[flybigjet]

Ok guys-- I'm in Ely, NV for the night and will be in the Bay Area tomorrow night.

The car gets dropped off at Carbahn on Thursday. I have to decide about the "start up roar/cracks/pops/burbles".

Does anyone who's installed the tune have any insight? Chris sort of implied that I should stay with the stock burbles unless I really didn't like my neighbors.

I may possibly eventually get the Dinan axle-back, but that's as far as I'd be interested.

TIA--

[Thescout13]

Originally Posted by flybigjet

Ok guys-- I'm in Ely, NV for the night and will be in the Bay Area tomorrow night.

The car gets dropped off at Carbahn on Thursday. I have to decide about the "start up roar/cracks/pops/burbles".

Does anyone who's installed the tune have any insight? Chris sort of implied that I should stay with the stock burbles unless I really didn't like my neighbors.

I may possibly eventually get the Dinan axle-back, but that's as far as I'd be interested.

TIA--

The one I have driven kept the stock burbles and it's identical to stock, literally. Don't go more aggressive unless you really want that sound/image. If you are going to upgrade to Dinan eventually, definitely don't go more aggressive than stock, because then it will just be a bit too much (unless you are going for the too much vibe).

[flybigjet]

Originally Posted by Thescout13

The one I have driven kept the stock burbles and it's identical to stock, literally. Don't go more aggressive unless you really want that sound/image. If you are going to upgrade to Dinan eventually, definitely don't go more aggressive than stock, because then it will just be a bit too much (unless you are going for the too much vibe).

Thanks-- that's pretty much exactly what I'd worked out, but it's nice to get confirmation.

Stock burbles it is.

[pz619]

So I have the burble tune and it sounds exactly like stock. As for start up roar, I went under the car with a GoPro to see how it works. It appears to open the valves at startup for about a second then closes them again. The RPMs might be a little higher at engine start but that’s all that I can detect.

[Kleinacus]

Originally Posted by pz619

So I have the burble tune and it sounds exactly like stock. As for start up roar, I went under the car with a GoPro to see how it works. It appears to open the valves at startup for about a second then closes them again. The RPMs might be a little higher at engine start but that's all that I can detect.

This is enlightening. I expected not selecting the startup roar/overrun burbles to act as a delete not a retain stock. I thought they made a mistake with the map they flashed but maybe I need to ask for a cold start/burble delete custom map.

[KevM2]

Does anyone know if a Carbahn tune can only be installed at their shop?

[Kleinacus]

Originally Posted by KevM2

Does anyone know if a Carbahn tune can only be installed at their shop?

Dealer network is searchable on their website. Mine was installed during an oil change at my BMW dealership.

[pz619]

Originally Posted by Kleinacus

This is enlightening. I expected not selecting the startup roar/overrun burbles to act as a delete not a retain stock. I thought they made a mistake with the map they flashed but maybe I need to ask for a cold start/burble delete custom map.

Yeah I would think so? But I think someone else here said they didn't purchase the burble tune and it sounds like stock. I did make the purchase but it also sounds exactly like stock. Maybe there are subtle changes but it's not super noticeable to me.

[bioman]

Originally Posted by flybigjet

Changing out the heat exchanger simply because I'm figured it wan't all that much, and it will decrease the charge by 10-15 degrees.

BMW crippled the M2C on cooling-- I'm just helping it out a bit.

It wasn't outrageous, and I was sort of in the neighborhood since I wanted to do the CBC (as preventative) and the M3/4 intakes (again, fixing BMW's crippling of the car).

Are you getting the warranty with the CBC as well?
Whats are the CBC costs?

[flybigjet]

Originally Posted by bioman

Are you getting the warranty with the CBC as well?
Whats are the CBC costs?

According to Chris, nothing I'm doing will invalidate their warranty. I was very upfront about that-- it sure seemed to be a non-issue.

CBC is about $75 for parts and about 2-3 hours of labor iirc.

Since I'll have the bumper and heat exchanger pulled, some of the labor time will overlap.

[FreeDarko]

Instead of using CBC, doesn't CarBahn offer a different solution? Is that more expensive?

[flybigjet]

Originally Posted by FreeDarko

Instead of using CBC, doesn't CarBahn offer a different solution? Is that more expensive?

Sure. They do the crank hub fix.

Labors only 18 hours!

If I was going high hp, yes. But no for a mild tune.

The CBC is the 98% solution.

[bioman]

Originally Posted by flybigjet

According to Chris, nothing I'm doing will invalidate their warranty. I was very upfront about that-- it sure seemed to be a non-issue.

CBC is about $75 for parts and about 2-3 hours of labor iirc.

Since I'll have the bumper and heat exchanger pulled, some of the labor time will overlap.

Looks like you'll have an extra safety net with the warranty then.
I asked them about the CBC, but they weren't too keen on it for a solution. Pretty confident that their stage 1 was more than safe.

I'm still in the early stages of getting a feel for the stage 1, but it is a noticeable improvement over stock.

[akkando]

Originally Posted by KevM2

Ya based on all the posts here about charge cooler issues I think it's a great idea. I'm also going to upgrade it soon. There's three ive been thinking about and they're CSF, Mishimoto, or Evolution of Speed. Right now leaning towards EOS one...

What's wrong with the cooling on the m2c?

[KevM2]

Originally Posted by akkando

What's wrong with the cooling on the m2c?

Nothing! It's the ultimate cooling machine but the intercooler is not robust enough with higher stage tunes and prone to leaks

[flybigjet]

Ok-- I've been busy on a road trip, visiting family and friends and doing the Detail Jobs From Hell on three cars (ugh!), but I finally have some time to put down some thoughts on Carbahn:

The Carbahn shop is more or less in an industrial park in San Jose, and when you walk in-- WOW-- SPOTLESSLY clean. Three (count 'em-- THREE) Audi R8 race cars, a bunch of other pricy toys, another M2 on the rack (with about $50k into it so far), and their own machine/CNC area where they were turning out hub cranks from OEM BMW parts. Lots of lifts, very happy techs, and a lot of money on the hoof. Steve Dinan must be doing ok since he had a brand-new M8 sitting outside (with the outer edges of the tires already scalloped and worn!)

Chris was great-- gave me a very nice tour, introduced me to Steve Dinan, and gave me a loaner car at no cost for the time my car was in the shop. Since I was staying about 75 miles away with plans for the weekend, that was much appreciated. I planned on dropping off the car on a Thursday and picking it up on Monday, but they got things done quicker than I thought, so I was able to go back and pick it up on Friday afternoon. This allowed me to drive the car around Napa that weekend, which was a lot of fun.

I had a Mishimoto heat exchanger, VTT CBC, charcoal filters removed, Mishimoto oil catch can and OEM M4 intakes installed. The Mishimoto fit well AND has a stone guard, so that's good. The VTT CBC was installed STRICTLY for peace of mind (Yes, I know it's not the "real" solution, but it's also not 18 hours of labor). Chris didn't seem to have much of an opinion either way on the part. If I was going to go "nuts" on a build, I'd go for the full SCH fix, but not for a mild tune. As for the M4 intakes? In Chris' words-- "You might be on to something there". When they installed them, they did find that the intake "slot" on the vertical arm that the M4 parts clip to was a little worrysome-- they thought that it might negate the point of the M4 intakes, so they patched them up so the new intakes were the only point drawing air. In retrospect, I should have ordered the M4 vertical arms. Live and learn-- but now air's drawing from the kidney grills on either side of the heat exchanger.

Carbahn doesn't backdate the DME, so if you're locked, you're out of luck with the tablet and any future updates (Grr). Chris says they're soliciting resume's for someone to crack the DME, so if you're a tech-jockey, throw your hat into the ring so we can get that sorted! Anyhow, they don't actually remove the DME-- they remove the "air" attachments on the intercooler, sort of "flop" it out of the way, and attach their tuning machine directly to the DME-- at least that's how it was explained to me.

As to the software, I chose it BECAUSE it was a "mild" tune WITH warranty (and no, nothing I had installed is an issue with the warranty). I figure a blown motor is a LOT of money, and $750 wouldn't remotely cover Carbahn's costs-- I read that as they were VERY confident in their tune. I also liked that all reports to date were that it was very "BMW-like" and drove a lot like stock, but with additional power.

I agree with that assessment..... mostly.

The good? You have TONS of torque on demand-- the turbos "feel" like they spool a bit quicker/lag a bit less, and the "literally press you back into the seat" portion of the rpm gauge (i.e. Fun Band) seems to be very strong from about 3000-6000 rpm. It's a full-on hoot, and it's a great party trick to put the hp/tq gauges up on the center screen and watch the hp needle rapidly rise and the tq needle pretty much instantly get buried north of 480. Not particularly accurate, but fun to watch, nonetheless. And just flooring it in sixth on a highway off-ramp and being pushed back into your seat? Kind of cool.

The bad? The throttle is *very* twitchy in a MT from 1-2 and a bit less so on 2-3 shifts-- enough that I called Chris to confirm that there was nothing wrong with the tune. His response was that basically, that's the way it is and that he'd noticed that the clutch was more or less an "on/off switch" after the tune. Of course, he also noted that you could spin the wheels all the way through third gear with little to no effort, so there is that. Efficient is fine as long as you're smooth on the clutch (but the little "pop" that was there before is now a bit exacerbated). Sport feels like Sport+, and it's a challenge to be smooth with it, especially during "spirited" driving. I just gave up on Sport+-- almost 40 years of driving exclusively MT, and I felt like it was the first day I'd ever tried to row the gears. Supposedly the fix is to install the UCP (which is sitting in my garage waiting for me to get home) and/or the CDV delete. I'll be doing the UCP as soon as I get back and will consider the CDV delete when I get the SSK installed.

What else? The rev's climb a LOT faster than you're used to-- which can make starting on a hill sort of a challenge, but once you get used to the feel, that becomes a non-event. It's possible that installing the M4 intakes and/or removing the charcoal filters made a difference on throttle response as well, but since everything was done at once, there's no way to quantifiably determine that. Chris did mention that pulling the charcoal filters is pretty much the first thing they do to any car they get. He mentioned getting 10-15 hp on the dyno by removing them in other (non-M2) cars, but that certainly seems like a lot to me. I can't hear any more intake noise but a) I'm hard of hearing having been around jets for over 35 years and b) I installed the 2-series sound blanket on the underside of my hood.

Also-- I did not get the extra "start up roar & burbles"-- I vacillated about it for a while, but after talking to Chris, he talked me out of it. The car's plenty loud to my old ears and I didn't want to scare the neighbors, and the burbles sort of get old as it is. I wish I could have heard it before I had to make a decision, but I'm fine with how things sound-- it's basically stock on startup and burbling-- I'll eventually (probably) get the Dinan exhaust, so that will liven up the exhaust not a bit as well.

Overall? The tune is a hoot, and it just *begs* you to be a hooligan. I haven't done much in MDM as a) I didn't want to get an unpleasant surprise in all of the twisties since I'm still learning the new power profile and b) I didn't want to scare my sister or father silly with the car, but with DSC on, you'll get the light flickering in first, second and third gear at full throttle. It's also very obvious that the car is now significantly undertired-- I'll take steps on that as soon as I burn the stock rubber off the rims. I'll go up +1 with Michelin Pilot Sport 4S tires (255/35 & 275/35) when I do replace them-- I'd like to go +2 actually, but don't want to worry about rubbing on the front fender liners (thanks, BMW!)

My final impression? the tune is fun as hell-- it's basically the stock power curve-- intensified, and it would be pretty much perfect if the throttle wasn't so twitchy due to the quicker rpm spinup. I'm hoping the UCP and/or the CDV will solve that (relatively) minor issue and I'll be a happy man, indeed. I'm pleased to recommend the tune, with the caveat that a UCP and/or CDV delete will be in my future.

I'm attaching a copy of the dyno chart listed on Carbahn's site-- this is NOT my car, so I have no knowledge or ownership of it, so consider it for reference purposes only.

R.

[Montaver]

Originally Posted by flybigjet

Ok-- I've been busy on a road trip, visiting family and friends and doing the Detail Jobs From Hell on three cars (ugh!), but I finally have some time to put down some thoughts on Carbahn:

The Carbahn shop is more or less in an industrial park in San Jose, and when you walk in-- WOW-- SPOTLESSLY clean. Three (count 'em-- THREE) Audi R8 race cars, a bunch of other pricy toys, another M2 on the rack (with about $50k into it so far), and their own machine/CNC area where they were turning out hub cranks from OEM BMW parts. Lots of lifts, very happy techs, and a lot of money on the hoof. Steve Dinan must be doing ok since he had a brand-new M8 sitting outside (with the outer edges of the tires already scalloped and worn!)

Chris was great-- gave me a very nice tour, introduced me to Steve Dinan, and gave me a loaner car at no cost for the time my car was in the shop. Since I was staying about 75 miles away with plans for the weekend, that was much appreciated. I planned on dropping off the car on a Thursday and picking it up on Monday, but they got things done quicker than I thought, so I was able to go back and pick it up on Friday afternoon. This allowed me to drive the car around Napa that weekend, which was a lot of fun.

I had a Mishimoto heat exchanger, VTT CBC, charcoal filters removed, Mishimoto oil catch can and OEM M4 intakes installed. The Mishimoto fit well AND has a stone guard, so that's good. The VTT CBC was installed STRICTLY for peace of mind (Yes, I know it's not the "real" solution, but it's also not 18 hours of labor). Chris didn't seem to have much of an opinion either way on the part. If I was going to go "nuts" on a build, I'd go for the full SCH fix, but not for a mild tune. As for the M4 intakes? In Chris' words-- "You might be on to something there". When they installed them, they did find that the intake "slot" on the vertical arm that the M4 parts clip to was a little worrysome-- they thought that it might negate the point of the M4 intakes, so they patched them up so the new intakes were the only point drawing air. In retrospect, I should have ordered the M4 vertical arms. Live and learn-- but now air's drawing from the kidney grills on either side of the heat exchanger.

Carbahn doesn't backdate the DME, so if you're locked, you're out of luck with the tablet and any future updates (Grr). Chris says they're soliciting resume's for someone to crack the DME, so if you're a tech-jockey, throw your hat into the ring so we can get that sorted! Anyhow, they don't actually remove the DME-- they remove the "air" attachments on the intercooler, sort of "flop" it out of the way, and attach their tuning machine directly to the DME-- at least that's how it was explained to me.

As to the software, I chose it BECAUSE it was a "mild" tune WITH warranty (and no, nothing I had installed is an issue with the warranty). I figure a blown motor is a LOT of money, and $750 wouldn't remotely cover Carbahn's costs-- I read that as they were VERY confident in their tune. I also liked that all reports to date were that it was very "BMW-like" and drove a lot like stock, but with additional power.

I agree with that assessment..... mostly.

The good? You have TONS of torque on demand-- the turbos "feel" like they spool a bit quicker/lag a bit less, and the "literally press you back into the seat" portion of the rpm gauge (i.e. Fun Band) seems to be very strong from about 3000-6000 rpm. It's a full-on hoot, and it's a great party trick to put the hp/tq gauges up on the center screen and watch the hp needle rapidly rise and the tq needle pretty much instantly get buried north of 480. Not particularly accurate, but fun to watch, nonetheless. And just flooring it in sixth on a highway off-ramp and being pushed back into your seat? Kind of cool.

The bad? The throttle is *very* twitchy in a MT from 1-2 and a bit less so on 2-3 shifts-- enough that I called Chris to confirm that there was nothing wrong with the tune. His response was that basically, that's the way it is and that he'd noticed that the clutch was more or less an "on/off switch" after the tune. Of course, he also noted that you could spin the wheels all the way through third gear with little to no effort, so there is that. Efficient is fine as long as you're smooth on the clutch (but the little "pop" that was there before is now a bit exacerbated). Sport feels like Sport+, and it's a challenge to be smooth with it, especially during "spirited" driving. I just gave up on Sport+-- almost 40 years of driving exclusively MT, and I felt like it was the first day I'd ever tried to row the gears. Supposedly the fix is to install the UCP (which is sitting in my garage waiting for me to get home) and/or the CDV delete. I'll be doing the UCP as soon as I get back and will consider the CDV delete when I get the SSK installed.

What else? The rev's climb a LOT faster than you're used to-- which can make starting on a hill sort of a challenge, but once you get used to the feel, that becomes a non-event. It's possible that installing the M4 intakes and/or removing the charcoal filters made a difference on throttle response as well, but since everything was done at once, there's no way to quantifiably determine that. Chris did mention that pulling the charcoal filters is pretty much the first thing they do to any car they get. He mentioned getting 10-15 hp on the dyno by removing them in other (non-M2) cars, but that certainly seems like a lot to me. I can't hear any more intake noise but a) I'm hard of hearing having been around jets for over 35 years and b) I installed the 2-series sound blanket on the underside of my hood.

Also-- I did not get the extra "start up roar & burbles"-- I vacillated about it for a while, but after talking to Chris, he talked me out of it. The car's plenty loud to my old ears and I didn't want to scare the neighbors, and the burbles sort of get old as it is. I wish I could have heard it before I had to make a decision, but I'm fine with how things sound-- it's basically stock on startup and burbling-- I'll eventually (probably) get the Dinan exhaust, so that will liven up the exhaust not a bit as well.

Overall? The tune is a hoot, and it just *begs* you to be a hooligan. I haven't done much in MDM as a) I didn't want to get an unpleasant surprise in all of the twisties since I'm still learning the new power profile and b) I didn't want to scare my sister or father silly with the car, but with DSC on, you'll get the light flickering in first, second and third gear at full throttle. It's also very obvious that the car is now significantly undertired-- I'll take steps on that as soon as I burn the stock rubber off the rims. I'll go up +1 with Michelin Pilot Sport 4S tires (255/35 & 275/35) when I do replace them-- I'd like to go +2 actually, but don't want to worry about rubbing on the front fender liners (thanks, BMW!)

My final impression? the tune is fun as hell-- it's basically the stock power curve-- intensified, and it would be pretty much perfect if the throttle wasn't so twitchy due to the quicker rpm spinup. I'm hoping the UCP and/or the CDV will solve that (relatively) minor issue and I'll be a happy man, indeed. I'm pleased to recommend the tune, with the caveat that a UCP and/or CDV delete will be in my future.

I'm attaching a copy of the dyno chart listed on Carbahn's site-- this is NOT my car, so I have no knowledge or ownership of it, so consider it for reference purposes only.

R.

Thanks for the review!

Doesn't sound very good honestly, poor throttle mapping won't be cured with a UCP. The UCP just changes the length of the clutch throw lowering the bite point, it doesnt mechanically impact the drivetrain. At least with BM3 you can configure everything and experiment (i.e. burbles, rev matching, torque by gear etc.)

I'd like to see a tune with a much flatter torque curve across the rev range, i.e. tops out where the stock tune does but can hold that to 6-6.5kK RPM as per the Carbahn graph. The power looks nice. I think part of the problem with OTS tunes is its easier to 'feel' torque so they are all boosty and midrange. If I wanted that I'd drive a 340D. The stock tune is superior in this regard as the torque fall off is way less dramatic. BMW realise the naturally aspirated feeling is what people want, hence the M2CS has the same peak torque as the M2C. Has the additional benefit of protecting the rest of the mechanical's and reducing the chances of a spun hub.

[Thescout13]

Originally Posted by flybigjet

Ok-- I've been busy on a road trip, visiting family and friends and doing the Detail Jobs From Hell on three cars (ugh!), but I finally have some time to put down some thoughts on Carbahn:

The Carbahn shop is more or less in an industrial park in San Jose, and when you walk in-- WOW-- SPOTLESSLY clean. Three (count 'em-- THREE) Audi R8 race cars, a bunch of other pricy toys, another M2 on the rack (with about $50k into it so far), and their own machine/CNC area where they were turning out hub cranks from OEM BMW parts. Lots of lifts, very happy techs, and a lot of money on the hoof. Steve Dinan must be doing ok since he had a brand-new M8 sitting outside (with the outer edges of the tires already scalloped and worn!)

Chris was great-- gave me a very nice tour, introduced me to Steve Dinan, and gave me a loaner car at no cost for the time my car was in the shop. Since I was staying about 75 miles away with plans for the weekend, that was much appreciated. I planned on dropping off the car on a Thursday and picking it up on Monday, but they got things done quicker than I thought, so I was able to go back and pick it up on Friday afternoon. This allowed me to drive the car around Napa that weekend, which was a lot of fun.

I had a Mishimoto heat exchanger, VTT CBC, charcoal filters removed, Mishimoto oil catch can and OEM M4 intakes installed. The Mishimoto fit well AND has a stone guard, so that's good. The VTT CBC was installed STRICTLY for peace of mind (Yes, I know it's not the "real" solution, but it's also not 18 hours of labor). Chris didn't seem to have much of an opinion either way on the part. If I was going to go "nuts" on a build, I'd go for the full SCH fix, but not for a mild tune. As for the M4 intakes? In Chris' words-- "You might be on to something there". When they installed them, they did find that the intake "slot" on the vertical arm that the M4 parts clip to was a little worrysome-- they thought that it might negate the point of the M4 intakes, so they patched them up so the new intakes were the only point drawing air. In retrospect, I should have ordered the M4 vertical arms. Live and learn-- but now air's drawing from the kidney grills on either side of the heat exchanger.

Carbahn doesn't backdate the DME, so if you're locked, you're out of luck with the tablet and any future updates (Grr). Chris says they're soliciting resume's for someone to crack the DME, so if you're a tech-jockey, throw your hat into the ring so we can get that sorted! Anyhow, they don't actually remove the DME-- they remove the "air" attachments on the intercooler, sort of "flop" it out of the way, and attach their tuning machine directly to the DME-- at least that's how it was explained to me.

As to the software, I chose it BECAUSE it was a "mild" tune WITH warranty (and no, nothing I had installed is an issue with the warranty). I figure a blown motor is a LOT of money, and $750 wouldn't remotely cover Carbahn's costs-- I read that as they were VERY confident in their tune. I also liked that all reports to date were that it was very "BMW-like" and drove a lot like stock, but with additional power.

I agree with that assessment..... mostly.

The good? You have TONS of torque on demand-- the turbos "feel" like they spool a bit quicker/lag a bit less, and the "literally press you back into the seat" portion of the rpm gauge (i.e. Fun Band) seems to be very strong from about 3000-6000 rpm. It's a full-on hoot, and it's a great party trick to put the hp/tq gauges up on the center screen and watch the hp needle rapidly rise and the tq needle pretty much instantly get buried north of 480. Not particularly accurate, but fun to watch, nonetheless. And just flooring it in sixth on a highway off-ramp and being pushed back into your seat? Kind of cool.

The bad? The throttle is *very* twitchy in a MT from 1-2 and a bit less so on 2-3 shifts-- enough that I called Chris to confirm that there was nothing wrong with the tune. His response was that basically, that's the way it is and that he'd noticed that the clutch was more or less an "on/off switch" after the tune. Of course, he also noted that you could spin the wheels all the way through third gear with little to no effort, so there is that. Efficient is fine as long as you're smooth on the clutch (but the little "pop" that was there before is now a bit exacerbated). Sport feels like Sport+, and it's a challenge to be smooth with it, especially during "spirited" driving. I just gave up on Sport+-- almost 40 years of driving exclusively MT, and I felt like it was the first day I'd ever tried to row the gears. Supposedly the fix is to install the UCP (which is sitting in my garage waiting for me to get home) and/or the CDV delete. I'll be doing the UCP as soon as I get back and will consider the CDV delete when I get the SSK installed.

What else? The rev's climb a LOT faster than you're used to-- which can make starting on a hill sort of a challenge, but once you get used to the feel, that becomes a non-event. It's possible that installing the M4 intakes and/or removing the charcoal filters made a difference on throttle response as well, but since everything was done at once, there's no way to quantifiably determine that. Chris did mention that pulling the charcoal filters is pretty much the first thing they do to any car they get. He mentioned getting 10-15 hp on the dyno by removing them in other (non-M2) cars, but that certainly seems like a lot to me. I can't hear any more intake noise but a) I'm hard of hearing having been around jets for over 35 years and b) I installed the 2-series sound blanket on the underside of my hood.

Also-- I did not get the extra "start up roar & burbles"-- I vacillated about it for a while, but after talking to Chris, he talked me out of it. The car's plenty loud to my old ears and I didn't want to scare the neighbors, and the burbles sort of get old as it is. I wish I could have heard it before I had to make a decision, but I'm fine with how things sound-- it's basically stock on startup and burbling-- I'll eventually (probably) get the Dinan exhaust, so that will liven up the exhaust not a bit as well.

Overall? The tune is a hoot, and it just *begs* you to be a hooligan. I haven't done much in MDM as a) I didn't want to get an unpleasant surprise in all of the twisties since I'm still learning the new power profile and b) I didn't want to scare my sister or father silly with the car, but with DSC on, you'll get the light flickering in first, second and third gear at full throttle. It's also very obvious that the car is now significantly undertired-- I'll take steps on that as soon as I burn the stock rubber off the rims. I'll go up +1 with Michelin Pilot Sport 4S tires (255/35 & 275/35) when I do replace them-- I'd like to go +2 actually, but don't want to worry about rubbing on the front fender liners (thanks, BMW!)

My final impression? the tune is fun as hell-- it's basically the stock power curve-- intensified, and it would be pretty much perfect if the throttle wasn't so twitchy due to the quicker rpm spinup. I'm hoping the UCP and/or the CDV will solve that (relatively) minor issue and I'll be a happy man, indeed. I'm pleased to recommend the tune, with the caveat that a UCP and/or CDV delete will be in my future.

I'm attaching a copy of the dyno chart listed on Carbahn's site-- this is NOT my car, so I have no knowledge or ownership of it, so consider it for reference purposes only.

R.

On the torque twitchiness thing, I will say that you should give the adaptations a bit more time. After over a thousand miles it is a lot smoother than the first two weeks or so. That is in addition to the UCP + CDV. It drives like a dream now.

Other than that, glad you enjoyed your experience.

[KevM2]

Originally Posted by flybigjet

Ok-- I've been busy on a road trip, visiting family and friends and doing the Detail Jobs From Hell on three cars (ugh!), but I finally have some time to put down some thoughts on Carbahn:

The Carbahn shop is more or less in an industrial park in San Jose, and when you walk in-- WOW-- SPOTLESSLY clean. Three (count 'em-- THREE) Audi R8 race cars, a bunch of other pricy toys, another M2 on the rack (with about $50k into it so far), and their own machine/CNC area where they were turning out hub cranks from OEM BMW parts. Lots of lifts, very happy techs, and a lot of money on the hoof. Steve Dinan must be doing ok since he had a brand-new M8 sitting outside (with the outer edges of the tires already scalloped and worn!)

Chris was great-- gave me a very nice tour, introduced me to Steve Dinan, and gave me a loaner car at no cost for the time my car was in the shop. Since I was staying about 75 miles away with plans for the weekend, that was much appreciated. I planned on dropping off the car on a Thursday and picking it up on Monday, but they got things done quicker than I thought, so I was able to go back and pick it up on Friday afternoon. This allowed me to drive the car around Napa that weekend, which was a lot of fun.

I had a Mishimoto heat exchanger, VTT CBC, charcoal filters removed, Mishimoto oil catch can and OEM M4 intakes installed. The Mishimoto fit well AND has a stone guard, so that's good. The VTT CBC was installed STRICTLY for peace of mind (Yes, I know it's not the "real" solution, but it's also not 18 hours of labor). Chris didn't seem to have much of an opinion either way on the part. If I was going to go "nuts" on a build, I'd go for the full SCH fix, but not for a mild tune. As for the M4 intakes? In Chris' words-- "You might be on to something there". When they installed them, they did find that the intake "slot" on the vertical arm that the M4 parts clip to was a little worrysome-- they thought that it might negate the point of the M4 intakes, so they patched them up so the new intakes were the only point drawing air. In retrospect, I should have ordered the M4 vertical arms. Live and learn-- but now air's drawing from the kidney grills on either side of the heat exchanger.

Carbahn doesn't backdate the DME, so if you're locked, you're out of luck with the tablet and any future updates (Grr). Chris says they're soliciting resume's for someone to crack the DME, so if you're a tech-jockey, throw your hat into the ring so we can get that sorted! Anyhow, they don't actually remove the DME-- they remove the "air" attachments on the intercooler, sort of "flop" it out of the way, and attach their tuning machine directly to the DME-- at least that's how it was explained to me.

As to the software, I chose it BECAUSE it was a "mild" tune WITH warranty (and no, nothing I had installed is an issue with the warranty). I figure a blown motor is a LOT of money, and $750 wouldn't remotely cover Carbahn's costs-- I read that as they were VERY confident in their tune. I also liked that all reports to date were that it was very "BMW-like" and drove a lot like stock, but with additional power.

I agree with that assessment..... mostly.

The good? You have TONS of torque on demand-- the turbos "feel" like they spool a bit quicker/lag a bit less, and the "literally press you back into the seat" portion of the rpm gauge (i.e. Fun Band) seems to be very strong from about 3000-6000 rpm. It's a full-on hoot, and it's a great party trick to put the hp/tq gauges up on the center screen and watch the hp needle rapidly rise and the tq needle pretty much instantly get buried north of 480. Not particularly accurate, but fun to watch, nonetheless. And just flooring it in sixth on a highway off-ramp and being pushed back into your seat? Kind of cool.

The bad? The throttle is *very* twitchy in a MT from 1-2 and a bit less so on 2-3 shifts-- enough that I called Chris to confirm that there was nothing wrong with the tune. His response was that basically, that's the way it is and that he'd noticed that the clutch was more or less an "on/off switch" after the tune. Of course, he also noted that you could spin the wheels all the way through third gear with little to no effort, so there is that. Efficient is fine as long as you're smooth on the clutch (but the little "pop" that was there before is now a bit exacerbated). Sport feels like Sport+, and it's a challenge to be smooth with it, especially during "spirited" driving. I just gave up on Sport+-- almost 40 years of driving exclusively MT, and I felt like it was the first day I'd ever tried to row the gears. Supposedly the fix is to install the UCP (which is sitting in my garage waiting for me to get home) and/or the CDV delete. I'll be doing the UCP as soon as I get back and will consider the CDV delete when I get the SSK installed.

What else? The rev's climb a LOT faster than you're used to-- which can make starting on a hill sort of a challenge, but once you get used to the feel, that becomes a non-event. It's possible that installing the M4 intakes and/or removing the charcoal filters made a difference on throttle response as well, but since everything was done at once, there's no way to quantifiably determine that. Chris did mention that pulling the charcoal filters is pretty much the first thing they do to any car they get. He mentioned getting 10-15 hp on the dyno by removing them in other (non-M2) cars, but that certainly seems like a lot to me. I can't hear any more intake noise but a) I'm hard of hearing having been around jets for over 35 years and b) I installed the 2-series sound blanket on the underside of my hood.

Also-- I did not get the extra "start up roar & burbles"-- I vacillated about it for a while, but after talking to Chris, he talked me out of it. The car's plenty loud to my old ears and I didn't want to scare the neighbors, and the burbles sort of get old as it is. I wish I could have heard it before I had to make a decision, but I'm fine with how things sound-- it's basically stock on startup and burbling-- I'll eventually (probably) get the Dinan exhaust, so that will liven up the exhaust not a bit as well.

Overall? The tune is a hoot, and it just *begs* you to be a hooligan. I haven't done much in MDM as a) I didn't want to get an unpleasant surprise in all of the twisties since I'm still learning the new power profile and b) I didn't want to scare my sister or father silly with the car, but with DSC on, you'll get the light flickering in first, second and third gear at full throttle. It's also very obvious that the car is now significantly undertired-- I'll take steps on that as soon as I burn the stock rubber off the rims. I'll go up +1 with Michelin Pilot Sport 4S tires (255/35 & 275/35) when I do replace them-- I'd like to go +2 actually, but don't want to worry about rubbing on the front fender liners (thanks, BMW!)

My final impression? the tune is fun as hell-- it's basically the stock power curve-- intensified, and it would be pretty much perfect if the throttle wasn't so twitchy due to the quicker rpm spinup. I'm hoping the UCP and/or the CDV will solve that (relatively) minor issue and I'll be a happy man, indeed. I'm pleased to recommend the tune, with the caveat that a UCP and/or CDV delete will be in my future.

I'm attaching a copy of the dyno chart listed on Carbahn's site-- this is NOT my car, so I have no knowledge or ownership of it, so consider it for reference purposes only.

R.

Did you also change the top mount intercooler or just the front heat exchanger? I wonder if a top mount intercooler upgrade would be just as effective and also removes the oem one which appears to be a potential leak problems

[flybigjet]

Originally Posted by KevM2

Did you also change the top mount intercooler or just the front heat exchanger? I wonder if a top mount intercooler upgrade would be just as effective and also removes the oem one which appears to be a potential leak problems

Just the front heat exchanger.

[ssabripo]

Originally Posted by flybigjet

Overall? The tune is a hoot, and it just *begs* you to be a hooligan. I haven't done much in MDM as a) I didn't want to get an unpleasant surprise in all of the twisties since I'm still learning the new power profile and b) I didn't want to scare my sister or father silly with the car, but with DSC on, you'll get the light flickering in first, second and third gear at full throttle. It's also very obvious that the car is now significantly undertired-- I'll take steps on that as soon as I burn the stock rubber off the rims. I'll go up +1 with Michelin Pilot Sport 4S tires (255/35 & 275/35) when I do replace them-- I'd like to go +2 actually, but don't want to worry about rubbing on the front fender liners (thanks, BMW!)

My final impression? the tune is fun as hell-- it's basically the stock power curve-- intensified, and it would be pretty much perfect if the throttle wasn't so twitchy due to the quicker rpm spinup. I'm hoping the UCP and/or the CDV will solve that (relatively) minor issue and I'll be a happy man, indeed. I'm pleased to recommend the tune, with the caveat that a UCP and/or CDV delete will be in my future.

I'm attaching a copy of the dyno chart listed on Carbahn's site-- this is NOT my car, so I have no knowledge or ownership of it, so consider it for reference purposes only.

R.

thanks for the review!!

I have my appointment for next monday to get this done, and looking forward to it. My car is DCT, so looking forward to see if there is hopefully less "twitch" on my car compared to all you guys with MT trannies. Also, I am running 295/30r + 265/30f tires, so hopefully that will help keep the beast in check somewhat.

Will keep you guys posted as well, but please do share additional comments and insights into your car as the days go by.

[Thescout13]

Originally Posted by ssabripo

thanks for the review!!

I have my appointment for next monday to get this done, and looking forward to it. My car is DCT, so looking forward to see if there is hopefully less "twitch" on my car compared to all you guys with MT trannies. Also, I am running 295/30r + 265/30f tires, so hopefully that will help keep the beast in check somewhat.

Will keep you guys posted as well, but please do share additional comments and insights into your car as the days go by.

Look forward to it. Keep us updated on the rubber. All I can say is to echo fly that the tune highlights how under tired the car is for that increase in power and torque. I'm sure the tires you threw on (assuming a good brand which I thing you did the PS4S IIRC) will hook nicely.