If you are reading this article you have likely already familiar with the legend that is the Volk Racing TE37. A truly classic design, the motorsport-inspired 6-spoke lightweight forged wheels have been put on everything from SuperGT racecars to overlanding trucks. It may not be the lightest wheel, but the strength of the TE37 is legendary and it is a halo wheel for enthusiasts.
A Brief History of the TE37
Founded in the early 1970s, RAYS and RAYS ENGINEERING are a high-end Japanese wheel manufacturer specializing in wheels for motorsport and street use. Forged wheel technology was once thought of as unobtainium, a method for making forumla racecar wheels that you would never be able to afford or fit on to your street vehicle. To this day, RAYS carries the slogan "The concept is racing". Through RAYS ENGINEERING's flagship Volk Racing line, forged wheel technology was brought to the masses. Volk Racing, uses the ultimate in high-tech forging technology that can be found on winning factory race teams in Japanese Super GT and the British Touring Car Championship all the way up to Formula One. Rays Engineering also manufactures wheels for in-house tuning arms such as Mazdaspeed, NISMO, RALLIART, STi, and TRD. At the same time, RAYS ENGINEERING produces exact specification performance wheels for street cars such as the Tesla Model 3. These are motorsport battle tested wheels that stand up to daily use that even the OEMs trust.
In 1996, Volk Racing sought out to develop a mass market performance-oriented wheel. The commission was to make a lightweight wheel that was as rigid and strong as possible, while still being able to accomodate large brake calipers. Their smallest specification, a 15x6", weighed in at 3.7kg (8.16lbs) and the Touring Evolution 37 was born.
While you may find lighter wheels in the same dimensions, as mentioned, that is not the only goal of the TE37. Rigidity is a material's resistance to bending. A more rigid wheel will theoretically transfer torque from the motor to the tires more efficiently. Strength is a material's resistance to breaking. Whether it is racetrack berms, accidental 4-off excursions, or that giant pothole at the end of your street, a strong wheel is a must.
All RAYS wheels start with Finite Element Analysis (FEA), which is a computerized method of analyzing structural stress. These FEA simulations allow engineers to determine where potential weak points in a design may occur before the wheel is ever made as a prototype. In order to meet their overall design goals, RAYS commissioned their own special sauce of 6061-T6 aluminum alloy that complements its in-house forging process and meets the specific rigidity and strength goals their engineers had in mind. The result is a wheel that has 20% higher tensile strength characteristics than your average aluminum wheel and happens to allow for better thermal conductivity to aid in brake cooling.
Design is nothing without execution. Forging is one of the oldest manufacturing methods known to man. Rather than pouring molten metal in to a mold as is the case with a cast wheel, forging involves shaping metal through temperature and compression. Think of the process a blacksmith would use to make a cast-iron frying pan compared to making a sword. Volk Racing uses a method known as mold-form-forging which creates the wheel's shape while the aluminum is being forged. As opposed to forged blanks having material machined away, mold-form-forging allows the metal's grain to be set as the wheel is taking shape.
While Volk Racing's forging techniques have evolved over the years, the basis of using their RM8000 rotary forging machine to apply 10,000 tons (!) of force has not. After the "negative" areas to the spoke are punched out of the wheel, it is heat-treated, machined for bolt holes and other details, and shot-peened for that extra bit of strength. The TE37 deserves every ounce of its Made in Japan label. Volk Racing are true craftspeople.
As an engineering company that takes pride in their work, RAYS Engineering has even developed their own JWL + R criteria to test their wheels which are even more stringent than the JWL standard which is Japan's official wheel testing standard and the worldwide de facto standard. RAYS believes that JWL is the minimum strength standard a wheel should achieve, and conducts its own practical strength tests. As part of their "JWL + R" specifications, RAYS puts their wheels through more stringent dynamic radial fatigue testing, drops a 2200lb weight (!) on the wheel, and performs spray testing on the outer coating to test for corrosion.
Though many replicas and imitations of the TE37 have been made, they cannot claim the vast majority of these design and production methods. This is what truly sets the "Touring Evolution 3.7" apart.
The Hack
This article focuses on mounting the Volk Racing TE37 on your Tesla Model 3. The TE37 has been around for over 20 years so finding one that fits the Model 3 seems like an easy feat. Just find a 5x114.3 with a reasonable center bore and offset and you are golden. Not so fast. Most Japanese Domestic Wheels (JDM) up until recently have been drilled for M12 studs and lug bolts. This means that the stud holes are 2mm too narrow in diameter to fit the Model 3's M14 studs.
This seemed a minor inconvenience to some. Simply drill out the bolt holes to some "OG" TE37s to 15mm while also drilling a 60 degree angle for the lugs. While this has been done by machine shops with success on the TE37 as well as other JDM wheels, this is not a method I would suggest. The FEA done on the original wheel design was done with M12 studs in mind and the lug pockets were designed for smaller hardware as well. Does this mean that the wheel instantly fail when you drill it? No. Does this mean you are guaranteed to weaken the material in the hub? Maybe. What is real is that this is a method that professional wheel repair shops do not recommend, but a means to getting the M12 wheel you want on to the Tesla Model 3.
The 19x9.5" +34 Ultra M-Spec
You better believe product marketers love having a huge screen with a web browser to show case their products during videos. In search of a solution rather than hoping and praying the machine shop or your friend with a drill press get the work on your expensive wheels done right? RAYS ENGINEERING to the rescue. Seeing the increase in demand for their beautiful wheels on the Tesla Model 3 they released the latest TE37 Ultra M-Spec in a 19x9.5" 5x114.3 +34 to cater specifically to the Tesla Model 3 platform.
The +34 features the Ultra designation designed for high-performance cars demanding 19"+ wheel diameters. It combines the TE37SL (Super Lap) machining of extra spoke material for lightweight and the rigid and stronger barrel construction of the TE37RT (Rigid Tune). It also features bead knurling like the TE37RT to prevent tire slip and a high-flow air valve. This specific wheel also carries the M-Spec designation which removes the machining ring around the rim. This is a sleeker look and once I personally prefer.
TE37s are available in 5 face profiles of varying concavity. The +34 offset is an easy plug and play offset and is forged with the TE37 Face 3 semi-concave face.
The 19x9.5" +28 Ultra M-Spec
Released to the public in May 2022, the Tesla Model 3 19x9.5" +28 TE37 Ultra M-Spec is a limited production specification available only through a handful of vendors, including Emotive Engineering. The primary difference between the +34 and +28 besides offset, is that the +28 is offered in deep-concave Face 4. The combination of the decreased offset and increased concavity make for a fantasticly aggressive look while eeking out that extra bit of inner tire clearance.
The +28 will require the right choice of tires and camber on a lowered car, but this is the perfect offset for the current batch of RAYS factory Tesla Model 3 offerings. These are, again, plug and play with the step hub machined from Volk Racing specifically to fit the Model 3 Performance!
Rollin' Big - 20" Staggered Ultra M-Spec
For most Model 3 owners with 20" Sport or 20" Uberturbines, the OEM wheels are the bain of their car's existence. While Emotive Engineering focuses on track fitment wheels in 18" and 19" diameters, we know that sometimes TE37s are statement pieces. And if you are going to put 20" wheels on a Tesla Model 3, you certainly want the strongest and lightest wheels available to make that statement.
Spec'd in 20x9.5" +22 Face-3 in front and 20x10.5" +30 Face-4 in rear, these are plug and play with the Model 3 chassis even when lowered. This allows you to fit a 265/30R20 in front and a 285/30R20 in the back to take advantage of the grip afforded by the larger wheel wells in the rear of the car. This is a limited production specification arriving in Spring of 2023 so please email for more information.
The 18x9.5" +27 Saga S-Plus
Less known to many is the 18x9.5" 5x114.3 +27 Volk Racing TE37SAGA S-Plus. Featuring a smaller wheel diameter, an aggressive offset, and Face 4 concavity, this is the track connoisseur Model 3 owner's TE37. The TE37 SAGA has engraved Volk Racing logos rather than stickers as well as spoke machining to aid in weight reduction. The S-Plus is the evolution of the SAGA line where each detail has been revised to handle the higher loads and weights of modern cars like the Model 3. S-Plus is for safety and the S-Plus will have higher rigidity and improved strength as compared to its SAGA heritage.
It's lesser known status is because this fitment is not yet stateside. The Tesla Model 3 specific 18" TE37SAGA S-Plus should come in at right around 19lbs, complete with machined step hub. Again, this is a limited production specification available through a handful of vendors. E-mail Emotive for more information!
TE Everything
Buy once, cry once. Whether you are a billionaire or a thousandaire, no one likes wasting money. All-in with wheels, tax, shipping, lug nuts, TPMS, tires, mounting and balancing, a new set of TE37s will set you back over $6,000. After tunings cars for over two decades, I have made many mistakes where buying the right part the first time would have saved me heartache, time, and money. Now that there are Tesla Model 3 specific fitments, there is no excuse to re-drill a non-M-Spec TE37. The question is truly whether you want to go "flush" or conservative.
While Emotive Engineering has a heavy focus on EV Performance, Emotive is a love of all things automotive. Emotive also carries the full line of Volk Racing Forged and Gram Lights Flow Formed lineup no matter the vehicle. If you do not see what you are looking for on the site, please reach out. Happy Motoring!
