Is it a new chassis or the same chassis built for the F12?
I presume the chassis of the 812 is basically the same of the F12 Berlinetta. What's new at this level is the second generation of Virtual Short Wheelbase, an evolution of the first-generation system used on the F12tdf, that sharpens the car’s handling to give quicker steering response times.
Right. If you mean the basic structure of the car, then it appears so. If you mean the exact suspension components, then it seems it is improved, plus the addition of the rear steer, and the change to electric power steering. From the seat of the pants, the car feels like it could almost be a different (newer) platform.
I take chassis to mean same configuration of structural elements with similar geometries from which the rest of the elements are attached. From F12 to F12tdf the chassis elements are depicted as follows: Image Unavailable, Please Login They are clearly the same basic chassis. The specific pieces may be slightly altered to support the desired result but it would be fair to say they share the same chassis. The diagrams for the 812s have not been made available for the sites I check so no direct comparison is documented in public. However, it was said the 812s is based on the F12tdf. If so, then expect some modifications as with prior but not a new chassis in the sense that it is re-visioned to support a new concept chassis. Checking the actual parts diagrams and cross-checking the part numbers across models can tell you a lot about what is the same and what is just carryover. A lot of myths can be proven or disproven by facts.
That's how the F12 Berlinetta chassis looks. Image Unavailable, Please Login Image Unavailable, Please Login
Yes as well as the F12tdf, F60, TRS, SP America, Singapore 50th Anniversary Edition, SP 275 RW Competizione, SP3JC, 812s, unknown one-offs and likely a lot of it on Monza SP1 and Monza SP2 and likely other Iconas. Not sure if I left any well known others out. A very successful design for Ferrari.
Well the front is a little similar in shape. This was a photo of my car [ LOL] but its a LHD and mine is RHD Image Unavailable, Please Login
Which in particular? Are you referring to the roof, A+B pillars, etc. ? If so, the shapes between the F12Berlinetta and F12tdf are nearly identical with 7 of the 11 pieces having exact interchangeable part numbers (source Eurospares): Image Unavailable, Please Login
Its all of it. I would not advise you drive your F12 without those parts The OP asked if the 812 and F12 are the same chassis. I think it depends on how you look at it. I would say its an improved F12 chassis.
The slightly wider rubber at the front also helps. Didn't realize that the 812S had a larger footprint up front (275/35 vs 255/35) until I was shopping for tires recently and checked the 812 specs vs F12. Rears are the same but undoubtedly with a wider track, no?
As published on Ferrari.com: front track: F12Berlinetta: 1,665 mm, 65.6in F12tdf: 1673mm, 65.9in 812s: 1,672mm, 65.8in rear track F12Berlinetta: 1,618mm, 63.7in F12tdf: 1,648mm, 63.7in 812s: 1,645mm, 64.8in tire and rims same specs for F12tdf and 812s: Front 275/35 ZR20; 10” J x 20” Rear 315/35 ZR20; 11.5” J x 20” tire and rims for F12Berlinetta: Front 255/35 ZR 20 9.5J Rear 315/35 ZR 20 11.5J I note that some of the conversions above from the Ferrari website are not correct between inches and millimeters so not sure which is correct. Also,the 812 inches values were calculated from the given millimeters as inches were not given. The front upper and lower control arms have different part numbers for F12Berlinetta and F12tdf which could drive track. Factory stated that front track and resulting tuning of RWS was a laborious calibration for F12tdf. Wider tires gripped more but rear end performance was unacceptable (they actually first tried to put the read wheels on the front and had big issues). Minor changes have large impacts in controllability. It is generally believed that F12tdf and 812s share the same RWS but with less edgy calibration which made F12tdf more challenging to drive on the limit and made easier on the 812s. 812s control arms part numbers not posted yet to the general public. Note that control arm length and wheel offset are part of track so using same compatible tire sizes may not result in same exact track between vehicles.