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      09-02-2023, 09:06 PM   #1
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M.1500.Z tinder profile… er M2 Competition build / track log

Preface
I’m coming up on completing 3 years of tracking and while it started as just having fun, trying to either will or spend my way to being faster, I’m beginning to think more seriously about the hobby. Life is short and whether you get 4 days or 40 days on track, it’s never enough. I think it’s time to start documenting the changes and progress and maybe it'll help some people along the way.

I’ve been in love with wheeled toys for the majority of my life. I have a lot of history from drifting old Toyotas, to spending time on motorbikes, or just enjoying self-powered thrills via cycling. I didn’t expect to fall this hard into tracking yet here I am—I should’ve known better.

Before I got the M2 Competition, I had a 2018 LCI M2 that I did European delivery with (maybe a post for a rainy day). That car was largely a street car that had tasteful modifications on in the name of Öhlins Road & Track dampers, Future Classic wheel spacers, and an M Performance exhaust. Late 2020, during the pandemic, I decided I should do a track day and added Recaro Profis, Pagid RSL-29 pads, and SRF. One weekend at Circuit of the Americas in it and I was hooked. It was unceremoniously [and sadly] traded in for an M2 Competition. Before the M2, I had an E39 M5 (yet another story for a rainy day)—bit of a BMW loyalist.



Pragmatism, maybe or maybe not
As this journey has progressed, I’ve come to form a few guiding principles—some of which are because I bought it new (dumb) and others are just because I take what I jokingly call a pragmatic approach and try to do more with less. Jokingly because as you’ll see, I also tend to believe in buy once, cry once and that doesn’t always lead to pragmatic financial choices. If I were to lay these principles out, they would be:
  • Reliability is key
  • Don’t fuck the drivetrain warranty
  • Go fast with less grip (aka avoid hoosiers/scrubs)
  • Save weight, but not at the expense of reliability or quality
  • Add power as a last resort
  • Any aero should be well thought out and be aesthetically clean
  • Channel the touring car spirit

V 01 | Base
Since I had that previous M2, I carried over the Öhlins and Recaros and again went with Pagid RSL-29 pads for the Competition’s first weekend on track. I may have jumped the gun and missed the opportunity to learn the car stock, but that’s OK. I ran Goodyear Supercar 3 tires in stock 245/265 sizes and got accustomed to the car like this. I ran the car like this for 3 weekends at COTA and thought it was extremely capable but again left time on the table before moving on, but not before adding an M2 CS Racing front lip.





Because the knock back had become somewhat annoying, I started having thoughts—the kind of thoughts that lead you to spend money on fancy tings. From driving the car and having friends who tracked their E46s a lot, I had devised some ideas of what I wanted next:
  • More front end grip
  • The ability to run 18s
  • Cool wheels

I just happened to have a motorcycle sitting in my garage that would cover a large part of those costs…

V 01.5 | Going square and setting goals
Using some alchemy, I transformed the motorcycle into an AP 9668 “little-big” brake kit. And a set of BBS RI-As in diamond silver. It wasn’t 100% straightforward though, more on that in a moment.

The AP 9668 is not a cheap bit of kit but it fits squarely into my buy once, cry once philosophy. It also happens to meet my principles of saving weight (nearly 24 pounds unsprung weight), and reliability. The 25mm thick pads are almost a must-have in my opinion and the quick change clip makes pad swaps, well, quick. I started with the DS3.12 pad and just cannot shake my love for this pad despite their cost.

I wish that the wheels would’ve been as simple a decision as the brakes. I really wanted to run a 10.5” wheel square and have it be rotatable, but the M2 makes life pretty difficult in this regard. Part of this is also dependent on what dampers you’re running and at the time, my Road & Track setup wasn’t great. In terms of offset, what’s good at the front often doesn’t fit the rear and vice versa. Complicating matters is that I wanted to run a forged single-piece wheel for weight and strength and it had to look good to my eyes which had led me to BBS RI-As. I ended up going with a staggered setup of 18x10 +25 in the front and 18x10.5 +37 in the rear but with a square 275/35-18 tire—at the time another set of Goodyear Supercar 3s. Additionally, the car needed to run a 10mm front spacer for clearance because of the long front spring on the Öhlins.



I feel like this was a sweet spot for the car, providing a much more neutral feel overall. The additional front-end grip, while improving the car pretty much everywhere, provided significant gains in trail braking and carrying mid-corner speed. Seconds seemed to fall off my lap times at COTA and I think it goes to show what the car is capable of with a conservative tire size and some dampers. It’s a shame that you can’t run 18s out of the box.

Throughout this half-stage, I added a few items and played with ride heights largely to get in and out of my driveway and clear spring perches, and just tried to drive the car. Took a trip to Eagles Canyon Raceway and began to realize I needed to sit a bit higher in the car for vision.



Items added throughout v_01.5
  • SPL Parts caster adjustable caster rod monoballs
  • M2 CS Racing front and rear sway bars
  • SPL Parts sway bar end links

It was at some point in this stage that I decided to set a goal. The goal was a COTA lap-time since that’s the track I [sadly] drove almost exclusively and it’s a time that seems to separate groups. I also began to look more at the data from my Aim Solo 2 DL.

The goal
  • Sub 2:30
  • Stock power
  • No aero
  • 275 square 200tw tires

V 02 | Clubsport and beyond (whatever that means)
Adding a roll bar seems like good major version shift—it represents a shift toward “clubsport” at the expense of some street comfort. As mentioned above, my trip to Eagles Canyon Raceway was a bit of a wakeup in terms of my seat height due to more blind corners and elevation changes than COTA and I was struggling with my vision from almost sitting on the floor—I’m not very tall and a lot of my height is leg. In addition, the stock 3 point belt was not providing me the support I wanted even with the Recaro Profi. I started working out how to improve my seating position and getting legitimate belts for the car and that meant adding a roll bar.

Bit of a story here. In the early 2000s I worked for SPL Parts. At the time we were largely a Nissan shop and it was a 2-man operation except during the summer when usually another young car kid would come and intern. A friend from the local drift scene worked with us for a summer and really enjoyed the ideas of fabricating. I can’t say if this is where it started for him or not, but he would go on to work at a couple other shops, working on his craft and eventually start his own shop Walker Pro Motorsport. He truly does fantastic work and it was a no-brainer to hit him up when it came to a roll bar. I need to get some nice photos because the fitment is so tight and nice.



To go along with the bar, I’d bought some 2 series manual sliders from eBay, some Brey Krause adapters, and Schroth harnesses. Everything was installed at WPM and I was ready to go. Unfortunately, I’m still not satisfied with the seats here—in order to fit the sub-strap bar, the seat has to be raised in the front creating a bit too much lean and I don’t want to raise the rear any higher. The search for perfect seat mounts continues.

In the chase for times, I’d started thinking about how I could improve the drivability and consistency of the car. I wanted to run more spring rate but also gain some wheel clearance and ditch my 10mm front spacer. After some searching online and a lengthy call with 3DM Motorsport, I came to the realization that my Öhlins Road & Track dampers wouldn’t be ideal (or at least would require some hefty work). I have a writeup here about how I ended up with my current Öhlins TTX 2 ways. I’d also added the rear AP 9451 brake kit to drop some additional weight and match the front.



The car has been at this stage for about a year and change, and aside from picking up an Akrapovic Evo setup that popped up locally, I haven’t made any changes. The car is still extremely neutral and I have a 100% rating on peoplewhohavedrivenmycar.com. It's continues to surprise people on track with how quick the car is given it's tire size and power. Not only is the car fun and fulfilling but because of the choices in parts and lack of additional power, it's extremely consistent.

I’ve taken the car to a couple more tracks and am still learning and having fun. Additionally I’ve hit my goal of going sub-2:30 at COTA with a 2:29.3 and will keep pushing. Lastly, I’ve begun using an online coach with Blayze and had a couple sessions which I think will pay dividends in the long run.







What’s to come
As I’ve been going through this journey, I’ve gotten pretty keen on improving as a driver and have decided to look into doing Time Trials with NASA. Ultimately, whether with this car or another one, I would like to do some wheel to wheel racing. As much as I relish going faster, Time Trials and Time Attack aren’t what speaks to me. But, to that point, I’d like to continue to push the F87 platform and see what may happen as it’s quite rewarding. I also have plenty of questions about how competitive it can actually be considering it’s essentially an improved E46 (stiffer with more power) and those cars are still extremely competent.


Current parts list Updated 08.02.2023

Powertrain
  • Akrapovic Evolution system

Suspension
  • 3DM Öhlins TTX 2 ways
  • Vorshlag camber plates
  • M2 CS Racing front and rear sway bars
  • SPL Parts sway bar endlinks
  • SPL Parts adjustable caster arm monoballs
  • SPL Parts rear toe arms

Wheels and brakes
  • BBS RI-A 18x10 +25 fr / 18x10.5 +37 rr
  • Essex AP Racing 9668 front brake kit
  • Essex AP Racing 9451 rear brake kit

Interior
  • Recaro Profi SPG
  • Brey Krause mounts to stock 2 series manual adapters
  • Schroth Flexi 2x2 harnesses
  • Walker Pro Motorsport roll bar

Data / coding
  • Aim Solo 2 DL CAN bus
  • Aim Smartycam 3 Sport
  • Daap brake coding
  • Euro MDM
  • GTS differential coding

Exterior
  • M2 CS Racing front lip spoiler
  • M2 CS Racing rear wing
  • IND tow hook covers with Fall Line tow straps
  • Goldenwrench Blackline rear reflector covers


Links to items/places
SPL Parts | maker of great suspension components
Walker Pro Motorsport | Top-level fabrication services
3DM Motorsport | The Öhlins shop for BMWs and beyond
Soulspeed Performance | Alignments and wheel services for 20 years in the Austin area
Blayze.io | Online driver coaching and analysis

Last edited by M1500Z; 03-29-2024 at 02:40 PM..
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      09-03-2023, 02:57 PM   #2
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this car is going to end up all gutted and with a big wang come next year
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      09-04-2023, 06:16 AM   #3
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Nice write up. Enjoyed the read and the progress!
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      09-04-2023, 04:02 PM   #4
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Quote:
Originally Posted by swagon View Post
this car is going to end up all gutted and with a big wang come next year
Ha, perhaps. I have a CS Racing wing for the car that's been sitting in a box. I've slowly been looking for a spare Alpine White trunk lid or a stock-appearing lightweight trunk lid to put holes in. More on that soon though.
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      09-04-2023, 06:39 PM   #5
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Great post. Lovely car. Love seeing the various folks on here on their own F87 track journey. The knowledge that gets shared is incredible.

I’m interested to hear your thoughts on the transition to the TTX, specifically how they compare to a less expensive unit like the R&T. Also, any intention on playing with spring rates at all? How have they been to dial in?

And the swaybars… curious about the swaybars and their impact.

Last edited by ThreeStripes; 09-04-2023 at 06:44 PM..
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      09-04-2023, 08:56 PM   #6
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I'm always interested in how much time it takes to set up a 3 way? Is there one set of settings that do all, or must you set up per track?
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      09-06-2023, 02:35 PM   #7
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Quote:
Originally Posted by ThreeStripes View Post
Great post. Lovely car. Love seeing the various folks on here on their own F87 track journey. The knowledge that gets shared is incredible.

I’m interested to hear your thoughts on the transition to the TTX, specifically how they compare to a less expensive unit like the R&T. Also, any intention on playing with spring rates at all? How have they been to dial in?

And the swaybars… curious about the swaybars and their impact.
First of all, thanks. Hopefully through all of this, I can add to that knowledge.

It's been a while since I swapped to the TTX and the thread linked in the post is still relevant regarding my thoughts and perceptions. But I think what it comes down to is just the finer control you get. I lopped 1s off my lap time immediately but the biggest change seemed to be control of the car and consistency.

The R&T setup (which I ran with a shorter 560lb front spring) needed to be "clamped down" with the dampers only a few clicks from full stiff for me to get the car how I wanted and it would dance around a bit more which, for me, led to more inconsistency. I am not a damper wizard but you can definitely feel how the knobs change the dynamics of the car. I found good settings not too far off the out of the box settings. It helps to read a bit about damper tuning as well.

I don't believe I'll be touching spring rates at this point. I'm pretty in-line with what most F8X cars are running and what Barry @ 3DM recommended to me. The 14k/12k (784lb/672lb) rates bring my estimated freq. to 2.91hz/2.40hz respectively.

For the sway bars, they're at the soft setting (there are only soft/hard) and they just help to keep the car flatter which I like. I will likely move both to hard when I corner balance soon and see if that makes much of a change—mostly to see if it might improve front tire wear. What I never did was run them at the hard setting with the R&Ts to see if that might have allowed me to back the dampers off a little bit.

Quote:
Originally Posted by medphysdave View Post
I'm always interested in how much time it takes to set up a 3 way? Is there one set of settings that do all, or must you set up per track?
These are 2-way and I don't make too many adjustments at the track to optimize at this point because my settings from COTA have largely worked at the other 2 tracks I've driven them on. Also low-speed is mostly about driver inputs so I haven't felt I've been anywhere yet where the car is not in-sync with what I'm asking of it.
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      09-06-2023, 02:45 PM   #8
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Thanks for sharing. I like this well sorted approach to your goals. In the coding you have Euro MDM. Did you notice a difference when going from stock to Euro? I run MDM at the track in the CS and rarely do I get interference. I've contemplated turning everything off, but a Performance Center instructor suggested there is no point if I'm doing my part to drive the right line. I'm curious if you keep it in MDM, switch it off? If you switched it off what was your tipping point, or where did you notice MDM holding you back?
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      09-06-2023, 04:34 PM   #9
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Quote:
Originally Posted by medphysdave View Post
Thanks for sharing. I like this well sorted approach to your goals. In the coding you have Euro MDM. Did you notice a difference when going from stock to Euro? I run MDM at the track in the CS and rarely do I get interference. I've contemplated turning everything off, but a Performance Center instructor suggested there is no point if I'm doing my part to drive the right line. I'm curious if you keep it in MDM, switch it off? If you switched it off what was your tipping point, or where did you notice MDM holding you back?
I can speak to the difference on the street: it’s significant. 2nd gear powerslides would trigger intervention of MDM with far less angle and more abruptly. Updated MDM to CS aka euro setting and the difference was startling. It will let you nearly loop it before shutting down the party.

Never tracked in MDM pre-coding but have post and when I nearly looped it in a hairpin on track it again let the car get beyond entirely sideways before saving my ass. Can’t speak to what the stock MDM parameter allows but expect it would be far more conservative on track as I experienced on the street.

Last edited by ThreeStripes; 09-06-2023 at 06:07 PM..
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      09-06-2023, 06:01 PM   #10
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Quote:
Originally Posted by M1500Z View Post
For the sway bars, they're at the soft setting (there are only soft/hard) and they just help to keep the car flatter which I like. I will likely move both to hard when I corner balance soon and see if that makes much of a change—mostly to see if it might improve front tire wear. What I never did was run them at the hard setting with the R&Ts to see if that might have allowed me to back the dampers off a little bit.
Thanks for the additional thoughts. This piece in particular is something that has me curious.

I’m interested as I’m currently on TCK doubles in the rear and singles up front. Having experienced top shelf damping via Nitron and MCS, I have a growing appreciation for what they deliver over more middle of the road options like a TCK or Ohlins R&T but wonder if I hold off upgrading in favor of CSR sways.

Dropping the rear sub-frame sounds like it may be worth it. I don’t think they’ll impact ride comfort much. TC Kline said they would when I asked his thoughts, but I’m not convinced.

Last edited by ThreeStripes; 09-06-2023 at 06:11 PM..
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      09-06-2023, 06:34 PM   #11
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Quote:
Originally Posted by ThreeStripes View Post
Thanks for the additional thoughts. This piece in particular is something that has me curious.

I’m interested as I’m currently on TCK doubles in the rear and singles up front. Having experienced top shelf damping via Nitron and MCS, I have a growing appreciation for what they deliver over more middle of the road options like a TCK or Ohlins R&T but wonder if I hold off upgrading in favor of CSR sways.

Dropping the rear sub-frame sounds like it may be worth it. I don’t think they’ll impact ride comfort much. TC Kline said they would when I asked his thoughts, but I’m not convinced.
I think it was FaRKle! that may have put out a YouTube video with Shaike that showed how little the rear bar is doing on the M2. Unsure how much this changes with the rear CSR bar. My thought is that the rear bar isn't worth the hassle. Seems the rear toe arms provide a lot of bang for the buck by getting rid of the rear end squirm. I have a CSR front bar going in shortly, but leaving the rear alone.
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      09-07-2023, 08:18 PM   #12
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Quote:
Originally Posted by medphysdave View Post
Thanks for sharing. I like this well sorted approach to your goals. In the coding you have Euro MDM. Did you notice a difference when going from stock to Euro? I run MDM at the track in the CS and rarely do I get interference. I've contemplated turning everything off, but a Performance Center instructor suggested there is no point if I'm doing my part to drive the right line. I'm curious if you keep it in MDM, switch it off? If you switched it off what was your tipping point, or where did you notice MDM holding you back?
I never took the car to the track prior to coding Euro MDM so can't comment on the differences. There have been times where I'd rather have been able to stay in the throttle and ride the slide rather than being interrupted by MDM. Being more intrusive (US MDM) would certainly be a detriment. I've turned it off at small club tracks and not really noticed a difference.

I don't fully disagree with your instructor, but to my experience above, there are times where you may exceed MDM's threshold for slip and have it intervene when in reality you'd only have had a little slide or understeer and gone quicker. I've also had it potentially save my ass before.

Quote:
Originally Posted by ThreeStripes View Post
Thanks for the additional thoughts. This piece in particular is something that has me curious.

I’m interested as I’m currently on TCK doubles in the rear and singles up front. Having experienced top shelf damping via Nitron and MCS, I have a growing appreciation for what they deliver over more middle of the road options like a TCK or Ohlins R&T but wonder if I hold off upgrading in favor of CSR sways.

Dropping the rear sub-frame sounds like it may be worth it. I don’t think they’ll impact ride comfort much. TC Kline said they would when I asked his thoughts, but I’m not convinced.
You don't have to drop the subframe—it can be lowered enough on the studs to wriggle the old one out and new one in and it's helpful if you have an aftermarket exhaust that doesn't have to be supported. It could be possible with quickjacks and a transmission jack to lower/raise the subframe. I believe the subframe is "keyed" so it goes right back where it was.

Sways are part of the equation for roll-stiffness (they also affect pitch). I was effectively using my dampers to try and keep the car flat by excessively slowing the valving, e.g. not their intended usage. Part of me wonders if I'd tried them in the stiff setting, I may have had a little more roll stiffness and backed the dampers off, but in reality I doubt it because it's a pretty marginal increase. Personally, I would never do just a front bar—just seems like you're asking for push.

Quote:
Originally Posted by medphysdave View Post
I think it was FaRKle! that may have put out a YouTube video with Shaike that showed how little the rear bar is doing on the M2. Unsure how much this changes with the rear CSR bar. My thought is that the rear bar isn't worth the hassle. Seems the rear toe arms provide a lot of bang for the buck by getting rid of the rear end squirm. I have a CSR front bar going in shortly, but leaving the rear alone.
I'm not a suspension engineer so take this with a grain of salt. If you're taking a car that has understeer engineered into it and increasing front-roll stiffness without increasing the rear, then it seems like you'll end up with even more understeer. I know it's a strut front and you want to keep the camber from going negative, but I still think the rear should be increased in kind. I'm simplifying it, but that's my general opinion.
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      09-07-2023, 10:06 PM   #13
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Within the past month I've begun to look at the NASA TT classification system and trying to work out where the M2 would fit. NASA TX has a very competitive TT3 group and I had been hoping to not be in it. TL;DR Looks like I'll be in TT3. Shit.

NASA uses a weight to horsepower ratio for classification. They take the base number and have modifiers on top of that that can add or subtract to that number. My hope was the weight of the M2 would offset its power, then with no aero and a street tire, I could squeak by in TT4. TT3 requires you to be above 10:1 with modifiers and TT4 is 12:1.

For power, the car has to do 3 pulls on a dynojet with SAE correction and smoothness level of 5. This ideally gives a relatively good comparison vehicle to vehicle. I figured this is where I should start and took the car to a local shop to get it dynoed.





Results look pretty healthy to me. This is a stock S55 with an Akrapovic Evo system. I find it pretty amazing how consistent all the pulls are with only the torque dropping off a little. For NASA's classing system, they use a calculated average HP which for me came out to 387avg hp. I previously had the car weighed and corner balanced with 165lbs of driver ballast and nearly a full tank of fuel, it came out to 3705lbs.

At that weight and power, that's a baseline of 9.6:1 lbs per HP. Here's how, best I can tell, the modifiers calculate out:
  • +1 for running RE-71RS
  • + .3for a tire that should measure less than 282mm
  • + .4 for a car that is 3601lbs or more
  • + .4 for BTM or no aero
  • - .5 for factory DCT transmission

All of this brings me to a modified lbs to HP of 11.2:1 which is not great. NASA seems to favor 2 things—Hoosiers and aero, neither of which I'm going to have immediately, and heavily disadvantage the DCT and power. The rules around aero appear relaxed, so a large splitter and swan-neck wing are penalized as much as some basic OEM+ style pieces. All of this is apparent in the cars at the pointy end of the field—detuned Corvettes and M3s that run large splitters and wings on hoosiers. Of course have good drivers as well.

My next steps are clear. I've got to get the car weighed and corner balanced again and see how much weight I may be able to drop. I'll continue to look for a trunk lid to put my CS Racing wing on—it's likely to help a little bit but won't be nearly as effective as the larger wings on many of the cars. I've also been wanting to either make or find a true splitter that, even if just flat, goes to the front axle. Mostly, I'll try to get to both of the remaining NASA events and just drive the car and see where I land—I've already got some fresh RE-71RS sitting in the garage.
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      10-06-2023, 01:12 PM   #14
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Had the car in the shop for a few things yesterday—all basic. I needed to weigh the car to figure out my minimum weight for NASA and re-corner balance since I'd added the Akrapovic evo system.

Driving the car down to the shop got the car down to ~50% tank (MyBMW reporting 6 gal) just as I'd hoped. I don't want to put a ton of effort into fuel loads for TT sessions, but I know I can't run the car much under 25% tank and figured corner balancing at 50% would keep it from too much dynamic shift.

Total weight 3619
  • ~50% fuel load
  • 160 lb driver weight
  • 50.01% cross weight
  • 53/47 front-rear weight dist.

This leaves me with some wiggle room in the future to add a splitter and wing and/or maybe Hoosiers.

Re-aligned the car keeping my previous specs and then had the swaybars adjusted to the stiff setting front and rear. Next stop should be MSR Cresson at the end of the month!
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      10-06-2023, 03:36 PM   #15
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Quote:
Originally Posted by M1500Z View Post
Had the car in the shop for a few things yesterday—all basic. I needed to weigh the car to figure out my minimum weight for NASA and re-corner balance since I'd added the Akrapovic evo system.

Driving the car down to the shop got the car down to ~50% tank (MyBMW reporting 6 gal) just as I'd hoped. I don't want to put a ton of effort into fuel loads for TT sessions, but I know I can't run the car much under 25% tank and figured corner balancing at 50% would keep it from too much dynamic shift.

Total weight 3619
  • ~50% fuel load
  • 160 lb driver weight
  • 50.01% cross weight
  • 53/47 front-rear weight dist.

This leaves me with some wiggle room in the future to add a splitter and wing and/or maybe Hoosiers.

Re-aligned the car keeping my previous specs and then had the swaybars adjusted to the stiff setting front and rear. Next stop should be MSR Cresson at the end of the month!
3460 isn't bad at all.
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      10-09-2023, 11:13 AM   #16
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3460 isn't bad at all.
No, it's not terrible by any means. I'll probably pick up a lightweight battery in the not-too-distant future to shave another 35-40 lbs, but not sure what I'd do next to drop additional weight. I'll likely hit the point of diminishing returns pretty quickly.
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      10-09-2023, 11:27 AM   #17
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I'm not familiar with the rules - do they allow you to run a a full tank? If not, how much time does a half a tank get you? 2 sessions?
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      10-09-2023, 02:34 PM   #18
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No, it's not terrible by any means. I'll probably pick up a lightweight battery in the not-too-distant future to shave another 35-40 lbs, but not sure what I'd do next to drop additional weight. I'll likely hit the point of diminishing returns pretty quickly.
Pretty much got wheels, brakes, seats, rear seat delete, battery, and exhaust. After that it gets expensive.
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      10-09-2023, 02:41 PM   #19
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I'm not familiar with the rules - do they allow you to run a a full tank? If not, how much time does a half a tank get you? 2 sessions?
You can run however much gas you want. I haven't found my fuel level to make much of a difference, so now I usually run with a full tank so that I don't have to worry about starvation issues.
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      10-10-2023, 06:53 PM   #20
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You can run however much gas you want. I haven't found my fuel level to make much of a difference, so now I usually run with a full tank so that I don't have to worry about starvation issues.
+1 on this. You can chew threw a quarter tank of gas very quickly. I try to fill it when I hit half tank. No noticed difference from me between half and full.
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      10-11-2023, 11:55 AM   #21
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I'm not familiar with the rules - do they allow you to run a a full tank? If not, how much time does a half a tank get you? 2 sessions?
For DEs I typically start with a full tank and refuel after every session or every other session. If there's a good bit of full throttle, I can go through about 30-40% of a tank in a 25 min session. When I run COTA with Chin who does a 40 min session and an hour-long happy hour, I have to go out with a full tank or I'll get the light in the middle of the session.

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Originally Posted by jwr9152 View Post
You can run however much gas you want. I haven't found my fuel level to make much of a difference, so now I usually run with a full tank so that I don't have to worry about starvation issues.
I don't feel the difference, but the car does seem to be quicker with lower fuel weights. Since TT sessions are pretty quick, I'll go out with less fuel and try to be at minimum weight. I don't think I've run into starvation issues but I try not to run the car under 25%. Usually I'll get a warning saying I've only got 10 miles till empty even though the car has ~25-30% fuel left (after it settles).

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Originally Posted by jwr9152 View Post
Pretty much got wheels, brakes, seats, rear seat delete, battery, and exhaust. After that it gets expensive.
Yep, got all the things pretty much and unless I commit to owning this car forever, I don't see a lot of value in chasing weight much further.
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      12-11-2023, 04:20 PM   #22
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Since my last post, I ran the last 2 events of the NASA TX season. I've learned a few things, had a lot of fun, and looking forward to doing more next season.

Oct. 2023 | MSR Cresson 1.7 CCW
October's event was 2 days at MSR Cresson—a track I had never driven but was looking forward to. It's short but looks quick, and I'd heard it was a good track to push at since going off has relatively little consequence. Leading up to the weekend, the rain forecast kept increasing until finally I came to grips with the fact that it was going to be cold and wet. That would be an understatement.

The rain began on my drive up to Cresson. I was on brand new RE-71RS thankfully, because even with full tread, there was enough water to get some hydroplaning in several places. More rain would come down overnight and into the morning—enough to create what was essentially a low-water crossing in a couple of corners (Big Bend/Little Bend). We wouldn't see a complete dry line all weekend. On top of all of this, MSR Cresson is known for being one of the slickest tracks in the wet. New goals—learn the track at a low pace, learn the TT processes, and don't find myself needing to power wash mud off the car.

First session example of how much water there was (and this was after the track had actually drained a little).



Sunday was more of the same, just much colder with temps hovering around the 40s all day, and wind to boot. The track was still incredibly slick and while I was quicker vs. some of the competition in the full wet, as parts dried out here and there, track knowledge and skill won out. It didn't help that I was on stiff sway settings, but I'd left the car in the softer damper settings I drove up on. In the vid, you can see how nice and slippery it was—I was just playing TC hero all weekend.



For TT, all cars must go straight to impound for weight check. Learning that process was helpful, additionally I learned that I need to claim a lower minimum weight and will change this for next season—I didn't get DQ'd but came within 10lb. The worst thing about impound is it's basically impossible to check tire pressures hot so it's a bit of a guessing game. Overall the weekend was a wash in terms of driving but useful nonetheless.


Dec. 2023 | Eagles Canyon Raceway
Last weekend was the final event of the NASA TX season at Eagles Canyon Raceway—another decent drive-to event for me. I was really looking forward to this one since I'd only been to ECR once prior and really enjoyed the track. This time I would have added grip through dampers and RE-71RS, and be sitting a little higher to better visually handle the changes in elevation (see first post—I'm not that short, I swear).

ECR is a really great track—flowing with elevation and the pavement is smooth with tame exit curbing. One of the characteristics is multiple double-apex corners which makes for a fun challenge of minimizing the number of steering inputs or adjustments after entry.

Previously I'd run a best time of 2:11.4 or so and since this was going to be a dry weekend, my goal was simply to improve upon that and then see how I stack up. There were 4 cars in the TT3 field and I was... the heaviest car with the most power, the only car without any aero modifications, and 1 of 2 cars on street tires.

First session out was warmup—took 1s off the time pretty much immediately trying to get a feel for the track again... things are off to a good start or are they. I'm way off the pace for my class—8 s off making 3rd place uncomfortable. That answered the competitive question pretty quickly, so back to work on competing against myself.

The second session got off to a rough start with confusion about start times due to the schedule being 15 min behind but then being caught up without a notification. I had to go out after the outlap and behind the cars in the slower TT classes, get tires and brakes up to temp and then get it. All in all this was actually fun for me because I like driving around other cars, but it did mean that my fastest lap (another 1s off) was actually set with traffic and 350Z spinning. Now my time is 2:09.8 but my theoretical is a a 2:08.1. Following that session, a surprise rain shower would basically end any opportunity for progression the rest of the day.

Sunday morning came and along with some very low temps—my car showed 28ºF on the way to the track. Heading out to grid with nearly freezing temps and concerns the dew had frozen to the curbs, I don't think anyone expected this session to be the fastest of the day. We quickly realized the track was surprisingly quick and this would be my quickest recorded TT lap at 2:08.0 (transponder time of 2:07.9—the transponder pickup is in a different location than AIM uses). In the end, the results look like this:
  1. 1:58.993 | E92 M3—very well driven and detuned on slicks with aero
  2. 2:01.647 | Evo IX—weight reduction+power on RE-71RS with aero
  3. 2:02.428 | C7 Grand Sport—detuned on [I think] A7s with aero
  4. 2:07.971 | A humble M2 comp on RE-71RS



I would end my day playing a little with damper settings and running a hair quicker during sundown and a theoretical best of 2:07.4. I had been on the out of the box damper settings all weekend and found adding a couple clicks of rebound equally front and rear got the car largely where I'd want it. All in all it was a great weekend and I have some thinking to do over the winter—a future post surely.





Right now, my priority is still to drive more and drive better—this is the largest disparity between myself and the other competitors in my class and I'll continue with my coaching through Blayze. I'm sure tire and aero would help, and weighing in at a portly 3600ish lbs while only on a 275 tire is going to be difficult to overcome, but I'd rather work on skill than modifications at this point. Plus, street tires are cheaper and better accommodate driving to events and changes in conditions.

Now onward to the home track (COTA) for a DE weekend to round out the year.

Last edited by M1500Z; 12-11-2023 at 05:35 PM..
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