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Mission8: Trials and tribulations of creating BMW's latest GTE

Mission8: Trials and tribulations of racing BMW's latest GTE

On September 2017 the BMW M8GTE made its first public appearance at the Frankfurt Autoshow. 
Set to compete in both the  2018 FIA World Endurance Championship and the IMSA WeatherTech SportsCar Championship,
it also marked BMW's return to Le Mans with its first factory-backed car since 2011. 

[Image: 2017-pres-frankfurt.jpg]
Talking shop
Press releases were full of the usual corporate shop talk, how the new M8 would be sporting a 4.0-liter twin-turbo V8,
make about 500 horsepower and would incorporated BMW's latest cutting edge technology, aerodynamics, laser lights
...bla, bla, bla....

Clearly the Munich brand was grabbing the opportunity to use the GTE as a marketing tool for its M8 coupe road car.
The street legal version of the M8 GTE not due to make its first appearance until may 2018.

I could not have cared less, chances are I'll never be able to own a M8, let alone race one in the flesh. 
The moment I saw the first images of the GTE, I stopped reading...cause all I could think of was:
"How was I going to get my hands on that car.... and race it at Le Mans...1/32nd"

[Image: M8GTE-wip01.png]

Time Flies when you're having fun
Since then two years have past, time sure flies when your having fun. A lot has happened in between, the M8 has won the Daytona 24hrs...
...and has been canned in the WEC. I waited almost a year for one of the major manufacturers to do this car...never happened.
So exactly one year ago I decided not to wait any longer, and started my own mission8.

In this topic I will post the trails and tribulations I've come through on my Mission8. As I write this the project is already starting its second year...
So before I start posting...I already have a shitload of backlogged posts Bigsmile

From a unique scratch build  one a limited production kit
But before I turn the clock back to 2018, here's an image of how far the project has advanced so far.
I took this image a week ago, it shows the 3D printed body that will be used as a master for the GRP laminated body...
...or actually bodies.  
Because as the initial Mission Goal is now within reach, I have decided to extend the mission objective.
In the last 6 month I've been working closely with SV Workz on other projects . As a result of this close cooperation we've decided to do a limited edition run of mission8 kits. 
Meaning that after I've run the car at the 1/32nd 2020 Le Mans 24hrs... you could race this car too.

To be continued:
[Image: mission8-SV-presentation01.png]

With kind regards

Attached Files Thumbnail(s)
[+] 5 members Like Tamar's post

That looks outstanding Tamar.... look forward with interest to the build

Only sad note is BMW have pulled out already from LM racing.....  no matter at all a beautiful car is a beautiful car Rofl

LOL Anthony, spoiler alert, you are ahead of my posts  Bigsmile

BMW M8 GTE Suckerpunched by the BOP?
As Anthony mentioned: On May 22nd 2019 The German manufacturer announced that its works program with the BMW M8 GTE would not be continued after the 2018-19 WEC ‘Super Season’, while its IMSA WeatherTech SportsCar Championship project with Team RLL would carry on. 
As such the 87th edition of the 24hrs, where BMW celebrated the 20th anniversary of its 1999 overall (BMW V12 LMR) and the 80th anniversary of its first class win (BMW 328) would also be the last time for the Grande Coupe at La Sarthe.

As both the V12 LMR and the 328 were given a celebration parade lap before the start of the race it was pretty pretty obvious to BMW that there would be little chance of such celebration after the race. 

Many fingers pointed at the B.o.P (Balance of Performance) as the main party pooper, and yes BMW had been complaining about the B.o.P (or lack off) ever since the car's debut in the Daytona 24hrs. But was that truly justified?

Balance of Polictics?
Love it or hate it, a B.o.P has been used by most race organizers for GT classes for some time now. Its main purpose is to create a level playing field amongst the very differently configured road based cars the race GT's are derived from. Front engined, mid engined, rear engined, atmospheric or turbo charged, you name it, the GT class has it. And in most cases (like in GT3) it works. But for the classes the M8 was intended to was a bit of a different story.
Both the IMSA GT LM and the FIA WEC GTE class can be considered as the top tier classes in GT racing. Although they're still based on road going models, there are greater liberties for a manufacturer to exploit to tune that original model into a near purpose build race car. And that's where politics enter the game.
Because long before a racing GT has turned a wheel, major manufacturers will have been in "constructive talks" with the sanctioning organizations, trying to optimize the specs under which their car will be allowed to compete. Reduce the negatives and improve on the positive sides of the road based model so to speak
One of the negatives BMW wanted to reduce..literally... was the size of their car.
There are provisions in the rules for deviations to the base model (allowing Porsche  to build its mid engined 911 GTE) and BMW did request to shorten the M8 by 10cm. However such requests must to be approved by all other manufactures in the Class. Guess what their answer was....

As apparent by the meme's hitting social media for the 2018 LM 24hrs... the BMW M8GTE was always going to be a big car. 

to be continued

With kind regards
[+] 1 member Likes Tamar's post

What happened Tamar? Interesting read, cut off mid flow. .............
Did the cat knock your beer over?  Beer Tappingfoot 

 Or something else.... we deserve to know.

Steve A

Just keeping you guys eager to keep reading ;)

No just kidding, was writing a more complete post with the whole story, but as I needed to change, remove, replace an attachment I hit the wrong button and the draft got posted instead. So I edited it and finished the post to where it would make sense to split.

As I wrote

to be continued ;)

with kind regards
Big Grin 

Good evening Slotfriends.
Today we're 4 weeks away from travelling to Leamington Spa for the 9th Edition of the Disca Le Mans 24hrs....and it has been more than six months since my last "confession". One which I broke off quite abruptly by the way. I still owe you the rest of that story  Time
Time for an update on my 
Mission8 also know to insiders as "Mission wait"

Because for many months after posting the first publication photo's of the 3D printed I managed to do was cut and test fit one master for the right hand headlight lens and one for 
right hand the tail light lens...not much to write a progress report on.

[Image: SV8GTE-wip02.png]

M8 waiting game
At first the M8 was intended to make its debut at the DiSCA finals in Barcelona on Nov 4th, remember I posted those publication shots in August plenty of time right?.
Well I got a bit more involved into the organizational work for that final than was provisioned enough time to finish the BMW....raced the Ford GTE...again...
...and plenty of time till the next event in Januari right?
So November flew by, but by half December Stefan Nalbach (Prospeed) send me the first renders of the Hybrid M8/M6 3d design.
The M8 Mk1 chassis was a hybrid version that allowed us to run and test the M8 Chassis under the M6 GTE we raced last year at Suzuka.
As you can see its got the M8 diffuser attached to the motorpod . The same way as first used on the Ford GT.
[Image: SV8GTE-wip03_chassisMk1.png]

Got the chassis printed in time for the dec 15 test we had @ the Suzuka track, December is always busy work wise but with a last minute push we managed to get the Hybrid M6/M8 chassis assembled and up and running under the "old" GRP M6 body.
I had also modified the original M6 chassis mounting the diffuser to the NSR SW pod "Ford Style"
The new Prospeed M6/M8 chassis is similar to the one Prospeed used for their C7R corvette they raced at LM 2019.
It has a Prospeed shortcan motorpod with a  10˚AW/SW configuration and 1,0 mm offset.  Attached to the rear the "now correctly sized" M8 rear diffuser.
Had to shave 0,1 mm off the bottom of the strakes as they touched the track on the first roll out  (later I found out that I had not tightened the diffuser screws completely)
Must interesting was how the Hybrid chassis with its narrower and more forward position of the side suspension compared the old NSR podded M6 chassis. 
[Image: SV8GTE-wip04_chassisMk1.jpeg]
The first test went very well, the new chassis was still a bit slower, but showed promise. I'd figured that we needed a bigger offset pod to get it on par with the Ford, had a quick chat with Stefan Nalbach who immidiately made one and had it printed asap by Shapeways. It arrived just in time to be assembled and run in the last test sunday before the Suzuka 6hrs on Jan 20...
But there things took a bit of a downfall.

With the new Motorpod the M6 ran well, nice and smooth...but when we checked the times was 3-4ths slower than the Ford.?
And when we start pushing to match the Ford's times the BMW became very unpredictable ?
We switch back to the "old" prototype M6 chassis..and same thing. 3-4ths slower than the Ford and unpredictable when pushed hard.
We tried several different set-up changes to make the M6/M8 behave...but it would'nt...and then we ran out of time.

With still a ton of organisation work to do in the week till the race and with no gauarantee we would manage to solve the problem during saturday's free practice.
...we decided to not run the M6/M8 and race the Ford instead....again.

A good call as it turned out the weekend after. First of all with the more stable Ford even though I was waisted as usual we did manage to take 2nd place overall and win our GT class.
But by just one lap difference from the second placed GT car: the Prospeed Corvette C7R. 

By now it was Jan 31st which was the cut off day, last day, according to DiSCA rules, to  pay the remaining enry fee and make changes to your car choice for the LM 24hr race. 
And although I had an idea on how to fix the problem with the BMW chassis....we decided to go for the plan B and switch back to the Ford GT. Better safe than sorry.

To be continued

With kind regards
[+] 1 member Likes Tamar's post

Dinnertime meant I had to cut off writing, also made for a nice cliff hanger [Image: wink.png]
Because I would not be posting here if there wasn't more to the story than just another race cancellation for the M8

Weight off my shoulders
Because with making that difficult call to switch to Ford for the DiSCA was like a heavy weight was lifted of my shoulders.
And as it happened, I also had some free time on my hands in the past weeks.
Time I did manage to spend on the M8, finishing the master casting the silicone mould and laminating the first body.. that last weekend we had our first roll out @ Suzuka.
Finally after a year an a half, there is a 1/32nd M8 GTE.

[Image: SV8GTE-wip05_rollout.png]
To be continued

With kind regards
[+] 1 member Likes Tamar's post

Hello slot friends. As you may have noticed the posts in this thread are jumping up and down the sequential timeline of the GTE build.
Its a bit like watching a TV series that starts near the end of the story and then tries to explain to you how they got there via lots of confusing Flashbacks [Image: wink.png]
So tonight's episode will grab your attention, its like an end of season cliffhanger, one that ends with a Big Bang  [Image: wink.png] 

A Penultimate Test
In the last episode we had the roll-out of the car in "naked" GRP. As a function test it performed well, we identified some handling problems and other issues like a bend chassis. (on which I will post later).
Spend most of my free time last week addressing them because this Sunday we had an other test day ion Best.  
Based on the results of Sunday's test we would make the final decision on if there might still be a chance to run the M8 at Le Mans.
So by Sunday afternoon I placed the M8 on the track, her body now dressed in a nice clean and white test livery, her chassis straightened and reinforced.

[Image: Pre_crash-test.png]
The SV8GTE all dressed up for her penultimate test.

I even managed to install the headlights properly, added the head and taillight lenses and mounted the flexible rubber Wing supports...cause I needed to know, would they stay on the car or come off during running...or crashing.
By the way, that's the Prospeed Corvette C7R flashing by in the background. They to were shaking down their Le Mans cars, so both teams could compare where they were at..with the competition [Image: wink.png]
First laps with the M8 showed that the car was now stable and predictable. No more bottomming out on the high parts of the track, initial lapttimes were in the low 12's.
Lennard did some consecutive runs with both the M8 and the Ford which showed that the track was a bit slower than last time.
The Ford also had problems getting below the 12 seconds but did manage an 11,96. Prospeed C7R's average times were in the mid 12's with a best of 12.09.

We then started to fine tune the set-up of the M8, mainly playing with the front pod screw and minor adjustments to the diffuser grubscrews.
Slowly, but steadilly the laptimes on the M8 went down. Lennard setting an 11.93 as best M8 lap of the day.

[Image: SV8GTE-test-run_0803.jpg]
The SV8GTE, Ford GT LM and the ProSpeed C7R  coming out of the 130R

With me and Steven being able to do low 12's and Lennard dipping into the 11's frequently we were pretty pleased with the M8...until it started to become a bit unstable again.
Upon inspection of the car we noticed that both front bodyscrewpost had sheered of in the body.
I sort of expected that this would/could happen as I had glued these into the body "rigidly" with cyanoacrylic glue (superglue) with a flexible glue on top.
The previous bodyposts I had glued completely with "flexible" Bison Tix or Bison Max repair.
What was unexpected was the apparent minor crash and force needed to break the bond of the Superglue, but on close inspection I noticed that the glue was still in place.
The post had seperated from the body by taking one layer of lamination with them.
[Image: SV8GTE-wip06_front-bodyposts_repaired.png]
The SV8GTE after I had reglued the most forward body screw posts with flexible glue (Bison Extreme repair) more on this in a later post.

Taking Stock, decision time.
With Steven and Lennard needing to leave, we took stock of the M8 situation and determined that we all would prefer to run the M8 instead of the Ford....
...That handling and speed wise they were alsmost on par and that with some more testing and development the M8 has the potential to become even better.
But given the uncertencies of the body posts, the fact that we would not have the first true 3DP race chassis from Shapeways before end of next week, which would require at least an other weekend of testing...
...and that we would still need to do the second body (lamination, paint and lights) ...with just 3 weekends till showtime...

We decided that it would be best to continue with the Ford and develop the M8 in the next race (most likely Rockingham this summer). this was supposed to be an M8 test, we did not leave it at that.

With the glue set enough to remove the body screws, we did another run with the M8 with the bodyscrews back in the original Carrera position (so glad I had left them in place in the body) to see if the car would be slower.
It was, by a tiny bit. Lennard now managing "just" a 11.96
End of the day, Lennard and Steven had left. I had one heavy last test to perform. I knew I had to do it, but kept postponing te inevitable...good thing I did.

I had noticed that the glue on the most frontal bodyposts had set...enough to re-mount the body on them and tighten the screws.
I then fiddled a bit more with the suspension travel, chassis float and increased the amount of pressure by which the body was leaning on the rear diffuser.
As I did this my laptimes with the M8 came down from the low 12.20's to low 12's and posted a best lap time of 11.96... and I'm usually at least 1 -2 tenths slower than Lennard.

So time for the last scene of this season finale

Crash test Dummies
When you're building a slot car with a laminated GRP body that you want to race in the DiSCA Le Mans 24hrs, the most tasking, demanding 1/32 digital endurance race in the world...
...How can you find out if its strong enough to survive a head on crash at full speed on the 16m long Mulsanne straight? 
Because these things can or beter will happen. do a crash this kind of knowledge...can only be acquired... the hard way!

[Image: SV8GTE-crashtest2.png]

Location: End of the Pit straight (6m long) 1/32nd Suzuka track, Src Eindhoven, Best, The Netherlands.
Test subject: 1/32nd SV8GTE GRP body 22 gr, total weight 76,2 gr
Crash test dummy: Our Scalex Nissan GTR "Safetycar", Injection moulded plastic body 35 gr, total weight 86gr

Here's the link to the you tube play list: SV8GTE Crash Testing
Note: Not for the fainthearted, no other slot cars besides the SV8GTE were hurt in these videos

to be continued.....

With kind regards
[+] 2 members Like Tamar's post

That video opens up a whole new world of 'slot car porn'!

Did you lift your finger off the throttle at all?

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