TA5R users, how are these wheels holding up at the track?

[M3SQRD]

Originally Posted by IamFODI

Also curious about this. Rays and BBS forged wheels are more forged than most of the "forged" wheels on the market (which IMO are more "billet" than "forged").

Might be hard to do a real apples-to-apples comparison, though. Would have to find wheels that are made to comparable weight/stiffness/usage targets.

Please quantify what “more forged than most of the ‘forged’ wheels…”? What the hell does “‘billet’ than ‘forged’ mean”? Do you know how forged wheels are made?

[a5m]

Originally Posted by M3SQRD

Please quantify what “more forged than most of the ‘forged’ wheels…”? What the hell does “‘billet’ than ‘forged’ mean”? Do you know how forged wheels are made?

I believe they're referring to BBS and Rays being the only ones who mold forge their wheels vs others who machine forge, where they 'carve' a wheel out of a forged billet.

[IamFODI]

Originally Posted by a5m

I believe they're referring to BBS and Rays being the only ones who mold forge their wheels vs others who machine forge, where they 'carve' a wheel out of a forged billet.

IDK if BBS and Rays are the only ones, but yeah, this is more-or-less what I meant.

Here's my understanding, likely oversimplified and put in non-expert terms. Happy to have any necessary corrections.

"Billet" generally means the final shape is defined mainly by machining of the billet.

"Forged" is supposed to mean the final shape is defined mainly by the forging process.

All of this is shades of gray, of course. There's no bright line. Like all forged parts, forged wheels always start with a forged billet and end with machining. But there are usually intermediate forging steps to bring the billet closer to the final shape before machining (or to bring a partly machined item closer to the final shape before machining further). Those intermediate steps are where differences can exist between manufacturing processes, and they're why "billet" vs. "forged" is really a spectrum rather than a binary classification.

If one were to simply machine a completely blank billet into a wheel, the grain structure would be whatever was in the billet rather than what would be best for the finished wheel. The result might still be better than a cast or flow-formed wheel, but it wouldn't be optimal.

Additional forging steps can allow more control over the grain structure, potentially bringing it closer to what the finished product needs.

Rays and BBS do more of/with those additional forging steps than many other manufacturers do, which is one reason why their wheels tend to be stronger and/or lighter and/or stiffer (and WAY more expensive) than many other options.

OTOH, brands like Apex use simpler processes to make their forged wheels, which is why those wheels are cheaper than the high-end forged ones while still being better than flow-formed or cast wheels.

"More forged" and "more billet" are crude and slightly flippant ways to make that distinction.

[M3SQRD]

Originally Posted by a5m

I believe they're referring to BBS and Rays being the only ones who mold forge their wheels vs others who machine forge, where they 'carve' a wheel out of a forged billet.

Very simplistic view of how forged wheels are made. The weakest part of any forged wheel is formed the same way. You don’t machine “carve” the barrel and the tire seat/foot on the wheel. Just give Forgeline a call who makes wheels for almost all professional race series.

[a5m]

Originally Posted by M3SQRD

Very simplistic view of how forged wheels are made. The weakest part of any forged wheel is formed the same way. You don’t machine “carve” the barrel and the tire seat/foot on the wheel. Just give Forgeline a call who makes wheels for almost all professional race series.

Not sure what the argument is here. Never claimed to be an expert, just stating facts and curious on how various forged wheel manufacturing processes impact their ability to withstand abuse.

Speaking of which, can't wait to put my TE's on.

[trebm3]

Originally Posted by tdott

Could be due to different tracks, speeds, level of experience.

Driving miss daisy sure, you can go decades without bending a wheel. But at higher speeds and in competition it's fairly easy to bend a wheel or two, esp if you have an off. Sebring a track I frequent is known to be a bumpy track with punishing curbs, could be the reason...

How often? Not that often, back in 2012 - 2016, I had a set of Apex Arc8s, two had slight bends, nothing major, balanced out but annoying on the highway drives. 2017 - 2023 had a set of Ta5r, similar issue two had slight bends, nothing major, balanced out but annoying on the highway drives. 2023 - current, vs5rs holding up well so far, had more abuse than the previous two sets (became an instructor/more frequent track days + started time trials competition).
Ask any w2w racer, bent wheels are fairly common even forged sometimes.....

Interesting. I guess WRL race driving and literally hundreds of laps at COTA isn't good enough. I frequent a lot of tracks around Texas like MSR, ECR etc and I guess I haven't seen the crazy curbs you're running into. To Each their own I suppose.

[M3SQRD]

Originally Posted by a5m

Not sure what the argument is here. Never claimed to be an expert, just stating facts and curious on how various forged wheel manufacturing processes impact their ability to withstand abuse.

Speaking of which, can't wait to put my TE's on.

It’s not really an argument. I’m just trying to explain where wheels are failure critical or fatigue critical or fracture critical. The wheel face is not, if correctly designed, a critical part of a wheel design so “machining” vs. “forging” makes no meaningful difference. The wheel face is stiffness critical, if shooting for minimum weight, and both methods result in the same stiffness.

Volks are awesome wheels. I had a set of the original TE37 in bronze on my Spa Yellow s2000. You’ll love them.

[tdott]

Originally Posted by M3SQRD

You stated your experience level and usage of curbs equates to more bent wheels especially if they are flow formed wheels. You initially said TA5R wheels “bent 2 fairly easily on curbs IMO”

Originally Posted by trebm3

I guess I haven't seen the crazy curbs you're running into. To Each their own I suppose.

Originally Posted by tdott

Could be due to different tracks, speeds, level of experience.

Combative bunch here, life must be boring.
I guess no one ever bends wheels here. Carry on.

[tdott]

Originally Posted by a5m

Wonder how Rays and BBS fare

BBS is usually pretty strong, but I have heard of owners that have managed to bend them.

Edit, added in some posts hopefully showing that bent wheels are not uncommon at the track and that any wheel will bend with a hard enough impact.

[a5m]

Originally Posted by tdott

BBS is usually pretty strong, but I have heard of owners that have managed to bend them.

Edit, added in some posts hopefully showing that bent wheels are not uncommon at the track and that any wheel will bend with a hard enough impact.

Yea aren't the infamous E88's known for bending? Maybe they're generally beat on more compared to other wheels. Perhaps the multi-piece design's purpose is to make em serviceable.

[M3SQRD]

Originally Posted by tdott

Combative bunch here, life must be boring.
I guess no one ever bends wheels here. Carry on.

Yep. You nailed it. Life is boring. I’ll clear this up - wheels do bend and they also have a finite life even if they don’t bend. I replace track wheels after a certain number of track days.

[jmeenach]

Originally Posted by a5m

Yea aren't the infamous E88's known for bending? Maybe they're generally beat on more compared to other wheels. Perhaps the multi-piece design's purpose is to make em serviceable.

I've heard it's common(ish) to bend E88 barrels. No personal experience, though. One of the reasons I didn't buy them. The lead time, cost, and repair combined made me decide it was easier to pay a discounted price to replace a bent Apex.

[bigjae1976]

The only wheel I've heard of and seen consistent issues are the D-Force LTW5s which I have nicknamed the widowmaker. I've seen two where the barrel separated from the spoked.

Over 14 years of running and seeing other people run Apex flow formed wheels, I have not seen one fail catastrophically on track. My buddy seems like bending and cracking his wheels but they are probably 10 year old wheels. I have had about 40 apex wheels over the years and have yet to bend one of them.

So if you're bending a bunch of wheels you're doing something wrong.

[omgzirra_exe]

Originally Posted by a5m

Yea aren't the infamous E88's known for bending? Maybe they're generally beat on more compared to other wheels. Perhaps the multi-piece design's purpose is to make em serviceable.

Originally Posted by jmeenach

I've heard it's common(ish) to bend E88 barrels. No personal experience, though. One of the reasons I didn't buy them. The lead time, cost, and repair combined made me decide it was easier to pay a discounted price to replace a bent Apex.

E88s are motorsport wheels designed with minimum weight as the priority. Because of that, the barrel is intentionally lighter and structurally weaker than a typical street wheel. It is considered a consumable component, especially in high-load racing environments.

Since they are three-piece wheels, it is usually more cost-effective to rebuild or replace individual components (typically the barrel or lips) instead of buying an entirely new set of forged wheels.

For street use, the E88’s design philosophy carried over into the RT88. The RT88 keeps a similar face but uses a much heavier and stronger BBS LM-style barrel. This adds durability for daily driving, though it does sacrifice some of the weight savings.

Originally Posted by a5m

Not sure what the argument is here. Never claimed to be an expert, just stating facts and curious on how various forged wheel manufacturing processes impact their ability to withstand abuse.

Speaking of which, can't wait to put my TE's on.

Originally Posted by M3SQRD

Very simplistic view of how forged wheels are made. The weakest part of any forged wheel is formed the same way. You don’t machine “carve” the barrel and the tire seat/foot on the wheel. Just give Forgeline a call who makes wheels for almost all professional race series.

You're correct that most forged wheels, even from top-tier brands like Rays, BBS, or Forgeline, typically use a similar barrel-forming process. Generally, manufacturers spin-form the barrel rather than machining it from solid aluminum. This spinning process aligns and elongates the aluminum’s grain structure around the rim, significantly improving strength and fatigue resistance.

For context, my background includes extensive experience in manufacturing carbon fiber components, as well as aftermarket wheels including flow-formed and multi-piece forged wheels. Our wheel manufacturing processes were similar to Enkei's MAT approach, but our designs and structural tests were conducted entirely in-house using specialized software.

When comparing wheel manufacturers, I'll highlight two well-known OEM suppliers: Rays (Volk Racing) and Enkei.

Rays / Volk Racing – Fully Forged Process
Most forged wheel manufacturers, including Rays, start with similar high-quality aluminum billets (typically 6061 alloy). Rays sets itself apart through their specialized forging process:

- Billet Heating

Billets are heated to over 500°C, allowing uniform shaping without introducing unwanted stress.

- Multi-Stage Mold Form Forging

Heated billets undergo proprietary mold forging under extreme pressure (up to 5 tons per square centimeter). This precisely aligns grain structure with the final wheel shape, enhancing strength and durability.

- Shuttle-Type Die Forging (Spokes and Hub)

Rays employs specialized dies pressing from multiple directions to form hollow and U-shaped cross-sections, reducing weight while maintaining structural integrity.

- Barrel Spinning

The rim section is spun while still heated, further aligning grain flow to improve fatigue resistance and strength.

- Machining, Heat Treatment, and Finishing

After forging, wheels undergo precision machining, heat treatment (quenching and tempering), shot peening, and corrosion-resistant coatings.

- Rigorous Quality Control

Every wheel receives thorough inspections using eddy-current and X-ray testing, exceeding standard industry requirements.

In short, Rays' extensive forging and testing processes produce wheels we consider the best (subjectively) because they are light, strong, and durable... and for those reasons make great track wheels.

Enkei – MAT (Most Advanced Technology)
Enkei uses a hybrid approach combining casting and rim spinning known as MAT:

- Casting

Molten aluminum is initially poured into molds to create the basic wheel shape.

- Rim Spinning (MAT)

Only the rim area of the cast wheel is spun and rolled afterward. This strengthens the grain structure specifically in the rim, providing some forged-like benefits without applying it throughout the entire wheel.

- Heat Treatment and Finishing

Wheels then undergo heat treatment, precision machining, and corrosion-resistant finishes.

- Spec-E Testing

Enkei applies rigorous Spec-E testing standards, surpassing typical JWL industry tests, to ensure reliability and performance.

The key distinction is that Enkei's MAT process primarily benefits the rim area. The face, spokes, and hub remain cast, meaning MAT wheels offer significant improvements over fully cast wheels but don’t achieve the full structural benefits of a fully forged wheel.

Most forged wheel makers use the same high-quality 6061 aluminum, so the real differences come from how each brand forges, finishes, and tests its wheels. Rays relies on an intensive multi-stage forging process that aligns grain structure throughout the entire wheel, then backs it up with strict X-ray and eddy-current inspections. The result is maximum strength, low weight, and high fatigue resistance. Enkei’s MAT method casts the wheel first, then spin-forms only the rim section.

For custom wheels (What we did), almost everything starts in CAD: engineers model the face, load it in FEA software, and confirm the design meets required load targets. Once approved, a billet blank goes to a CNC mill, which cuts the face profile. From there:

Two-piece wheel – the machined face and the spun barrel are welded together.

Three-piece wheel – the face, outer lip, and inner barrel are bolted together with seals or gaskets.

Regardless of the configuration, barrels are always spin-formed, not fully machined. Spinning expands the heated aluminum, aligns grain flow around the rim, and delivers better strength and impact resistance than cutting the barrel from solid stock.

TLDR: Wheels are a wear item. Even if they are structurally sound for years, material fatigue will eventually affect them, just like it does with engines. Forged or not, nothing lasts forever. If you track your car, expect to replace wheels at some point. At the end of the day, no matter how fancy your $5K wheels are, a 2-foot deep pothole always wins.

[omgzirra_exe]

Just a quick note on other forged wheels:

Plenty of brands forge only the face from a billet, then attach a separately spun barrel. The two pieces are typically joined with friction-stir welding, where they spin together under pressure until the aluminum fuses. While this produces a strong joint and keeps tooling costs down, it is not the same as a true one-piece monoblock, where the face, spokes, and barrel are forged from a single billet, as Rays does.

Rays and a handful of other OEM-level suppliers invest in massive forging presses and multi-stage dies that forge the entire wheel in one operation. This full monoblock approach maintains uninterrupted grain flow through the face, spokes, and barrel, giving the wheel the highest possible strength-to-weight ratio. Two-piece welded designs can still be strong, but they do introduce a grain break at the weld line.

Regardless of construction style, barrels are spin-formed rather than fully machined. Spinning expands the heated aluminum, aligns grain flow around the rim, and provides better impact resistance than cutting the barrel from solid stock.

[a5m]

Such good info omgzirra_exe, thank you, especially coming from someone with your background. Gotta sit down and read your posts again properly. Makes me appreciate forged wheels like Rays more that's for sure.

[kolosy]

Mic drop

Was drooling over mikerunt ‘s forgelines in the FS forum but maybe I do need some te37s in my life.

[omgzirra_exe]

Originally Posted by a5m

Such good info omgzirra_exe, thank you, especially coming from someone with your background. Gotta sit down and read your posts again properly. Makes me appreciate forged wheels like Rays more that's for sure.

I love wheels; they’re fun to geek out over.

I skipped the heavy technical jargon, but this should give you a clear idea of how two of the biggest OEM suppliers do things. I might have missed a detail here or there, and I’m no certified expert. Just a hobbyist who turned the hobby into a job for a short period.

Originally Posted by kolosy

Mic drop

Was drooling over mikerunt ‘s forgelines in the FS forum but maybe I do need some te37s in my life.

Forgeline wheel are really good, I wouldn't hesitate to get their stuff.

huge fan of the 8twelve guys, their stuff is really great forged monoblock. Also made in the USA.

https://8twelvewheels.com

[mikerunt]

Originally Posted by kolosy

Mic drop

Was drooling over mikerunt ‘s forgelines in the FS forum but maybe I do need some te37s in my life.

18x11 with brand new R7s! Come grab them!

[M3SQRD]

Originally Posted by omgzirra_exe

For context, my background includes extensive experience in manufacturing carbon fiber components, as well as aftermarket wheels including flow-formed and multi-piece forged wheels. Our wheel manufacturing processes were similar to Enkei's MAT approach, but our designs and structural tests were conducted entirely in-house using specialized software.

What actual structural test methods were used to qualify your wheel designs for the various loading environments wheels are subjected to? Are accelerated life tests performed to assess fatigue life (or fracture life because human life is involved)? Do you perform NDE before and after testing? Manned space missions require detailed fracture assessments of primary and secondary structural components/assemblies. How was specialized software used in wheel structural qualification testing? Some form of real-time processing of collected test data? Correlation or comparison between test data and analytical predictions?

[omgzirra_exe]

Originally Posted by M3SQRD

What actual structural test methods were used to qualify your wheel designs for the various loading environments wheels are subjected to? Are accelerated life tests performed to assess fatigue life (or fracture life because human life is involved)? Do you perform NDE before and after testing? Manned space missions require detailed fracture assessments of primary and secondary structural components/assemblies. How was specialized software used in wheel structural qualification testing? Some form of real-time processing of collected test data? Correlation or comparison between test data and analytical predictions?

Trying to remember all this after a 5 pm to 11 pm nap is rough… lmao. So bear with me here, I might not get everything perfect.

You asked how we qualify our wheels for loads, fatigue life, fracture resistance, NDE, software validation and real-time data correlation. Here’s the full process, from certified blanks through final approvals and weight-saving options.

I hope this make sense...

None of our wheels or prototypes are fully made in the U.S. All forging, accelerated life testing and non-destructive evaluation happen overseas at suppliers with the presses, tooling and lab facilities needed. That is why a true custom monoblock forged wheel set made domestically usually starts around $1,500 per wheel (about $6,000 for four) and can exceed $15,000 once you add custom finishes or machining steps. The highest price often reflects customers choosing Dymag carbon-fiber barrels and sizing (more material obv)

Structural test methods
Our barrel supplier delivers blanks that have already passed drum-fatigue, corner-fatigue and impact-drop tests. Once we receive those certified blanks we machine a prototype batch to final spec and repeat the same accelerated life tests in-house. Radial drum fatigue runs 500,000 to 1,000,000 rotations. Cornering fatigue cycles run 100,000 to 200,000 times. Impact-drop testing simulates a high-speed curb or pothole strike.

Accelerated life testing and fatigue life
Each fatigue test uses safety factors above expected peak loads to approximate long-term durability in a short time. Impact-drop tests assess fracture resistance under severe conditions. These tests ensure human safety margins are met.

Non-destructive evaluation
Before any destructive testing the blanks undergo X-ray or CT scan inspection to verify no porosity. After fatigue and impact tests we perform eddy-current or dye-penetrant inspections to detect micro-cracks. During production we spot-check every batch using the same methods on a set schedule.

Use of specialized software
All wheel geometry is modeled in CAD and validated with finite-element analysis. We run three primary load cases: lateral cornering, radial vertical and torsional braking or acceleration. Fatigue-life prediction methods include rainflow cycle counting and Miner’s rule.

Real-time data processing and correlation
Prototypes are instrumented with strain gauges and load cells that record load, deflection and temperature in real time during destructive tests. We immediately compare those results to FEA predictions. If correlation falls outside our tolerances we adjust geometry or wall thickness and repeat the test cycle until simulations and physical data align.

Final qualifications and controls
Finished wheels must meet JWL and VIA standards or stricter in-house specs such as Rays Plus-R or Enkei Spec-E. For our EU market meeting TUV requirements is our biggest challenge and we have destroyed many wheels to satisfy their load, cycle and impact criteria. Every production batch is dimensionally scanned for run-out and concentricity and statistical samples undergo air-leak, radial-load and surface inspections before shipment.

Weight-optimization options
As a finishing step we offer scalloping and I-beam profiling. These CNC operations remove material from low-stress areas guided by FEA stress maps so only safe regions are thinned without compromising strength. A good example is the BBS FI-R wheel which combines scalloped pockets around each spoke tip with I-beam-shaped spokes. The pockets trim rotating mass where stress is lowest while the I-beam profile adds bending resistance and stiffness with wide flanges on either side of a thinner central web.

Now I might not have described every detail perfectly but I can run this by my former boss and our lead engineer to make sure it is spot on.

I should just ask my wife, she has a masters in Material Science lol.

ANYWAYS TLDR;
We start with blanks tortured overseas, then we machine them, smash them in drum-fatigue and curb-strike tests, X-ray and dye-penetrant inspect them, geek out in CAD and FEA with live gauge data, earn JWL, VIA and TUV approvals, and finally carve in scallops and I-beams for extra lightness (IF requested, adds a lot of $$ though). A lot of work for pot hole to hurt my feelings later.

[M3SQRD]

omgzirra_exe

It all made perfect sense

I wasn’t expecting such a detailed response! I can’t think of anything you’ve left out starting with a clean sheet design to a final design ready for production and everything required in between. Thanks.