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      05-26-2019, 04:35 PM   #177
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Originally Posted by Karazy View Post
What I meant by DCT was Dual clutch transmission. I think we may be talking about two different things. And I'm referring to the new M2 Competition.


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Originally Posted by landapanda View Post
Throttle, shifting and steering input are not configurable when in DCT, though I would love to see that option added. Of course, you can flash the car and program whatever set of configurations you'd like, but you have to consider that it will likely impact your warranty. Check our this article:

http://www.bimmerfile.com/2016/02/22...ng-the-bmw-m2/
Yeah - we are talking about two different things. I was referring to Dynamic Stability Control. Slight dyslexia snaeking in.
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      05-26-2019, 05:42 PM   #178
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Yeah - we are talking about two different things. I was referring to Dynamic Stability Control. Slight dyslexia snaeking in.
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      11-24-2019, 10:49 AM   #179
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I’ve been running BS in my 2018 LCI since 12/17, I think I turned 1,600mi on the way to the event. I run with the Buccaneer Region SCCA in north FL. It's been interesting reading about everyone’s experiences thus far with the M2. In my neck of the woods, there’s two other M2’s I regularly encounter, 1 local (SM car) and another (BS) in a neighboring region… which I’ll get to shortly. I consider myself a pretty decent driver and have about 15 total years of autocrossing under my belt. I built up a WRX for a national run at ESP back in the day and inevitably blew up the glass transmission at the Dixie NT due to the 285 A6s. From CRXs to wild A-MODs, I’ve run the gamut with autocross cars. I settled on the M2 because it seemed like the perfect balance between a car that I could drive to the events and still be competitive at the local national tours. Locally, I’m consistently top 5 in both raw and pax.

I knew any tires I ordered with the car when I bought it new were not re71rs, so I used the stock set to get to know the car and knock the dust off my driving. I blew through the stock set in about 8 months or so using our airstrip’s turn around as a giant drifting turn creating what locally was known as “the smoke show”. Lots of beautiful pictures of those events.

I’ve run the stock size re71r’s for about two years now and really like a low pressure setting (28psi square) and don’t have any noticeable understeer making it easy to drive with the right foot. One *major* malfunction I had with running low pressures were the TPMSs. Those f***ers flipped out on me probably 6 or more times mid-run even after resetting them at the start line. I finally just had to remove them entirely.

Having now done two years on stock wheels and tire sizes, I’m seriously looking into maxing out the B-Street allowance. There’s a local Camaro that is a killer driver and we used to trade wins but over the past four or so events, he’s really starting to pull ahead. The BS Camaros nationally are tough to keep up with using a totally stock setup but the M2, Camaro, and Tesla definitely seem to be the cars to have in the class.

The M2 in the neighboring region of CFR just so happens to be this year’s B-Street champion who actually drove a Tesla in Topeka but is normally in an M2. He was at Dixie this past year in the M2 and won with me 8th of 17 (results). His setup is monstrous, 285/30/18s with the Dinan bar in the front and 305/30/19 in the rear. He said he likes the gearing that 18s at the rear give but you just run out of speed too quickly.

I’m a little hesitant to add the front bar. The bars are pricey, no matter what brand, and I’d rather spend the extra money to get the right part the first time and I’m super annoyed that you can’t get just the front bar from Dinan. Given the 30mm delta from the stock size to the 40mm delta with the larger size, I feel like I’m still not going to have any understeer issues. That said, reducing front body roll will likely be necessary to prevent rubbing with a 285 tire in the front.

I decided I was not going to make it to nationals when I blew up the WRX, and just wanted to be fast locally and not have to tow anything. That was up until I had someone locally come to me about making a run for it in the M2 next year. This individual did beat me in my own car at one of our road course autocrosses (I have excuses, I swear), and has prompted me to start reconsidering it. While we know there’s no way we’re going to win, tickling the top 5 and getting a top 10 would be pretty ecstatic for either of us and attending nationals has always been something I wanted to do. I haven’t said yes because the car will slip out of warranty literally a month before and it’s a *really* long drive from NE Florida to Topeka.

Going to nationals would definitely require moving to the larger tire size, but the local quick camaro has been talking about moving to CAM-C which will likely take him out of the top pax positions and move me up the ranks without having to change tire sizes. I took the local BS championship last year. This year the quick Camaro pulled a Lewis Hamilton and clinched the championship for the year before the last two events could take place. The good news is I have decent rear tire life left and just replaced the fronts before the last event, so I have a few events before needing to make a commitment one way or another.

I’d like to hear how everyone’s season has/is shaking out for them and continued thoughts on the sway bars and tire pressures. Running in a stock class is not something I’m used to doing and having such limiting allowed modifications makes it challenging to maximize the vehicles potential performance. That said, I don’t miss trailering and the reliability issues of highly modified race cars. B Street is a super fun group of cars and people.
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      12-03-2019, 07:45 PM   #180
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Phil -- the M2 can definitely get it done in BS and there are rumblings of moving the Tesla although it has not been out for comment but is "subject to be monitored". David M. is very fast in both cars. Get the right front bar and pay the price. Dinan worked wonders for me on my now departed M3. Get 18 wheels. Consumables cost less, the tires clear easier which means you can fit wider. Yoko's are the trick. Nat's are held in Lincoln not Toledo. You're showing your age. Nice to see you post. I'm now in a CTR and will be in Lincoln next year in DS.
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      01-20-2020, 04:04 PM   #181
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Phil -- the M2 can definitely get it done in BS and there are rumblings of moving the Tesla although it has not been out for comment but is "subject to be monitored". David M. is very fast in both cars. Get the right front bar and pay the price. Dinan worked wonders for me on my now departed M3. Get 18 wheels. Consumables cost less, the tires clear easier which means you can fit wider. Yoko's are the trick. Nat's are held in Lincoln not Toledo. You're showing your age. Nice to see you post. I'm now in a CTR and will be in Lincoln next year in DS.
OHI We're debating a run to nats this year. Lots of things to weigh with that trip. Dixie will set the tone. Disappointed that Charlotte isn't on the calendar this year but I'm debating Bristol and Peru as an excuse to get back up there to see folks just like yourself!

Now that the Tesla was bumped out to SS, FS, and DS, the M2 still seems like the right car to have nationally.

I'm hearing more and more about the yoko's... are they really that much better than the RE71s? I've been very happy with the RE71s so far.

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      01-20-2020, 08:59 PM   #182
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OHI We're debating a run to nats this year. Lots of things to weigh with that trip. Dixie will set the tone. Disappointed that Charlotte isn't on the calendar this year but I'm debating Bristol and Peru as an excuse to get back up there to see folks just like yourself!

Now that the Tesla was bumped out to SS, FS, and DS, the M2 still seems like the right car to have nationally.

I'm hearing more and more about the yoko's... are they really that much better than the RE71s? I've been very happy with the RE71s so far.
I'd agree but I'm now in a Civic Type R which I also feel is the right car in DS for non-Pro events. PM me.
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      10-03-2020, 02:20 PM   #183
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Hello all,

I just bought a 2018 M2 to use as both a daily and autox car. I'll probably start taking it to the track once my new car paranoia wears off, too.

I've been running an E46 M3 in FS for the past 5 years. I really enjoyed the car but it's getting old and SCCA does not seem interested in classing it reasonably, so I figured it's time to move on. I decided to jump on an M2 that popped up locally, and I'm quite excited about it, but I'm finding the jump in technology level a little overwhelming (I've never owned a car newer than 2006 before now). I want to make sure I understand what I'm doing before I start buying stuff.

In my E46, I ran 18" wheels with no TPMS, Koni Yellow shocks, and a front sway bar. I ran RE71R's until recently when I switched to Supercar3's which worked much better. The E46 did not care if TPMS was removed other than it would give me a nuisance light every once in a while. The car had a binary sport mode that simply advanced the throttle mapping so most of the throttle control was in in the top half of the pedals movement, which was frankly just stupid so I left it in normal mode for better control.

After reading the owner's manual for the M2, things have clearly gotten a lot more advanced.

For TPMS, it seems some people are choosing to run TPMS on their autox/track wheels. Is this because the car might go into limp mode if TPMS is not functional? Or does having TPMS functional provide some other benefit that I'm not understanding?

For sport mode, I found a chart someone posted online that shows the different modes. It looks like the easiest thing to do is simply turn DSC fully off.

Once I get this sorted out in my head, my plan is to buy 18" wheels either with or without TPMS (whichever one makes more sense) and mount Supercar3's again. I'll may get a second set with Yok's if I decide to go to any National level events next year. I'll probably stick with just that for an event or two before I start messing with shocks or swaybars. The M2 seems to handle a bit better out of the box than the E46 from what I've felt so far, so it may not need much. If I do upgrade I'll probably skip Koni Yellows and go straight to a high-end shock.

Also, I haven't seen much talk about exhaust options. Does anyone know what the stock exhaust weighs?
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      10-03-2020, 03:39 PM   #184
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The car will go into "comfort" mode if the TPMS detect "low" tire pressures, which is anything below 30PSI, I believe. Obviously, if you're running tires at 32 or 33 hot, when they're cold you might get a low pressure warning that throws you out of sport/sport+. Pain in the ass if you're about to get onto the track, as me how I know... You have to stop the car and trigger a reset, which will let you switched back into a different mode while the TPMS remeasure, after which you can hopefully have them up to temp/pressure.

I think most folks tend to get them because it's cheaper and less of a pain in the ass to try and code out: https://f30.bimmerpost.com/forums/sh...8&postcount=24

I've been wondering if there's a way to drop the "low" value from 30 to 28 or 26PSI, because I'd like to know if the tires are leaking or flat, but not if I just like them low...

I usually leave the car in sport+ (with Euro MDM and M4GTS diff settings) because full DSC off can get you sideways fairly quickly especially when the rear is unloaded and you get back in the gas too quickly (at least in my experience).
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      10-03-2020, 06:12 PM   #185
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Originally Posted by asciimike View Post
The car will go into "comfort" mode if the TPMS detect "low" tire pressures, which is anything below 30PSI, I believe. Obviously, if you're running tires at 32 or 33 hot, when they're cold you might get a low pressure warning that throws you out of sport/sport+. Pain in the ass if you're about to get onto the track, as me how I know... You have to stop the car and trigger a reset, which will let you switched back into a different mode while the TPMS remeasure, after which you can hopefully have them up to temp/pressure.

I think most folks tend to get them because it's cheaper and less of a pain in the ass to try and code out: https://f30.bimmerpost.com/forums/sh...8&postcount=24

I've been wondering if there's a way to drop the "low" value from 30 to 28 or 26PSI, because I'd like to know if the tires are leaking or flat, but not if I just like them low...

I usually leave the car in sport+ (with Euro MDM and M4GTS diff settings) because full DSC off can get you sideways fairly quickly especially when the rear is unloaded and you get back in the gas too quickly (at least in my experience).
Yeah, I definitely do not want to code out TPMS because I want to know if my daily driver tires are leaking. Are there are any known negative effects if you simply put on non TPMS wheels? The Owner's Manual says it will throw a big error, but does it prevent you from turning DSC off?
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      10-03-2020, 07:30 PM   #186
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The car will go into "comfort" mode if the TPMS detect "low" tire pressures, which is anything below 30PSI, I believe. Obviously, if you're running tires at 32 or 33 hot, when they're cold you might get a low pressure warning that throws you out of sport/sport+. Pain in the ass if you're about to get onto the track, as me how I know... You have to stop the car and trigger a reset, which will let you switched back into a different mode while the TPMS remeasure, after which you can hopefully have them up to temp/pressure.

I think most folks tend to get them because it's cheaper and less of a pain in the ass to try and code out: https://f30.bimmerpost.com/forums/sh...8;postcount=24

I've been wondering if there's a way to drop the "low" value from 30 to 28 or 26PSI, because I'd like to know if the tires are leaking or flat, but not if I just like them low...

I usually leave the car in sport+ (with Euro MDM and M4GTS diff settings) because full DSC off can get you sideways fairly quickly especially when the rear is unloaded and you get back in the gas too quickly (at least in my experience).
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Originally Posted by JustAWhisper View Post


In my E46, I ran 18" wheels with no TPMS, Koni Yellow shocks, and a front sway bar. I ran RE71R's until recently when I switched to Supercar3's which worked much better. The E46 did not care if TPMS was removed other than it would give me a nuisance light every once in a while. The car had a binary sport mode that simply advanced the throttle mapping so most of the throttle control was in in the top half of the pedals movement, which was frankly just stupid so I left it in normal mode for better control.

What size supercar3s? Better overall or just better grip?

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Originally Posted by asciimike View Post

I usually leave the car in sport+ (with Euro MDM and M4GTS diff settings) because full DSC off can get you sideways fairly quickly especially when the rear is unloaded and you get back in the gas too quickly (at least in my experience).
How do you get euro mdm and m4gts diff settings?
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      10-04-2020, 06:19 AM   #187
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Originally Posted by JustAWhisper View Post
Yeah, I definitely do not want to code out TPMS because I want to know if my daily driver tires are leaking. Are there are any known negative effects if you simply put on non TPMS wheels? The Owner's Manual says it will throw a big error, but does it prevent you from turning DSC off?
The TPMS will go off if it detects a drop in pressure passed a predefined threshold in one or more tires. For example, I run 32-35psi on the street but for autox I run 28psi. Without fail the TPMS would go off on first run because 28psi (albeit a safe street pressure) was too far off where it was used to monitoring. If you ran your autox pressure on the street, this wouldn't be an issue.

Everytime I crank up the car I get the warning message on the display. I just hit OK and everything runs as normal except of the 1 alert message (I get 2 b/c of my tire rack windshield banner blocking part of the front facing camera lol). At events, I pull up to my grid spot, put the car in sport+ and turn DSC off. I don't touch the electronics nor turn the car off until the heat is over (sometimes 2+hrs). When finished, I just air back up and head home. TPMS is just a warning and doesn't interfere if you have it removed, only if they trip while driving will it impact (jaringly as I've described) you.

My '18 LCI is 100% stock sans RE71s and had the TPMS's removed entirely. Kept them for reinstallation should I ever decide to part ways.

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      10-04-2020, 12:28 PM   #188
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Originally Posted by Gusman1 View Post
What size supercar3s? Better overall or just better grip?



How do you get euro mdm and m4gts diff settings?
On the E46 I ran 245/40R18 front and 275/35R18 rear. The E46 is stuck with a really skinny front wheel (8"). RE71R's probably have a smidge more peak grip and definitely provide much more direct steering response and feedback, however, the Supercar3's are more consistent with a wider heat happy zone and they resist rollover MUCH better, allowing for much more effective tire life. As an autox practice/non-SRS-BZNS tire for a camber-limited car, I think the Supercar3 is now the best bet. If you want to win a National-level event, Yokohamas are what you want due to raw grip (very pricey though).

I didn't think much about it initially, but coding in different DSC and e-diff software settings is probably not allowed. If the software is already on the car from the factory and just needs to be enabled via off-the-shelf tools, then it's a bit of a gray area, but if you had to download the software to the car then it's against the rules.

As a potential competitor, I don't care much about the MDM stuff as the fastest guys are running DSC off I'm sure anyways. But the diff software could theoretically be a significant advantage (it's probably not in actuality).

Might be worth an explicit clarification from the Rules committee.
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      11-10-2020, 09:51 AM   #189
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Lots of good info in this thread, so rather than start a new one this seems like an appropriate place to mix-in M2C setup now that it's in BS as well. I'm shopping between the M2s and trying to make a guess which would be the best choice for BS in 2021. Despite the upgrades to the stability/predictability, power and brakes of the M2C it seems that the need to run 19" fronts really limits tire size/choice. My gut tells me the ability to run more front tire on an m2 > the on-paper power/handling improvements of the m2c... But a case can be made that drivability/predictability yields time in the real world too. I'm seeing talk about the Supra in lieu of the m2c being the next car for BS, which reinforces my thought. Unfortunately not having data from 2020 nats means this very much up for debate heading into 2021.

Anyone have experience with both or opinions on this topic? Seems like a lot of clubs out there are managing run enough events to let this play out in practice whereas in DC we didn't get one from SCCA at all.
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      11-10-2020, 10:07 AM   #190
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Originally Posted by Dean_Clevername View Post
Lots of good info in this thread, so rather than start a new one this seems like an appropriate place to mix-in M2C setup now that it's in BS as well. I'm shopping between the M2s and trying to make a guess which would be the best choice for BS in 2021. Despite the upgrades to the stability/predictability, power and brakes of the M2C it seems that the need to run 19" fronts really limits tire size/choice. My gut tells me the ability to run more front tire on an m2 > the on-paper power/handling improvements of the m2c... But a case can be made that drivability/predictability yields time in the real world too. I'm seeing talk about the Supra in lieu of the m2c being the next car for BS, which reinforces my thought. Unfortunately not having data from 2020 nats means this very much up for debate heading into 2021.

Anyone have experience with both or opinions on this topic? Seems like a lot of clubs out there are managing run enough events to let this play out in practice whereas in DC we didn't get one from SCCA at all.
I went from a pre-LCI M2 to an M2C. The limited tire selection in 19s is a constant headache. Keep in mind that with either, you have no place to run outside of BS. I have coilovers and camber plates now, and am running in a regional-only catchall class.
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      11-10-2020, 10:26 AM   #191
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As to tire choice, if the RE-71RS *ever* gets to the US (supposedly next year? it's available elsewhere in the world now), the Bridgestone Japan launch data showed that a 275/30-19 and 295/30-19 would be available sizes. Whether they bring these sizes to the US or not is unknown. Right now in Australia those sizes aren't listed as available yet (just 255/35-19 and 275/35-19 which are the sizes I'm using on the M2C in RE-71R form). Anyway, that might be an interesting tire and size choice in the near future. It's the replacement for the RE-71R.
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      11-10-2020, 11:58 AM   #192
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Keep in mind that with either, you have no place to run outside of BS. I have coilovers and camber plates now, and am running in a regional-only catchall class.
For sure, but that's the same classing headache with most cars I'm interested which have good power. Most small mods bump you to prepared which are pretty much empty here locally. I'm coming from a 996 C2 that went from buried in AS to the desert island of ASP with coilovers so the appeal of the M2 is keeping it as stock as possible aside while still being optimized for BS and also being able to run in S2 for TT just for fun. Haven't seen a lot of people messing different shocks on these in BS, so that's a plus honestly. Plenty of variables between my ears to manage from run to run, the less on the car to worry about the better haha
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      11-10-2020, 12:05 PM   #193
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As to tire choice, if the RE-71RS *ever* gets to the US (supposedly next year? it's available elsewhere in the world now), the Bridgestone Japan launch data showed that a 275/30-19 and 295/30-19 would be available sizes. Whether they bring these sizes to the US or not is unknown.
I am confident that the RE71RS will be announced for US sale in those sizes... 3 weeks after I purchase a non-comp specifically for tire availability reasons :B
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      12-11-2020, 11:42 AM   #194
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Hi everyone, new member here.

I am looking at getting an OG M2 for BS next year. Are DCT cars worth considering or should I look for a manual transmission?
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      12-11-2020, 05:50 PM   #195
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Hi everyone, new member here.

I am looking at getting an OG M2 for BS next year. Are DCT cars worth considering or should I look for a manual transmission?
Driver skill counts for more than DCT vs. 6MT. A DCT M2 took BS in our region last year.
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      12-12-2020, 01:59 AM   #196
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Driver skill counts for more than DCT vs. 6MT. A DCT M2 took BS in our region last year.
Thanks, so it's just a matter of preference then.
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      12-12-2020, 11:04 AM   #197
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Quote:
Originally Posted by Old Geezer View Post
Driver skill counts for more than DCT vs. 6MT. A DCT M2 took BS in our region last year.
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Thanks, so it's just a matter of preference then.
No question skill is a huge component. However, just note that DCT adds 55 lbs in a 3500lbs car, so results in a 1.6% reduction in power/weight ratio from an acceleration standpoint. Note 55lbs is BMW's quote on the increase for DCT, but Car and Driver measured it at 67lbs (M2 Comp tests).

Also consider launching and trying to achieve the best 60' time (or whatever initial launch interval you want to consider), where with a 6MT you have complete control over the engagement, weight transfer rate to rear tires versus power applied to them, etc. DCT 1st gear is really short, so hooking and controlling the launch can be challenging. This is probably the reason C&D was able to time a 3.9 sec to 60mph with the 6MT and 4.0 with the DCT M2 Comp.

Given that most autox courses result in 1 upshift and then 2nd gear the whole time, DCT disadvantages have the potential to be more meaningful. DCT has a shorter 1st and 2nd gear, so that might require 2-3 shifts in a DCT car where the 6MT can hang in 2nd as it has about a 12% longer 2nd gear.

All the above is in reference to the M2C but would imagine the OG DCT is a similar comparison.
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      12-20-2020, 03:15 PM   #198
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I'm late to the party, but I figured I would add to this DCT vs Manual discussion since I researched this issue thoroughly myself first on E92 M3 and then on this car.

DCT is a definite advantage on track because a manual clutch has a small interruption in power delivery every time you shift. Each shift loses a tenth or two which add up to a couple full seconds or so over the course of the entire track. However, manual cars gain some of that time back in the corners due to the ~40-60lbs (depending on the specific car) weight advantage of the manual. On any large track, the weight advantage does not do enough to offset the power interruption, and a DCT will be ~1 second/lap faster.

As the size the track decreases, the DCT advantage decreases, as more time is spent in turns versus the number of shifts on straightaways. However, one wrench in this is that DCT's allow shifting during turns, which means that DCT's can always be in the optimal part of the power band while manual shifters will often stay in a suboptimal gear in order to avoid a gear shift at an awkward time.

When you get down to an autocross size course, straights are effectively gone, removing the primary advantage of DCT's. However, the secondary advantage of shifting at awkward times remains. Most autocross courses can be comfortably driven in 2nd gear the entire time. However, some courses have slow corners that benefit from briefly shifting to 1st or straights just long enough to bounce off the limiter in 2nd. Most drivers don't bother shifting in those instances because the shift itself will negate any advantage in changing gears, but DCT drivers can shift without penalty.

Because autocross courses vary so wildly, it is impossible for anyone to say with certainty whether DCT or manual will be a definite advantage. One may be advantageous one day, while the other on the next. Because autocross courses are short, it is unlikely for the difference between DCT and manual to vary more than a tenth or two, and most are pretty close to a wash.

One final note. DCT cars tend to me more difficult to launch reliably, which only matters for SCCA ProSolo's. The issue is launch control is only available on the first run (most cars require more cooldown to use launch control again than what a ProSolo typically allows). Launching DCT's manually is a bit awkward because the computers dont like to quickly switch from N to D. If doing well at a ProSolo matters to you, that may increase the value of a manual.

ProSolo's aside, I believe DCT vs manual is driver preference for autocross. I myself got a DCT since a good example was locally available (saving me thousands of dollars in transportation) and it is a daily driver that my wife will borrow from time to time.
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