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      06-20-2020, 09:44 AM   #1
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Track report



Especially as more GTS's make their way into enthusiast hands, figure I'll start an ongoing track journal with my experiences, findings, and (I guess) mods.

I'm at track day 4 as of this post. Day 1 was wet, day 2 I chunked my front Cup 2's after a few hot laps, day 3 was a traffic jam.

Our first post-COVID track day of the year was pretty packed as well, but managed a bit of clear running.



Current "build" status: Ground Control camber plates, factory lowered ride height, Profi + 6 pt, and new for this latest event, Goodyear Eagle F1 Supercar 3R in OE sizes. (Tire Rack happened to have just 2 of each size on a random tire check, so I totally impulse purchased. Those familiar with my contributions around here know that I'm unabashedly pro-Camaro. Couldn't turn down the opportunity for some NASCAR rubber on my M4!)

I'm boring, stick to my usual, and plan to run the GTS almost exclusively at Gingerman Raceway, so development info/data will be pretty consistent.



Track day 4 setup and observations --

- In an effort to sharpen up the front end/turn in, made a couple of tweaks to BMW's suggested track damper settings. Went from 2 clicks open to 1 click open on front low speed compression, and from 4 clicks open to 2 clicks open on rear rebound. That definitely livened up the back end, so after session two I adjusted back 1 to 3 clicks open rear rebound. Really nice balance, better exit traction. Power down out of turn 10 onto the back straight, for example, was pretty much ideal.

- The carbon ceramics are incredible. The only stock BMW system that I've ever found legitimately ready for track use. But, they're not going to make it long-term. If it's not one thing it's another with BMW brakes… C'mon boys.

I was thinking I'd have them refurbished every couple of years by a reputable Euro co., but the discs are already showing concerning wear and I'm not yet through pad set 1. Will likely swap for AP Racing before next event.



- Supercar 3R are excellent, user friendly. Don't take very long to warm up, durable intra-session. Fast, but maybe not quite as fast as anticipated as compared to the star spec Cup 2's.

My best in entirely stock form, lowered ride height, Cup 2 (no camber plates), and sliding around in the driver's seat was a 1:38.9. But limited running because, yeah, they chunked that day. Believe the car is probably capable of mid to low 38's in stock form with Cup 2. 37's would be tough.

Best lap with the 3R was a 1:37.9 (best rolling 1:37.8). On the lap below I lost about two-tenths in turn 1, carried too much speed in and had to back off throttle at exit. At other points in the day I was up as much as four-tenths on the 37.9 before hitting traffic, etc. Best theoretical according to a collection of my best laps and sectors is a 37.2 per Solo 2. In ideal conditions, add a corner balance, drop a bit of weight (hmmm, passenger seat maybe), send it into 11 (always leave a couple tenths there because wall), might be able to touch 36.

Peg the 3R at not quite 1.5 seconds faster than Cup 2 around Gingerman's 2.14 mls. About on par with some of the more aggressive Cup 2 variants, e.g., certain GM specs.

Later in the day I was halfway down the back straight when it cut power due to low fuel -- 1/8 tank left, but apparently the car cuts power based upon range when it hits 18 miles?? So, that's something new that I learned.

Even with its flaws, absolutely love the GTS. It's such a wicked and fun machine. The stuff dreams are made of for someone who used to chase down E36 M3's in teenage years just to get a look.





Surprised how well the sound came through on the windshield mounted gopro. Can hear just about every brush of the throttle w/ headphones, car is so damn loud.

More to come.







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Last edited by FormulaMMM; 06-20-2020 at 06:28 PM.. Reason: photos
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      06-20-2020, 04:44 PM   #2
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The star spec cup 2 issues are a bummer. I chunked the fronts within 48 miles in track, so about half way through the second session of the day.

Good to hear the 3r's work well!

You'll love the AP set up. I really liked the stopping power and absolute rock solid pedal throughout the whole session with the ceramics but the AP's are better in every way. Equivalent stopping power but way better feel than the CCB's. They're a win-win in my opinion.

Can't wait to see how the car improves with some tweaking and more familiarity. Awesome thread!
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      06-20-2020, 05:18 PM   #3
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Quote:
Originally Posted by Lienrocs View Post
The star spec cup 2 issues are a bummer. I chunked the fronts within 48 miles in track, so about half way through the second session of the day.

Good to hear the 3r's work well!

You'll love the AP set up. I really liked the stopping power and absolute rock solid pedal throughout the whole session with the ceramics but the AP's are better in every way. Equivalent stopping power but way better feel than the CCB's. They're a win-win in my opinion.

Can't wait to see how the car improves with some tweaking and more familiarity. Awesome thread!
Sweet, you running the 9668 kit? No clearance issues with the factory wheels? Calipers look really wide side by side with the stock M calipers.

Yes, 3R, Trofeo R, Z06 Cup 2 spec, M should have thrown caution to the wind and fitted a more aggressive tread & compound.

Fits their sort of mismatched approach for the U.S. market. Roll cage, but no shoulder harness holes. 3 ways with Cup 2, but not a version that's durable. Carbon ceramics, but apparently they failed to check the box for maximum durability with Brembo. (Have more than twice as many dry sessions in my Z/28 where I was harder on the brakes, no wear issues.)

Oh well.. Juice is worth the squeeze, a few mods away from being just about ideal.
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      06-20-2020, 09:51 PM   #4
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Quote:
Originally Posted by FormulaMMM View Post
Quote:
Originally Posted by Lienrocs View Post
The star spec cup 2 issues are a bummer. I chunked the fronts within 48 miles in track, so about half way through the second session of the day.

Good to hear the 3r's work well!

You'll love the AP set up. I really liked the stopping power and absolute rock solid pedal throughout the whole session with the ceramics but the AP's are better in every way. Equivalent stopping power but way better feel than the CCB's. They're a win-win in my opinion.

Can't wait to see how the car improves with some tweaking and more familiarity. Awesome thread!
Sweet, you running the 9668 kit? No clearance issues with the factory wheels? Calipers look really wide side by side with the stock M calipers.

Yes, 3R, Trofeo R, Z06 Cup 2 spec, M should have thrown caution to the wind and fitted a more aggressive tread & compound.

Fits their sort of mismatched approach for the U.S. market. Roll cage, but no shoulder harness holes. 3 ways with Cup 2, but not a version that's durable. Carbon ceramics, but apparently they failed to check the box for maximum durability with Brembo. (Have more than twice as many dry sessions in my Z/28 where I was harder on the brakes, no wear issues.)

Oh well.. Juice is worth the squeeze, a few mods away from being just about ideal.
The 9668's clear the stock wheels with literal inches to spare. I can fit my whole hand between the spokes and caliper and unless you get a boulder between the barrel and caliper you don't have to worry about grooving the front wheels either!

Agreed. BMW made some odd choices with the GTS but when you get it dialed it's sublime.
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      06-21-2020, 06:04 PM   #5
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I hope to see how this pans out. I will try to get a couple of track days (west coast) myself in my GTS but i think this will be far and few between. I going to leave mine rather stock. Other than dedicated rims tires(apex), ill probably switch to newer steel M2c Rotors just to keep the BMW only theme going.

I like pushing the stock stuff and comparing it to others who have modded. I know there are better times to be had with upgrades, but then again upgrades are only made reality with a baseline.
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      06-22-2020, 06:53 AM   #6
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Quote:
Originally Posted by JLS_397K View Post
I hope to see how this pans out. I will try to get a couple of track days (west coast) myself in my GTS but i think this will be far and few between. I going to leave mine rather stock. Other than dedicated rims tires(apex), ill probably switch to newer steel M2c Rotors just to keep the BMW only theme going.

I like pushing the stock stuff and comparing it to others who have modded. I know there are better times to be had with upgrades, but then again upgrades are only made reality with a baseline.
I had no intention to mod. The problem is that pushing the stock stuff yields the results explained above.

I'm after durability more than speed. Aside from lap times, baseline has already been improved because tires lasted the day and I was solidly in the seat.

For what you describe and assuming casual track time, might be that no changes are necessary. If I backed off 5 seconds/lap would probably still be on original Cup 2 and not showing any signs of rotor wear. But the car is too fun when pushed...
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      06-22-2020, 11:36 AM   #7
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Quote:
Originally Posted by FormulaMMM View Post
I had no intention to mod. The problem is that pushing the stock stuff yields the results explained above.

I'm after durability more than speed. Aside from lap times, baseline has already been improved because tires lasted the day and I was solidly in the seat.

For what you describe and assuming casual track time, might be that no changes are necessary. If I backed off 5 seconds/lap would probably still be on original Cup 2 and not showing any signs of rotor wear. But the car is too fun when pushed...
HAHA, I remember I ran into someone else at Bimmerfest who said the same thing "I had no intention to mod." Its funny that we have BMWs top dog(F82 gen) for track enthusiast and yet we want more because there is more to be had.

It would be great if BMW had just given more M3/M4/GTS with components from GT4 upon request. YES yes, I know you can buy aftermarket/replica components from GT4, im just saying...Something like the Apollo IE where they give you set of track brakes/rotors and 18 inch rims as an option. Pipe Dreams...

You are correct, it would be casual, however when I am at the track... I am out to best myself as much as I can. If those lap times ultimately start comparing to fellow track enthusiast, that will bring more excitement to chat rooms and garage talk.
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      07-02-2020, 08:19 PM   #8
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Time for a diet. Weights are approximate, but pretty darn accurate, I think.

- Driver & passenger Weathertech mats: -2.8 lbs.
- Trunk carpet piece over water tank: -5.2 lbs.
- U.S. spec GTS passenger seat: -52.6 lbs. (M3 drivers have no friends)

Updated driver's side Profi XL setup & harnesses = 37.4 lbs. (-15.2 lbs.)

~75 lbs. down.

Will share race seat setup details soon. Fingers crossed, believe I finally found a combination of components that work and I'm content with.

Gained more orange cage visibility and more racecar status.

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      07-03-2020, 11:22 AM   #9
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Fixed race seat

Pretty sure I figured the race seat setup. Only took like 2 yrs. Probably still room for improvement, but a step forward for sure.



Mod at your own risk, I'm not a safety engineer, consult a professional, and so on.

But some of this might keep you off of suicide watch if you decide to go it alone, or at least help you screen the components you want to try to work with.

Setup involves:

VAC floor mounts
VAC anti-sub bracket
VAC seat belt adapter
Brey Krause direct to floor seat mounts
G-Force 6 pt
Profi XL



Key items this combination solves vs alternatives:

- Lap belt clip ins are integrated into the BK mounts, thank you baby Jesus.



Bolting the usual lap belt mounting brackets on the underside of the floor mounts creates unevenness against the floor. At least if you're keeping your carpets in place, and maybe even if not, the floor mounts are "arched" when torqued down. Unavoidable, as far as I can tell.

The arch is substantial enough that when I originally tried to install a slider, the bolt holes wouldn't align. And even if they did align, I would have had to torque the slider rails so that they bent to follow the arch of the floor mounts, which wouldn't have worked. Installing a few washers under the mounts (elevating them) permitted me to bolt in the slider, and freed up a little bit of slider movement, but not much.

The low key BK lap belt clip in also permits the seat being mounted as far as possible inward/toward the tunnel, which is how you're going to get square to the wheel. You need to be working with the set of floor mount bolt holes furthest inward/toward the tunnel. If you're not all the way over toward the tunnel, you'll be notably off center (left). With the previous setup, I was off enough that I'd feel the seat edge digging into the back of my right shoulder when turning right, for example.



With the mounting brackets installed on the underside of the floor mounts and protruding outward, they also run into the floor of the car as it angles up on both sides. The brackets limit how close you can get to the tunnel, and require some bending to follow the car floor.

So, anyways, the lap belt clip ins integrated into the side mounts seems like a little thing, but it's a godsend. They should all be like this…

- Stacking the VAC floor mounts and BK seat mounts creates enough elevation for me (6'2").

The BK direct to floor seat mount slots -- at least the set I got -- didn't align with both the front and back floor bolt holes, but this setup would have been too low anyways. You'd probably have to be 6'5" - 6'6" for the direct to floor to work in the F8X.

The numerous VAC floor mount bolt holes and BK mount slots allow for a few different positions where there's alignment. The nearly perfect position for me allowed enough room for the VAC anti-sub to be bolted in at the back of the floor mounts.

The compromises of this setup:

- No seat movement.

- The 3 pt situation is a true safety compromise. I didn't transfer the stock system over, but the BK mounts are designed to integrate the stock buckle. However, if you get the seat into the proper position, as close as possible to the tunnel, I'm not sure you'd be able to snake it up anyways. The 6 pt is the priority for me.



I'm not going to get into all of the details of my trials and errors, parts returns, exchanges, and throwaways, and not intending to sound rude, but seat component vendors need to do more hands-on development work with the F8X.

imo the ideal 6 pt component solution would involve:

- A base that centers the seat (tight to tunnel) with anti-sub bracket integrated.
- Slider (optional).
- Side mounts with substantial forward/backward and vertical adjustment range, lap belt clip in integration, and 3 pt buckle mounting point. (BK address 3/4 of these needs, but not enough vertical position options for F8X.)
- Passable 3 pt solution. I don't know, but even the old style floppy 3 pt buckle that could be snaked through the seat opening would seemingly be better than what I have.
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      07-03-2020, 01:56 PM   #10
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I still wake up at night with cold sweats from the horror of installing seats for the first time. Macht Schnell hardware + Recaro hardware.
What a pile of shit. I still have all that crap in the basement, I haven't been able to bring myself to sell it.

Eventually I stumbled onto BK. Finally! Stuff that actually works! I retained oem sliders which are infinitely better than Recaro sliders and have 3 points + 6 points the way you have it.
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      07-03-2020, 03:33 PM   #11
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Quote:
Originally Posted by SYT_Shadow View Post
Eventually I stumbled onto BK. Finally! Stuff that actually works! I retained oem sliders which are infinitely better than Recaro sliders and have 3 points + 6 points the way you have it.
lol, night terrors and cold sweats. Thought I was the only one to have been through it.

Believe you mentioned BK in another thread, thanks. Looked up their mounts, saw the lap belt clip in points and nearly fell out of my damn chair. Immediately realized it's what was missing as I struggled to make other components work together for countless hours.

Should have mentioned they have the OE slider option. Can you squeeze in the 3 pt buckle in close to the proper position or have you run it like I did?
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      07-03-2020, 03:50 PM   #12
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Quote:
Originally Posted by FormulaMMM View Post
lol, night terrors and cold sweats. Thought I was the only one to have been through it.

Believe you mentioned BK in another thread, thanks. Looked up their mounts, saw the lap belt clip in points and nearly fell out of my damn chair. Immediately realized it's what was missing as I struggled to make other components work together for countless hours.

Should have mentioned they have the OE slider option. Can you squeeze in the 3 pt buckle in close to the proper position or have you run it like I did?
I think we don't hear about seat mounting so often because shops usually do it. I guess shops who have done these installs know what works and what doesn't.

Unfortunately my 3pt is set up the same as yours. If the buckle were a little longer I could route it properly.
I guess the options are these:
-Run the 3pt out of the way like we have it
-Run the flabby 3pt and then run it properly, but then you lose the pyrotechnic setup
-Run a seat that accepts the oem 3pt, like the Cobra Nogaro

The thing is I run the Sparco Ergo which has removable halos. For me it's the perfect seat for a mixed duty car even if the 3pt is routed incorrectly.
I don't have a cage or a half cage in my car but won't compromise with the halo seat.
Apparently the Cobra Nogaro is made in a way that accepts the regular
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      07-03-2020, 03:58 PM   #13
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were was this post two weeks ago.

I am in the middle of putting this together for my GTS as well. Number one issue is I am 6'5''.

Running Profi XL. Mounted on Recaro pole position side brackets. I was told using these side brackets help achieve centering the Profi best to the steering wheel. Waiting for Mach Schnell floor mounts and sub mount to arrive with the the universal bracket for 6pt.

My biggest concern is not being low enough.

What was the main issue you with macht Schnell?

Also what did you guys use for coding the airbag light?

Appreciate any info. I was surprised how little most shop knew in regards to setting up the F8x with seats.
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      07-03-2020, 04:09 PM   #14
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Quote:
Originally Posted by littlebully View Post
were was this post two weeks ago.

I am in the middle of putting this together for my GTS as well. Number one issue is I am 6'5''.

Running Profi XL. Mounted on Recaro pole position side brackets. I was told using these side brackets help achieve centering the Profi best to the steering wheel. Waiting for Mach Schnell floor mounts and sub mount to arrive with the the universal bracket for 6pt.

My biggest concern is not being low enough.

What was the main issue you with macht Schnell?

Also what did you guys use for coding the airbag light?

Appreciate any info. I was surprised how little most shop knew in regards to setting up the F8x with seats.
I would return what you received and get the BK stuff

I coded the lights myself. You are welcome to come see the car, we aren't that far
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      07-03-2020, 04:40 PM   #15
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Quote:
Originally Posted by littlebully View Post
were was this post two weeks ago.

I am in the middle of putting this together for my GTS as well. Number one issue is I am 6'5''.

Running Profi XL. Mounted on Recaro pole position side brackets. I was told using these side brackets help achieve centering the Profi best to the steering wheel. Waiting for Mach Schnell floor mounts and sub mount to arrive with the the universal bracket for 6pt.

My biggest concern is not being low enough.

What was the main issue you with macht Schnell?

Also what did you guys use for coding the airbag light?

Appreciate any info. I was surprised how little most shop knew in regards to setting up the F8x with seats.
Is your intention to run 6 pt? If yes --

You're probably tall enough to run the Brey Krause direct to floor mounts, without the floor mounts underneath as I installed. Then you'd install their anti-sub bracket along with. Without a doubt it's the solution that will get you lowest in the car.

https://www.bkauto.com/R_9283_for_La...s_p/r-9283.htm

https://www.bkauto.com/R_9258_Sub_St...m_p/r-9258.htm

But like I said, the BK direct to floor mounts that I received didn't quite align with the bolt holes. If I installed the rear bolt, the edge of the slot up front would impede the bolt. To resolve, maybe you could machine out a small chunk and be ok. I didn't get that far because I concluded that I was too low without the floor mounts anyways.

Here was the issue, just that far off.



The side mounts don't really determine centering... it's your ability to get as close as possible to the tunnel. The BK mounts allow this better than any other solution I've come across for the reasons stated in the post above. And the side mounts you have don't have clips for the lap belts.

Coding -- I just finished a 2nd session with MikeBenvo BPMSport. He addresses all warning lights. Threw in cancellation of the legal splash screen out of the goodness of his heart. Highly recommend.

But can't beat SYT_Shadow's offer.

Better a shop admit they're inexperienced than act like every issue you run into is a first.
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      07-03-2020, 05:39 PM   #16
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Direct to floor mounts are a pain. I've tried everything in the book and can't get the seat centered so I decided to make my own. I'm no engineer but I read through the FIA regulations cover to cover and think I may have come up with something (that I feel confident in). It will have provisions for a bolt on sub strap, detachable eye bolts for the lap belts (6 point) as well as a provision for the stock three point receptacle. I had an even more difficult time making my seats work because the 2700g has a bespoke side mount so the BK stuff won't work. I think the real solution to this would have been for BMW put the correct seats in the car for the US market to begin with. Nonsense.

I had my first design 3D printer to verify fitment and need one revision. There's slightly too much interference with the trans tunnel. It's compressible enough to force it to fit but if you're gonna go from scratch may as well do it right.
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      07-03-2020, 06:02 PM   #17
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Perfect, I'll be copying your setup FormulaMMM. Did a Thursday evening session at my home track, logged 160 miles and my right knee and left hip are sore from bracing myself in the seat. I've felt less beat-up after a 3-hour enduro stint, maybe I've gotten soft.
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      07-03-2020, 06:19 PM   #18
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As a note, the power cut at 1/8 of a tank is not due to the ECU doing anything, it's due to fuel starvation. With the tank that low, any g forces (braking, acceleration, turns, etc...) can cause the fuel pickup to not get a full pull of what's left in the tank, resulting in a heavily lean mixture, which is obviously not good for the car. The lean mixture results in knocking, and the ECU cuts timing.

I try never to get my M below 1/2 of a tank on track days, and NEVER below 1/4 of a tank. Not a GTS, but same principle.
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      07-03-2020, 06:37 PM   #19
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Quote:
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Perfect, I'll be copying your setup FormulaMMM. Did a Thursday evening session at my home track, logged 160 miles and my right knee and left hip are sore from bracing myself in the seat. I've felt less beat-up after a 3-hour enduro stint, maybe I've gotten soft.
Been there! Why I was willing to go through so much crap to get a race seat in there. Please reach out if I can be of help as you work through. To repeat, one potential problem with the setup I've outlined is that you determine ideal seat position but then can't find a set of floor mount bolt holes that align front and back with the BK mount slots.

Just went for a drive, I'm still pretty low using the top slot of the BK mount. That's a good thing, will get used to it, but if I were a couple inches shorter believe I'd be too low for good visibility.
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      07-03-2020, 06:39 PM   #20
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Originally Posted by Dave 90TT View Post
As a note, the power cut at 1/8 of a tank is not due to the ECU doing anything, it's due to fuel starvation. With the tank that low, any g forces (braking, acceleration, turns, etc...) can cause the fuel pickup to not get a full pull of what's left in the tank, resulting in a heavily lean mixture, which is obviously not good for the car. The lean mixture results in knocking, and the ECU cuts timing.

I try never to get my M below 1/2 of a tank on track days, and NEVER below 1/4 of a tank. Not a GTS, but same principle.
Sound advice, but this was definitely an ECU intervention. 18 mile range indicated, gong, and power cut simultaneous. Was 1/2 way down a straight.

I've been ~1/8 tank before on road and it's given full power. The calculated/indicated range was the difference here.
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      07-03-2020, 06:54 PM   #21
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Originally Posted by Lienrocs View Post
Direct to floor mounts are a pain. I've tried everything in the book and can't get the seat centered so I decided to make my own. I'm no engineer but I read through the FIA regulations cover to cover and think I may have come up with something (that I feel confident in). It will have provisions for a bolt on sub strap, detachable eye bolts for the lap belts (6 point) as well as a provision for the stock three point receptacle. I had an even more difficult time making my seats work because the 2700g has a bespoke side mount so the BK stuff won't work. I think the real solution to this would have been for BMW put the correct seats in the car for the US market to begin with. Nonsense.

I had my first design 3D printer to verify fitment and need one revision. There's slightly too much interference with the trans tunnel. It's compressible enough to force it to fit but if you're gonna go from scratch may as well do it right.
That's next level! Please share the finished product when you get there.

Agreed.. buckets would have been nice. But as someone pointed out elsewhere, those are standard Pole Positions in dimensions, so the shoulder harness positioning wouldn't be right for taller guys anyways.

With the setup above I can slide the BK mount slots maximum right (facing the front of the car), so even more inward of the OE floor bolt holes and innermost row of floor mount bolt holes. The side mount slot movement doesn't buy a whole lot more, but feel pretty centered. Seat would be bumping the tunnel if I moved almost any further inward.
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      07-03-2020, 07:26 PM   #22
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Quote:
Originally Posted by Dave 90TT View Post
As a note, the power cut at 1/8 of a tank is not due to the ECU doing anything, it's due to fuel starvation. With the tank that low, any g forces (braking, acceleration, turns, etc...) can cause the fuel pickup to not get a full pull of what's left in the tank, resulting in a heavily lean mixture, which is obviously not good for the car. The lean mixture results in knocking, and the ECU cuts timing.

I try never to get my M below 1/2 of a tank on track days, and NEVER below 1/4 of a tank. Not a GTS, but same principle.
I thought it fuel starved at 1/3 of a tank but actually even a hair lower than 1/2 and it happens.

Keep in mind the fuel pump will die if this happens enough and it's expensive as hell
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