Merry Christmas and Happy New Year everyone! Apologies for so few updates recently. We have been very busy moving YMS into our new 6000 sq ft facility in Whittier CA.
We have been contemplating building the car into a street class time attack car, a track day car, or a Pikes Peak car. We were at the SEMA and PRI show pulling together some partners to get a better feel for which direction we should take the car. It looks like we are going to end up doing a little bit of everything!
Our ex Formula 1 engineer Ricardo came over from France for a week to get his hands on the car and we planned the build quite extensively. The focal point in the next months will be stripping weight and optimizing the suspension. We have been in contact with BMW Motorsport to get an understanding of how the suspension in the M4 articulates. In order to engineer the car at a high level, we need the suspension coordinates which are extremely difficult to measure ourselves due to the M4's asymmetrical multi link suspension. Once we have the coordinates, we'll have a better idea of if we need to redesign the geometry.
We spoke with Dallara, the biggest formula car manufacture in the world about making a carbon body and aerodynamic parts for the BMW M4. As you can imagine, having Dallara make anything is not cheap! This would depend on if we could do a small production run of track day special M4s. Please refer to this post:
https://f80.bimmerpost.com/forums/sh....php?t=1681460.
The car will be getting stripped down in early January so we can weld in a roll cage and cut out pieces of the frame that we don't need. We originally planned to do our own twist test but according to BMW M, the M4 takes 40,000NM per degree of twist. That is incredibly stiff for a car without a roll cage. To put it into perspective, a Formula 1 Monocoque takes about 36,000NM per degree of twist. When Ricardo was technical director at Nissan from 1996 to 2012, they found that the optimal stiffness of a racecar is 40,000NM per degree of twist. If you look closely at modern OEM racecars including the M4GT4, there are minimal gussets between the frame and the roll cage because the cars are already massively stiff. All of this means the M4 can have sections of the frame removed after we put in the roll cage.
One of our customers commissioned us to build his A90 Supra into a caged track day car so will be caging both cars at the same time.
Please let me know if you guys are interested in more in depth technical detail. We are creating a youtube channel to document the M4 and our customer builds. The first video will be linked here as soon as its up. Give us a follow on Instagram @ymotorsport to follow the build more closely.