 366 hp and 407 lb-ft torque at the wheels which translates to the 441 hp and 490 lb-ft torque crank numbers they state.

That sounds horrible! Those sound like stock numbers out of the factory from BMW since the B58s and nearly every other BMW engine are underrated. I'm sure we can find a stock B58D putting 366 AWHP down in a dyno. Dinan stuff in the past has always been LOW on HP, so I'm not surprised these are low too.

And I'd think you're more apt to have problems with warranty with a piggyback than a flash. Piggy's just obfuscate numbers to make the computer think it's experiencing a condition it really isn't, whereas flash tunes have more more control and parameterizarion, and are thus inherently safer. Additionally, they can tell whether you put a piggy on the car just as easily as a flash tune if there is a warranty claim, so you're really not safe either way, and should just go with a flash. I've seen people flash their leases and return them when the lease is up, and the dealer sells the car as a CPO, so as long as you're looking for more power, might as well go the safer route and just flash it. If you're afraid you're gonna blow your engine and your warranty, save your money and remain stock. I personally know that if I blow the motor, I'll just buy a new one.