The RAYS VOLK RACING TE37 ULTRA extends the TE37 family's engineering DNA into a dimension the original wheel never addressed: large-diameter, high-PCD fitment for premium performance cars and capable SUVs. Introduced in 2014, the TE37 ULTRA was RAYS Engineering's answer to demand from Porsche 911 owners, BMW M-series enthusiasts, and performance SUV drivers who wanted the TE37's forged monoblock pedigree without compromising the offset and hub dimensions their vehicles require. The result is a wheel that carries the six-spoke TE37 identity visually while incorporating the structural and dimensional reinforcements demanded by heavier, higher-torque platforms.
The TE37 ULTRA M-SPEC designation refers to a specific spoke and hub geometry variant developed for BMW M-series applications, with calliper clearance optimised for M Sport and M Performance brake systems. Standard TE37 ULTRA and M-SPEC variants are both available through our sourcing programme.
Premium performance vehicles frequently carry unique dimensional requirements — Porsche's 5×130 bolt pattern on 20" diameter, BMW M's recessed hub face, or the oversized centre bore of certain Audi RS models. Our team maintains current specifications for TE37 ULTRA variants across all major European performance platforms and can confirm fitment before order placement. We also offer an AI Wheel Design Service if you want a custom spoke pattern or finish concept designed before committing to production.
The TE37 ULTRA is purpose-designed for premium performance platforms that exceed the typical parameters of compact sports car applications. Confirmed popular fitments:
European platform hub-centric rings are included with applicable orders. Staggered fitment sets require separate front and rear size specifications — contact [email protected] for staggered-set pricing.
The development brief that produced the TE37 ULTRA in 2014 was straightforward to articulate but technically demanding to execute: maintain the structural integrity and visual identity of the TE37 while scaling all dimensions to accommodate premium performance vehicles with larger wheel diameters, higher vehicle weights, and more powerful braking systems. RAYS Engineering's challenge was that the TE37's original design was optimised around 15"–18" diameters for Japanese sports cars weighing 1,000–1,400 kg. A Porsche 911 Turbo S weighs 1,640 kg and corners at lateral g-forces a Civic cannot approach; a BMW M5 Competition generates braking torques that would test any wheel's hub-face integrity.
RAYS addressed this by engineering the TE37 ULTRA with significantly thicker spoke roots and a reinforced hub-face casting that incorporates material in the spoke-hub transition zone specifically calculated to handle the increased torque and bending moments of large-displacement, high-torque platforms. The spoke geometry was reshaped to maintain the TE37's visual proportions at 19"–22" diameters without appearing bloated — a subtle but technically important exercise in scaling spoke width, depth, and separation to preserve the visual rhythm of the original design at larger diameters.
The M-SPEC variant, developed in direct collaboration with BMW M performance program teams, incorporated specific calliper clearance measurements taken from BMW M Sport and M Performance brake packages to guarantee zero interference fitment on M2, M3, and M4 applications with upgraded braking systems. This level of platform-specific engineering is characteristic of RAYS' approach to premium segment products.
Forging wheels at 20"–24" diameters presents challenges that do not exist at 17"–18": the die size and press tonnage required scale non-linearly with diameter, and the aspect ratio of spoke length to cross-section becomes more extreme as diameter increases. RAYS' Shizuoka facility was upgraded with a larger-capacity forging press specifically to accommodate TE37 ULTRA production in the 20"–24" range — an investment that reflects the company's commitment to maintaining full-factory production quality across the premium segment.
Post-forging CNC machining on the TE37 ULTRA employs the same 5-axis milling centres used for smaller RAYS products, with toolpath programming specifically developed for the TE37 ULTRA's larger spoke lengths. The dimensional precision achieved — ±0.05mm across spoke faces — ensures the kind of balance performance expected by owners of Porsche and BMW vehicles, where wheel-induced vibrations are especially perceptible due to those vehicles' exceptional chassis communication.
| Model | Construction | Weight 20×9.5J | Platform | Max Diameter |
|---|---|---|---|---|
| RAYS VOLK RACING TE37 ULTRA | Forged monoblock | ~9.8 kg | Porsche/BMW M/AMG | 24" |
| BBS FI-R | Forged monoblock | ~10.5 kg | BMW/Porsche/AMG | 21" |
| HRE Flowform FF01 | Flow-formed | ~10.2 kg | European GT | 22" |
| Forgeline GS1R | Forged monoblock | ~10.0 kg | GT/track | 21" |
Staggered Porsche fitments, unusual M-series offset combinations, and supercar-specific specifications are all achievable. Hodoor offers a custom forged wheel manufacturing service with direct RAYS Japan production access for non-catalogue TE37 ULTRA configurations. You can also use our AI Wheel Design Service to visualise your concept before production begins.
Q: What is the difference between TE37 ULTRA and TE37 ULTRA M-SPEC?
A: The M-SPEC (M-Specification) variant incorporates a modified inner hub-face geometry and spoke inset specifically engineered to clear BMW M Sport and M Performance brake callipers in 19"–20" applications. The standard TE37 ULTRA uses a universal geometry that may require spacers or professional fitment verification on BMW M models with upgraded braking systems. If you drive a BMW M vehicle, specify M-SPEC at order placement.
Q: Is the TE37 ULTRA appropriate for Porsche 911 GT3 RS?
A: The TE37 ULTRA is dimensionally compatible with Porsche 911 applications in 5×130 bolt pattern. For GT3 RS with carbon-ceramic brakes, calliper clearance verification is essential before ordering — contact our fitment team with your exact calliper specification. Note that Porsche centre-lock variants require a different conversion; standard five-bolt TE37 ULTRA is for conventional Porsche bolt pattern cars only.
Q: Does the TE37 ULTRA come with extended hardware for BMW hub-centric fitment?
A: Yes, European market TE37 ULTRA orders for BMW applications include hub-centric rings bridging from 73.1mm to BMW's hub bore. Extended bolts or adapter plates are not required for standard BMW fitments; they are bolt-on compatible with OEM BMW wheel bolt specifications.
Q: What is the maximum load rating of the TE37 ULTRA in 22" diameter?
A: RAYS publishes JWL-compliant load ratings with each product. For 22" applications, the TE37 ULTRA is rated for vehicle axle loads consistent with production GT cars including Porsche Cayenne and BMW M5. For exact load rating figures applicable to your specific vehicle and tyre combination, contact our technical team.
Hodoor World serves discerning buyers who demand RAYS Engineering quality on premium European and Japanese performance platforms. Our catalogue includes RAYS VOLK RACING, Brixton, Forgeline, Work Wheels, and other world-class forged wheel manufacturers. Visit hodoor.world for the full collection.
TE37 ULTRA wheels on premium vehicles deserve premium maintenance protocols:
Hodoor World delivers RAYS VOLK RACING TE37 ULTRA sets globally. Large-diameter sets for European platforms are a logistics speciality — we ship to Germany, UK, Switzerland, France, USA, Canada, and all major markets with DDP service available. In-stock orders dispatch in 2–5 business days; special configurations from RAYS Japan production take 8–12 weeks. For staggered sets and non-catalogue specifications, contact [email protected] for consolidated freight options that reduce per-wheel shipping cost.
