• Goldenwrench was founded in 2019 by Mario Chan with a mission to supply modern BMW enthusiasts with high-quality accessories that reflect their unique personalities.
• The ever-popular mods have made Goldenwrench a staple among the BMW community, and now it is keen to make a similar statement in the JDM world.
• Mario’s GR Corolla bridges the gap between JDM and Euro, leveraging well-respected entities like BBS, CSF, and MBRP to help realize his vision.
• The CSF x Jackson Racing Stepped Core intercooler was a product born from development on Chan’s GRC and is a game-changer in the space.

“It’s more about the people than the cars.” This trope is something you’ll hear a lot from old heads in our industry who have “seen it all.” I admit that I’ve forged and nurtured some of my dearest friendships inside of the industry, but it’s the cars that got me here in the first place. In that sense, the people and the cars are not mutually exclusive—the two rely on each other as symbiotic entities—and the richness of the relationships we’ve made ends up refining the cars we choose to build.

Goldwrench’s latest project is a good example of this mutual benefit. Mario Chan is a friend to many of us in the industry, and we were all rooting for him when we found out he’d picked up a new GR Corolla as a SEMA project. To say the GRC space is crowded would be an understatement—it has been the apple of most aftermarket companies’ eyes since its debut—so Chan had to be quick on his feet to think differently from the crowd. Fortunately, that thought process is rather baked into Goldenwrench’s culture. Chan identified a void in the market and founded Goldenwrench in 2019 to supply modern BMW enthusiasts with high-quality accessories that would reflect their unique personalities. Five years on, Goldenwrench was ready to expand into a new audience and aimed itself squarely at Toyota’s Gazoo Racing lineup. This GR Corolla project—kitted out with a judicious selection of aftermarket mods and Chan’s own creations—would be Goldenwrench’s official announcement as a JDM player.

NOT EXACTLY NEW

Technically, Chan’s GR Corolla debuted at SEMA last year, but that takes nothing away from its total impact. Part of its SEMA transformation involved sending the car to CSF for intercooler development. Shortly after that process began, CSF seized an opportunity to team up with Jackson Racing to offer the most advanced and efficient intercooler on the market. That pursuit might’ve sounded like a bunch of typical marketing jargon, but CSF’s ambitions were proven fruitful: MotoIQ called it the best-performing intercooler it’s ever tested. No small feat, considering the OE intercooler is not considered a slouch. The stepped core design gives the CSF x Jackson Racing (8285) unit a 45% larger core volume and 73% more surface area than the OE cooler, which means immense peace of mind on those hot summer track days or stop-and-go traffic runs with the AC blasting.

GREEN AND GOLD

Pulling off the perfect JDM Euro build means getting one of the biggest names in the wheel business involved: BBS. Astute enthusiasts can nitpick the fact that the LM-R—Chan’s wheel of choice on the GRC—is manufactured by BBS Japan. But historically, BBS has been most in step with German marques. Chan was brave enough to break the mold on the GRC and recognized that the LM-R’s curvy, multi-spoke design worked well with the Corolla’s flowing body lines. And, thanks to its generous wheel well real estate, the car can accommodate generous widths (and lips to match) at every corner.

THREE TO TWO

One polarizing trend continues with JDM-bred enthusiast cars: triple exhaust tips. Some cars pull this off better than others (looking your direction, FL5 Civic Type R), but the Corolla’s mix of round and oval shapes is really off-putting to me. MBRP has been extremely accommodating to GRC owners’ tastes by offering reasonably priced dual rear exit and center exit options. Sound being equal, the latter appears to weigh less than the dual rear exit version, so I was glad to see Chan chose the “Porsche GT-esque” option (S43033CF). It’s good to see a company like MBRP diving deeper into the JDM market; it’s needed options that truly deliver “bang for your buck” value.

INTERVIEW WITH GOLDENWRENCH

We had a moment to chat with Mario Chan over the weekend about the Corolla, his favorite bits on the car, how many cars they’ll be showcasing at SEMA, Goldenwrench as a company, and where he believes it’s headed into 2025:

Goldenwrench may be better known for its BMW accessories, but over the last year or so, it’s successfully expanded outward. What was your main motivation to look outside the Bavarian marque?
I’ve always been a Toyota enthusiast at heart; the very first cars that I owned were a 2000 Toyota 4Runner (3rd Gen) and a Toyota Celica (7th Gen). So, when the A90 GR Supra was introduced—which I saw as the perfect collaboration between two of my favorite automotive brands—I knew I wanted to get to work on this unique platform with our take on supporting products for this future classic of a platform. It’s become an incredibly popular chassis for us.

Since then, our community has been vocal about wanting more support for Toyota Gazoo Racing (GR) products, and our answer has been an enthusiastic yes! We have exciting plans to expand our support to even more GR platforms in 2025.

How are you finding the GR community versus the BMW M realm that you came from?
Both communities are made up of hardcore automotive enthusiasts, each with a deep loyalty to their respective brands. What’s even more interesting is that a significant number of our customers have transitioned from owning an M car like the F8X M3/M4 to the A90/91 GR Supra. Some have even added a GR Corolla to their lineup as a dedicated track car. It’s quite fascinating to see the crossover between these passionate groups!

Speaking of passion, I saw recently that it’s your fifth year with Goldenwrench. What were some of your biggest learning lessons throughout your foundational years?
The journey over these last few years has been incredibly rewarding. It’s true what they say: time really does fly when you’re having fun! One of the biggest and most validating lessons we’ve learned in our early years is the importance of having a clear mission before starting an automotive brand, along with a team that truly believes in that mission.

I started this brand because of my personal experiences as a long-time automotive enthusiast and customer. Like many others, I faced challenges as a customer with limited resources/funds, disappointing product experiences, and frustrations after purchasing. Those experiences inspired me to take the plunge and create something meaningful, with a mission to provide a much-improved end-to-end experience for fellow enthusiasts. It’s been an incredible journey, and I’m grateful to be on it.

What’s behind the name “Keurolla”?
KEüROLLA is a fun wordplay representing ‘European Corolla’ or ‘Euro Corolla,’ which perfectly captures the essence of this build. It’s our take on what a European-inspired build design would look like applied to Toyota’s hot hatch creation. To give it an extra twist, we added the letter ‘U’ with an umlaut for a bit of a German flair. Whether or not we fully nailed the pronunciation depends on who you ask, but it definitely adds to the charm!

Ah, very clever. It makes sense now! So, what gravitated you toward the GR Corolla? Talk to us about your favorite upgrades (I know it’s not “done” so I won’t even ask if it is, haha).
As a Toyota enthusiast here in the U.S., I’ve always admired the highly sought-after GR Yaris (which the US market did not get) with its distinct design and impressive 3-cylinder AWD powertrain. I even looked into ways to import one for my personal collection! So, when the announcement came that the U.S. would get its own version in the form of the Corolla, I knew we had to build one.

It’s tough to choose a single favorite upgrade on the car because, for me, the highlight was the incredible team camaraderie throughout the process. When we first got the vehicle, we pitched the idea of creating a ‘European-styled’ Japanese hot hatch to our close build partners, and the excitement was immediate. Everyone came together, contributing their expertise and passion to make this vision a reality.

The final result is a truly one-of-a-kind GR Corolla, showcasing unique products specifically developed for this new platform by some of the biggest names in the European automotive scene. Watching this collaboration come to life was, without a doubt, my favorite part of the entire build.

I’m glad you brought up unique products because it’s so cool to see a set of BBS LM-R on the car which immediately distinguishes it from its counterparts. What was your inspiration for going against the grain here?
While it would’ve been logical to go with a Japanese wheel for this build, we wanted to stay true to the European-inspired theme. So, I reached out to my good friend Jesse at BBS with a couple of specific wheels in mind. Initially, we had our sights set on the BBS E88 or LM-R. However, due to time constraints, the E88 wasn’t feasible for this build, so we went with our second choice, the LM-R.

BBS made it happen for us, even though the sizing and bolt pattern we needed weren’t typically available in the U.S. market at the time. To give the wheels an extra European touch, we partnered with our friends at Supreme Power in Southern California to refinish the faces in a BBS White Gold finish, a color not currently offered in the LM-R lineup. The result was exactly what we were hoping for.

Talk to us about the CSF upgrades on the car. I know you were one of the first (if not THE first) to run the CSF x Jackson Racing intercooler. What were some of your first impressions/continued impressions of the kit?
Sticking with the European theme, as soon as I got the vehicle, I immediately reached out to my good friend Ravi at CSF. I knew they had to be involved in the cooling aspect of this build, given their reputation for producing some of the best cooling solutions in today’s automotive market, especially for European platforms. We sent the vehicle over to their facilities for some early scans and testing, and they went straight to work.

The end product that came to be is the CSF x Jackson Racing Stepped Core intercooler, which is an absolute cooling marvel. It’s significantly larger than the factory unit but remains lightweight while delivering temperature drops of up to 90°F. This intercooler does an incredible job of keeping the car cool, on the daily and/or at the track making the vehicle perform at its best.

The MBRP exhaust is also a cool choice. As a first-time buyer of the brand, what about it did you like? Anything you were surprised about?
MBRP is a new partner for us on this build. Their products immediately caught my attention for their unique offering and competitive price point. We’re running its center exit exhaust system, which transforms the OEM triple exit configuration into a European-styled dual-tip center exit reminiscent of what you see on a VW MK5 R32 GTI. The engineering is impressive; it even comes with block-off plates for the outer openings of the factory diffuser, giving the setup a seamless OEM look.

One of the pleasant surprises is that it retains the factory exhaust valve, avoiding any issues with lights/errors triggered on the vehicle. But what really stands out is how they’ve elevated the valve on a bracket to ensure it’s plugged in but “not in use”. This enhances the throaty sound of the three-cylinder engine at all times. keeping that signature exhaust note roaring throughout the rev range. I absolutely love this system.

With SEMA just around the corner, what do we have to look forward to with the Goldenwrench brand? And specifically, more products for the GR lineup?
This year, we’re excited to bring 13 builds to the show, and that number keeps growing each year we return to SEMA. While we’ve become known for our BMW builds, this year we’re branching out by showcasing a few Toyota and Lexus projects as well. It’s our way of demonstrating continued support and more widely supporting their vehicle lineup.

Thank you for taking the time to chat with us, Mario. We’re so excited to see Goldenwrench take another step forward in the JDM space and are big fans of what you’ve achieved so far. See you soon at SEMA!

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