Hello all, With the 17” tyres becoming scarce, I am considering upgrading my wheels to 19”. I have come across the BBS Unlimited range of wheels which offers a range of adapters and spacers to achieve fitment on some of the more difficult configurations. The local agent contacted BBS and had the following response: “Unfortunately, we have very little data available on what is feasible for the Ferrari, but we would offer the following combination. On the front axle, 9.0x19 ET45 concavity 1 The rim protrudes 11 mm further than the standard rim. On the rear axle: 10.5x19 ET18.5 concavity 3 The rim protrudes 13 mm further than the standard rim.” Would a protrusion of 11mm at the front and 13mm at the rear be a concern? Some suppliers have also asked about the brake caliper clearance. Would anyone have measurements that I could pass on to the supplier to ensure we build the wheels correctly? I appreciate any guidance from the team on the forum. Kind regards, Rian
Maybe not helpful, then forgive me. But a 2" bigger wheel with such an open design will make our discs very visible, and the 19" will make the discs look small IMO. I've had the same thoughts myself, for now I stay at 17", if upgrading in the future I'll try to only go to 18" if tires available Just an opinion
The wheel wells on the 456 GT can easily take much larger wheels, including those you list. Novitec NF2s fit and those are 9X19 F and 12.5X19 R. Here are the specs on the original 456 wheels and the NF2s to give you a starting point. Make a drawing with the OEM wheels offsets and the offsets your new wheels will have to get a feel for how they will fit. 456 GT/456M Five Spoke 17”, 5 X 108 mm Front 8.5J X 17 ET 50 mm, Rear 10J X 17 ET 24.6mm Novitec NF2 (Not OEM) Five Spoke, 19”, 5 X 108 mm Front 9J X 19 ET 28 mm, 33.6 lbs, Rear 12.5J X 19 ET 51 mm, 39.6lbs Image Unavailable, Please Login
The size you spec'ed will be fine if a little conservative. IMHO, the ideal size for the 456 (all variants) is as follows: 9in ET40 Front 11 vs 11.5in ET20-25 The front: If you go lower offsets, they tend to stick out hotwheels style too much (in my opinion). Lookup what most 456 with Hamann or NF2 wheels look like for an example. The rear: 10.5ET19 is the spec I am running right now on my car (OEM 10.5ET34 rear Modular wheels with 15mm Hill spacers = net 19mm rear offset for the 10.5 factory rear wheel). I have 11.5ET21 wheels that I am (trying) to have built (hopefully in the next few weeks). Here is what 9ET40 and 10.5ET19 look like on my 456m with standard brakes with factory FHP/Euro ride height specs adapted from Euro 550 FHP specs (note I have also designed an OEM+ brake kit for the car but it’s later after I first finish the wheels given my rears are still attempting to be built). Note if you would be happy with the rears, keep as is on your current build but I would ask about options for slightly lower front offsets between ET40 and 45 if they can offer. Your bolts would be M14x1.5 but be warned the 456 is very sensitive to overall bolt length. It is very easy to hub them in the back if they are even a hair too long (3mm). Your actual bolt length will be a function of the wheel+adapter/spacer they use obviously so I can't tell you what you need there as I dont know the specifications BBS uses today / after there what 2nd? bankruptcy. The factory modulars were also BBS contract but built to cost and clearances not to quality but hey I fixed that....
I should note I have spent many hours calculating, testing, re-calculating, retesting to come up with the above. I re-barreled factory modular wheels and given the extreme cost and scarcity of OEM modular wheels centers, complexity of sourcing correct filament lips, the correct titanium assembly bolts, etc, I did NOT want to have spent over 5 figures and countless hours to only have un-useable wheels. Also be VERY careful with wheel+tire weight. The 456 rear suspension given its SLS system is extremely fragile and can (WILL) fail prematurely if you mount overly heavy wheels (given their effect on shock rebound>compression). "Fortunately" the factory 17x10 ET24.6 rear wheels are HEAVY at around 29.5-30lb so most aftermarket wheels are fine.
Terry and Omar, thanks for the explanation and pics. Michael, thanks for raising the point on the brake disk diameter. The potential of a brake upgrade is also at the back of my mind.
Brake upgrades for the 456 can range from reasonable to comically expensive. I’m going to include all the possibilities I just haven’t actually had a chance to sit down and write it. One thing that I have never been able to independently confirm is whether you can do a 456GT>456M front brake upgrade by simply swapping the calipers and rotors or if it requires swapping the hub/knuckles as well. if it is just a caliper and rotor swap, that would be the best cost per upgrade, particularly if you pair it with FHP or similar level brake pads (Pagid RS 4-4)
