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Time to Rethink Your Cooling System: The True Power of "EVOLVE" to Dominate Midsummer. Have you ever felt a cold sweat watching your water temperature gauge during a summer traffic jam or a track run? Turn the Intense Heat to Your Advantage: The "EVOLVE" Performance Radiator That Supports Your Summer Drives. With the peak of summer fast approaching, are you worried about your car’s water temperature gauge? Whether you’re pushing through continuous laps at the circuit or navigating stop-and-go traffic in the scorching heat, ensuring your engine performs at its best requires a solid cooling system. The "EVOLVE" series, which HPI continues to refine, is more than just an increase in capacity; it is a "crystallization of technology" designed to control coolant flow and push core performance to its absolute limits. 1. Beyond "Cool": The Overwhelming Heat Dissipation of Micro-Pitch Fins At the heart of every EVOLVE radiator lies our "Micro-Pitch Fin" technology. By precisely designing the fin shape and increasing the number of core tubes by approximately 20%, we have maximized the surface area for contact with airflow. This high-density design effectively captures every breeze to whisk away heat, enabling stable water temperature maintenance even in the most brutal conditions. 2. Uniform Flow Changes Performance: The "Control Plate" In vehicles with an upper-and-lower or side-hose layout, uneven coolant flow means you are only utilizing a fraction of your cooling capacity. HPI’s uniquely developed "Internal Control Plate" is a magical component that regulates flow within the upper tank, ensuring the coolant circulates evenly throughout the entire core. This eliminates "hot spots" where heat tends to accumulate, allowing you to utilize the entire surface area of the core without waste—a result of our relentless pursuit of efficiency. Visual proof of superior cooling: Thermographic analysis demonstrates how the HPI Control Plate ensures uniform coolant flow, eliminating temperature variations across the entire radiator core. 3. Three Options to Match Your Driving Style We offer three series tailored to your needs, from the circuit to the street: STD Series: Features a large-capacity core with overwhelming thermal capacity, handling long, hard drives with ease. LIGHT SH Series: An all-around model that achieves a high-level balance between street drivability and circuit cooling performance. MULTI FLOW Series: Our top-tier model that optimizes coolant circulation via a side-tank structure, managing residence time to achieve exceptionally stable water temperatures. 　　　　　　　　　　　　　　　　　　　　View Specs & Compatibility HPI EVOLVE Radiator Performance Data: A comparison of cooling efficiency between the EVOLVE STD, Light SH, and Multi Flow series under circuit driving conditions at Sodegaura Forest Raceway. Engineered for performance icons: The HPI EVOLVE radiator featuring Micro-Pitch Fin Tech and superior flow control. Engineering Insight: PROTO’s Perspective "For EVOLVE, the aspect we were most uncompromising about was the 'joint between the fins and the tubes.' Even the slightest misalignment can ruin the original heat dissipation performance of the Micro-Pitch Fins. That is exactly why we make zero compromises in our welding process. Honestly, there are moments when we struggle with the balance of production efficiency and cost. But we want the drivers who choose our Performance Radiator to enjoy full-throttle runs at the circuit without ever worrying about their water temperature. Delivering 'peace of mind' and the 'ultimate driving experience'—that is the pride of HPI.” HPI designs each radiator with an optimal configuration tailored to the specific thermal characteristics of every vehicle, ranging from legendary cars such as the AE86, JZX100, S15, and BNR32 to the latest models. Series Primary Applications Price (excl. tax) STD JZX100/110, S15, FD3S, etc. from 65,000 JPY SH AE86, BNR32, JZX100/110, etc. from 65,000 JPY MF JZX100, BNR32, ZN6, etc. from 90,000 JPY Note: Models compatible with water temperature sensor attachments are widely available. Voice of HPI Users We would like to thank our customers for sharing their experiences. JZX100 (Chaser) Owner: "I used to have to pause for cool-down laps constantly because my water temperature would spike when drifting in 1st and 2nd gear. Since switching to EVOLVE, the temperature rise is noticeably milder. I’m spending less time cooling down and more time actually driving. Plus, the finish on the tank is stunning—I love opening my hood now!" S15 (Silvia) Owner: "I used to back off the throttle the moment I saw the temperature needle climbing during circuit runs. But with my HPI radiator, the temperature stays rock-solid even when I’m pushing it hard. Those who drive aggressively will immediately notice the difference in peace of mind." AE86 (Trueno) Owner: "Driving a classic car in summer traffic used to make me nervous. I chose the LIGHT SH model because I heard it was lightweight, and it has genuinely made managing water temperatures so much easier. It was a direct fit for my sensors, saving me a lot of hassle, and now I can enjoy driving even in the heat of summer with total confidence." Closing Message Your cooling system is the final line of defense for your engine and the greatest weapon to support your performance. This summer, equip your car with the trust that comes with the name "EVOLVE." The full aluminum HPI EVOLVE radiator—precision-engineered for maximum thermal efficiency and engine reliability. Looking to further enhance your cooling efficiency? Check out our oil coolers as well! For inquiries or price quotes, please visit:

Today, June 24th, marks HPI’s anniversary. Since our founding in 1998, we have been running for 28 years. To celebrate this milestone, we are launching a special project🎂 ACE, HPI's passionate test pilot and mascot. Interviewer Introduction: ACE The hot-blooded test pilot and mood-maker of HPI! With his signature catchphrase, "With these parts, I can push it even harder!" ACE is a cool robot in red and black. A drift master who pilots an S15 Silvia, he loves racing and passionate driving above all else. At events, no one speaks about HPI’s "passion for driving" with more fervor than ACE— he truly is HPI's ace. Ryusaku Hitomi x ACE: A Special Talk ACE: Every day, I push machines to their limits on the test track, feeling in my very core how much a single part can change a car’s performance. That’s exactly why I wanted to touch the "root of the strictness" behind the President’s approach to craftsmanship. President Hitomi, could you spare a moment? I want to hear about your roots! Hitomi: That’s an interesting project. Sure, why not? My interest in "moving things" started when I was 10 or 11 years old. I was fascinated by the way a chain moved over a sprocket, and I wanted a bicycle so badly. Since my family were farmers, I helped out with the farm work to earn one. Then, I encountered another "moving thing"—a tractor. It was so mysterious. It obviously had an engine, but you couldn’t see it from the outside. So, even though I was just an elementary school kid, I climbed in and managed to drive it somehow. Eventually, I got that bicycle I wanted, but I immediately took it apart piece by piece. I just wanted to understand the mechanism as fast as possible. I never thought about how to put it back together, so I ended up with a pile of parts and no idea where they went. My parents were stunned. (Laughs) ACE: A tractor in elementary school! So that’s where the same obsession with machinery that we have today was ignited. That gives me chills! Hitomi: Exactly. When I was 11 or 12 years old, my older brother bought a motorcycle. Instead of asking for a ride, my first thought was, "I want to take that apart, too." Our farmhouse shed had all the tools needed for tractor maintenance, so I snuck in and dismantled his motorcycle behind his back. Again, I didn't think about reassembly, and it had far more parts than the bicycle. My brother was furious when he found out— I got the beating of a lifetime. (Laughs sheepishly) ACE: I see. For you, disassembling was a process of understanding. It’s the same way I read a machine’s behavior on the circuit. What was the first car you owned, President? Hitomi: I bought a used Kawasaki W1 back when it was at the absolute peak of its popularity. It was delivered on a Saturday, and I was planning to take it out for a real ride on Sunday. After a quick test ride around the neighborhood, I was washing it, feeling absolutely pumped. Then, a friend who loved bikes came over and asked, "Let me ride it." I hadn’t even really ridden it myself yet, but I let him take it, and I hopped on the back for a tandem ride. We ended up getting into an accident and totaled the bike. I didn't even have a chance to take it apart. I was unconscious for two days because of that crash, and I learned my lesson— I swore to myself right then that I was done with motorcycles. ACE: Oh my... totaled the day after delivery, and unconscious... It’s hard to imagine the President like that today. But perhaps the reason HPI products are so obsessed with "safety" and "reliability" is rooted in that very experience. After swearing off bikes, why did you choose to go back to "driving" and “manufacturing"? Hitomi: After I graduated from high school, I rented a room in Setagaya, Tokyo, and got a job at a Toyota dealership. Even though I was working for Toyota, my first real car was a Mazda Presto Rotary. I used it for commuting every day and went out driving every single night. Back then, "tuning" basically meant welding the differential, and since you couldn't just buy wide wheels, we’d modify steel rims— what we called "steelie wides.” (custom-widened steel rims) We just drove the streets with pure guts. I formed a team with a few guys, and we’d go touring together. I still vividly remember the "Aoyama Zero-Yon"(the local drag racing scene) meets back then—Mr. Amemiya (Representative of RE Amemiya) would be there too. Whenever the man they called the "God of Rotary" showed up, the whole atmosphere at the venue would explode with energy. He had that kind of overwhelming presence even back then. ACE: Starting from modifying steel wheels is truly the origin of ingenuity. Hearing about your encounter with Mr. Amemiya really captures the intensity of those days. I’ve heard that back then, people used to say, "Hitomi’s driving is on the edge." Hitomi: Yeah, I became famous on Route 246 for having "edgy driving." Back then, I was just obsessed with speed, but driving on public roads always carried danger. After witnessing two life-threatening accidents, I realized something profound: "True speed and technology can only be pursued in a protected environment." That’s when I decided to graduate from street racing and challenge myself in the world of formal racing. ACE: I see. You channeled your passion for speed into a path of safety and technological innovation. Knowing the weight of a human life is what created HPI’s current "commitment to performance." That’s such a deep story. Hitomi: First, I went to Fuji Speedway just to see what racing was like. I had no money, so at first, I watched from outside the guardrail. The first thing I saw was a 240Z (S30) tearing up the track. I was shocked. I later found out it was just a test run. Seeing that, I was so moved by how incredible racing cars were. I saved up money, finally got onto the circuit, and was blown away by the size of the main grandstand! The track was so wide, I thought, "Maybe I can do this too." That was the spark. ACE: From watching from behind the guardrail to standing on that very field— it’s amazing to think that HPI parts today were born from that "shock" you felt that day. It really makes my heart race. Hitomi: Anyway, I bought a KE10 Corolla to start racing. Four of us formed a privateer team and rented a garage near the circuit. We spent every weekend there for maintenance and practice. I entered the "Freshman" class, but I couldn't reach the top. Back then—and even now—well-funded teams are just strong. They have the leeway to blow an engine and still keep going. I realized, "I have to do this for real." I quit my job and started working part-time for a transport company. Why? Because I figured I could borrow a truck to transport the race car and save costs. I poured almost my entire salary into racing and gained experience as a driver. In the middle of all that, I had my race engine tuned by a place called Fukagawa Internal Combustion (Fukagawa Nainenki), and that’s where I had a fateful encounter that changed my life. Where it all began: President Hitomi’s first car, the Mazda Familia Presto Rotary. A dedicated mechanic fine-tuning an engine, capturing the detail and focus required for high-performance automotive maintenance. ACE: To beat the big-budget teams, you shaved away your own efforts, sharpened your wits, and through dialogues with professionals like Fukagawa Internal Combustion, pushed the machine’s potential to the absolute limit. President, thank you for sharing your incredibly passionate origins! ACE: Everyone, this is just the beginning of the President's roots! Next time, we’ll dive into the adventure called "Founding the Company," where the President's life takes a dramatic turn. Stay tuned for the next installment of this special talk between President Hitomi and me, ACE, where we touch the very core of "HPI’s roots." HPI will continue to accelerate our "passion for driving" with all of you! 🏎️🔥 (Note: The street driving mentioned in this article reflects the traffic environment and social context of that era. It should not be interpreted as acceptable under modern traffic laws or safety standards. HPI prioritizes strict adherence to traffic regulations and promotes only safe and legal motorsports activities.)

Following the positive response to our first anniversary special, we are thrilled to continue this journey into the heart of HPI. In this final part of Ryusaku Hitomi x ACE: A Special Talk, we look back on the journey and share the concluding thoughts from this anniversary conversation. We are thrilled to continue this journey into the heart of HPI. 🏎️💨 Interviewer: ACE HPI’s passionate test pilot and mood maker! A cool red-and-black robot whose catchphrase is, "With this part, you can push even harder!" A drift master behind the wheel of an S15 Silvia, he loves racing and spirited driving more than anything. At event venues, he is the true ace of HPI, talking about our "passion for driving" more fervently than anyone else. ACE Digs Deep: The Roots of President Ryusaku Hitomi x ACE: A Special Talk (Ⅱ) ACE: President, I was absolutely blown away by your journey from your boyhood days to your first encounter with racing last time. But what specific event determined your path as a developer? You mentioned that meeting the people at Fukagawa Internal Combustion Engine changed your destiny. Hitomi: That’s right. I was so eager to work on engines that I started helping out at their factory. Their main products were exhaust headers for Nissan’s L-type engines, but they were swamped with orders and couldn't keep up with production. I started helping with the welding, even though I didn't have a license or any professional training. But as I helped, I realized, "Maybe I could do automotive work while still racing," so I started my own factory to build parts. I eventually left that company due to some minor circumstances, but my desire to race never changed, so I founded a new company. ACE: Was that TRUST (GReddy)? That was undoubtedly a golden era in your history, wasn't it? Hitomi: Yes, that was the beginning of TRUST (GReddy). I started manufacturing and selling mufflers and headers with Mr. Hayakawa. But we really had no money. We managed to borrow some land from an acquaintance in real estate, but it was just an exposed dirt floor without even electricity. We had no choice but to build mufflers and headers using gas welders and engine-driven welders. I remember working until 2:00 AM every night. ACE: On a dirt floor with no electricity, working until the dead of night… That’s a harsh environment unimaginable in today’s HPI manufacturing facilities. But President, you then faced a major crossroads: "Do I choose stability as a corporate employee, or do I keep chasing the dream of a racer?" Hitomi: Exactly. Thanks to everyone’s support, TRUST (GReddy) grew into a large corporation. But even as the business went smoothly, I always kept asking myself, "Why did I start this company in the first place?" I worked so hard because I wanted to race, but I was so busy I couldn't. Yet, I had to manage the company properly. In those days, I sacrificed sleep just to race. Furthermore, when developing parts like air cleaners, mufflers, and exhaust manifolds, I took them to the circuit myself as a test driver and drove until I was satisfied. I didn't want to rely on armchair theories; I wanted to feed all my experiences as a driver back into development. After that, I drove machines in the TRUST (GReddy) colors, competing in Freshman races with the KP61 Starlet. I participated in every category, including TS, NP, and N2. I also drove the AE86/92 and TA63/ST162 Celica, competing in domestic endurance races and Group A. In the US, I drove an IMSA GTU-spec Celica tuned by the legendary "All American Racers (AAR)," led by Dan Gurney, racing at iconic circuits like Road Atlanta and Laguna Seca. I even stood on the podium in other overseas races. Some of those overseas tracks had road surfaces and grandstands that barely felt like circuits at all! Actually, I’ve been so busy that I never had time to look back, and I didn't keep any of my trophies. Looking back now, maybe I should have kept a few 😅. ACE: If you have time to display trophies, you should be thinking about the next setting. That kind of focus is the mark of a true craftsman. Especially that legendary death match during the 1985 C/SGC race against the legendary driver Keiichi Suzuki in the Enkei Corolla— a battle for the series championship that went down to the final round. That fierce driving is still a subject of conversation today, and you were undoubtedly one of the protagonists in the most exciting era of Japanese motorsports. For over a decade, you conquered every category from endurance to sprint. And after retiring as a racer, you challenged the pinnacle of the world: the 24 Hours of Le Mans. Hitomi: That's right. After I retired, when TRUST (GReddy) challenged Le Mans, I served as the team director. At the time, we imported a Porsche Group C car into Japan for the first time, spending hundreds of millions of yen. ACE: Spending hundreds of millions of yen to import a Porsche C-car back then... It's shocking even today, but the resolve you showed in making that decision makes you a true "gambler" in the best sense of the word! But President, knowing the pinnacle of Le Mans, where the world's latest technologies compete and massive budgets are spent, why did you decide to leave that behind and start HPI from scratch? The story of Ryusaku Hitomi x ACE: A Special Talk (II) tells us that this move wasn't just a change in career, but a pursuit of your true passion. What was your core motivation when you decided to start from scratch? Hitomi: Well, I simply wanted to make parts that could actually run. I became independent from TRUST in 1998. "Parts that can run" means parts that don't just look cool, but actually increase performance— and it's even better if they are affordable. To achieve that, I incorporated new ideas in every aspect, from materials to manufacturing methods. I just wanted to satisfy the users. Our goal is to provide high-quality products at an affordable price. ✨ ACE: Because you are a passionate racer who staked everything on driving, you understand the feelings of users in the same position all too well. "Increased performance, yet accessible." It is the ultimate user perspective, one that only someone who knows the glory of Le Mans and the harsh reality of welding on a dirt floor could reach. I truly felt the soul of HPI today. Thank you for this wonderful conversation! Hitomi: Thank you, it was an interesting project. Finally, HPI exhibits at events both in Japan and abroad, so please feel free to talk to our staff at the venue. Your feedback is a hint for new product development. Of course, comments via the inquiry form on our official website or on social media are also very welcome. 🤝 ACE: Everyone, HPI will continue to drive forward with our "passion for driving" ❤️‍🔥. We will keep coming up with exciting new plans for you all, so please stay tuned! 🏎️🔥 A BIG THANK YOU to everyone who shared our previous article on social media. Your engagement and support mean the world to us and keep our passion for motorsports alive. We hope you enjoy the conclusion of Ryusaku Hitomi x ACE: A Special Talk as much as we enjoyed creating it. A heartfelt thank you to all our fans for your constant support, your visits to this English site, and for sharing our HPI Journal on social media. We will continue working hard to make this site even better for all of you. 💪 We are also truly grateful for the incredible support and frequent visits from our fans in Japan. Best regards from the HPI English site editor 🏁 This concludes our series, Ryusaku Hitomi x ACE: A Special Talk. (Note: The driving experiences described in this article reflect the traffic environment and social context of that era. It should not be interpreted as acceptable under modern traffic laws or safety standards. HPI prioritizes strict adherence to traffic regulations and promotes only safe and legal motorsports activities.)