The highest published figure in this group belongs to modern nitro HEMI-based drag-racing engines: the NHRA described them at 12,000 hp in 2025. Below them are specialist crate and race engines, led by a 1,500-hp Direct Connection HEMI announced in 2022. The production-car story is different: the classic 426 Street HEMI was marketed at 425 gross hp, while modern supercharged crate engines such as the Hellephant are rated far higher.
Those numbers are not a single apples-to-apples test. They span race-engine estimates, preliminary crate-engine estimates, current catalog ratings, and historical gross and net ratings. The rankings below keep those categories distinct and identify the source and context for each figure.
How to read the HEMI horsepower rankings
“HEMI” covers more than one engine and use case. This selection includes Chrysler production-car engines, manufacturer-backed crate engines, and specialized competition derivatives built around HEMI architecture. A purpose-built nitro engine is not a stock 426, and a crate engine’s advertised output should not be treated as directly comparable with an old gross or net rating.
The figures are ranked within those limits, using published output rather than a common test protocol. Sources do not provide a complete, consistently measured catalog of every HEMI variant, so this is a selection of important examples—not a technical inventory of every engine ever built.
#1 Best Overall
- 【Authentic V8 Engine Replica】This highly detailed model kit accurately reproduces a classic 8-cylinder engine, complete with moving pistons, a working valve train, a turbocharger, and an exhaust system. It dynamically reveals the intricate internal mechanics and fundamental principles of a real internal combustion engine, making it a centerpiece for any mechanical enthusiast or model collector
- 【Battery-Free Realistic Motion】Powered by a two-speed USB rechargeable motor, this V8 model simulates genuine engine operation without the need for batteries. Watch the engine fan spin and the pistons move in rhythmic motion, delivering an eco-friendly and captivating immersive experience for every car lover
- 【STEM Learning Adventure】An ideal educational toy for ages 14 and up, this V8 engine enhances creativity, strengthens hands-on abilities, and develops problem-solving skills through assembly and adjustment. Perfect for STEM classrooms, tech clubs, or as an engaging family project that makes learning fun
- 【Premium & Durable Construction】Crafted from high-quality materials, the BseSparklion V8 model consists of 1176 precision pieces. Designed for seamless assembly, it provides a satisfying and rewarding building process while ensuring the finished model is sturdy and long-lasting, reflecting true automotive excellence
- 【Ideal Gift for Car Mechanic Enthusiasts】The ideal gifts for any occasion, this V8 engine model is a must-have for car fanatics, model builders, and admirers of fine craftsmanship. It serves as a striking conversation piece that proudly showcases a passion for mechanical engineering
Which HEMI engine made the most horsepower?
By the highest published figure in the sources cited here, modern nitro HEMI-based engines used in Top Fuel dragsters and nitro Funny Cars lead. NHRA described them at 12,000 hp in 2025. That is a description of highly specialized competition engines, not a factory rating for a street HEMI.
| Rank by published figure | Engine or application | Published output | What the figure represents |
|---|---|---|---|
| 1 | Modern nitro HEMI-based Top Fuel and Funny Car engines | 12,000 hp | NHRA’s 2025 description of billet-aluminum, nitromethane-burning competition engines. |
| 2 | Nitro-fueled Gen II HEMI-based Top Fuel and Funny Car engines | 11,000+ hp | Stellantis North America’s 2019 history figure; a separate source and year from NHRA’s later 12,000-hp description. |
| 3 | Funny Car HEMI-based engine | Approximately 8,000 hp | Stellantis North America’s 2014 estimate. It reflects a different date and engine context, not a figure to average with the later descriptions. |
These engines are specialized descendants of HEMI architecture, not stock 426 engines. The change in published estimates across sources and years is a reason to preserve their attribution rather than present one timeless, exact output.
Rank #2
- Unleash the power of engineering with the Nifeliz V8 Engine model. This detailed assembly replicates the intricate design of a real V8 engine, providing a thrilling challenge for mechanical enthusiasts.
- Experience the precision of real engineering. The pistons and valves move in sync, giving you a firsthand view of how a V8 engine works—ideal for those who love mechanical details.
- Feel the excitement as the central fan rotates in harmony with the engine, simulating a turbocharged effect and adding an extra layer of realism to your build.
- More than a model, this V8 engine replica doubles as a striking display piece. It’s a chance to learn the inner workings of an engine while appreciating the beauty of mechanical design.
- This meaningful building toy is the ideal gift for mechanical enthusiasts, offering both a hands-on learning experience and a unique display for any home or office.
Which HEMI crate and specialist race engines rank highest?
The next group includes a specialist 1,500-hp engine announced for racing use and modern crate engines intended for builders. Their published ratings are not equivalent: one comes from a manufacturer announcement, some were explicitly preliminary estimates, and others are current catalog figures.
| Rank by published figure | Engine | Published output | Configuration and rating context |
|---|---|---|---|
| 1 | Direct Connection 1500 HEMI crate engine | 1,500 hp; 1,000 lb-ft | Stellantis North America announced this engine in 2022, identifying DSR Performance as the offeror. The announcement does not establish current availability. |
| 2 | Direct Connection Hellephant A170 | Above 1,100 hp | 2022 preliminary estimate on E85, announced by Stellantis North America. |
| 3 | Direct Connection Hellephant A30 | 1,000 hp | 2022 preliminary estimate on premium fuel, announced by Stellantis North America. |
| 4 | Direct Connection Hellephant C170 | Above 1,000 hp | 2022 preliminary estimate on E85, announced by Stellantis North America. |
| 5 | Mopar Hellephant 426 Supercharged HEMI | 1,000 hp; 950 lb-ft | Mopar’s current product catalog, accessed in 2026. A supercharged crate engine, distinct from the naturally aspirated 1960s 426 Street HEMI. |
| 6 | Direct Connection Hellephant C30 | Approximately 900 hp | 2022 preliminary estimate on premium fuel, announced by Stellantis North America. |
| 7 | Mopar Hellcrate Redeye 6.2L | 807 hp; 717 lb-ft | Mopar current catalog, accessed in 2026. |
| 8 | Mopar 6.2L Supercharged Crate HEMI | 707 hp; 650 lb-ft | Mopar current catalog, accessed in 2026. |
| 9 | Mopar SRT 6.4L HEMI | 485 hp; 475 lb-ft | Mopar current catalog, accessed in 2026. |
Direct Connection 1500 HEMI
The largest figure in this crate and specialist-race group is 1,500 hp, with 1,000 lb-ft of torque. Stellantis North America’s 2022 announcement said DSR Performance offered the engine. That announcement documents the rating and offer at that time; it does not confirm that the engine can still be ordered.
What’s actually slowing this PC down?
Pick the symptom - the matching free tool is one click away.
Rank #3
- GET HANDS ON with Playz V8 engine model kit that works for adults and kids alike. Engage young minds into STEM with a working replica of a classic 8-cylinder internal combustion car engine, while adults enjoy the rewarding experience of building their own mini V8 engine kit that runs like a dream.
- REALISTIC MODEL THAT WORKS: Deliver the action of a classic car engine with powerful pistons and interactive cables! Watch the motor fans turn on with real engine sounds from your visible V8 engine model kit, making it a perfect STEM toy for curious minds seeking a fun blend of education and entertainment.
- FUEL THE FUN: Our complete toy V8 engine assembly kit provides hours of fun as you tinker with cranks, pulleys, belts, and exhaust valves, bringing this miniature engine kit to life before your very eyes! Conquer long boring days with a small V8 engine kit that runs. (Requires 3x AA Batteries not included)
- CHALLENGE ACCEPTED: Supercharge your critical thinking skills with our mini engine build kit! Expand your creativity, think logically, and refine your motor skills as you build a model V8 engine kit all while having fun. Get ready for a brain-boosting build challenge that works wonders!
- POPULAR GIFT THAT INSPIRES: Make the world of STEM amazing with our DIY engine kits for adults, teens, young boys and girls! Whether it's for birthdays, holidays, or any special occasion, Playz V8 model engine kit will keep them captivated as they build and operate their own engine from start to finish.
Direct Connection Hellephant A and C engines
Stellantis North America’s 2022 announcement gave preliminary estimates for four variants. The A170 was estimated above 1,100 hp on E85, and the C170 above 1,000 hp on E85. On premium fuel, the A30 was estimated at 1,000 hp and the C30 at approximately 900 hp. These were preliminary estimates, not independently verified test results. Their ordering by stated output should not be mistaken for a controlled comparison.
Mopar catalog crate engines
Mopar’s catalog, accessed in 2026, lists the supercharged Hellephant 426 at 1,000 hp and 950 lb-ft. It also lists the Hellcrate Redeye 6.2L at 807 hp and 717 lb-ft, the 6.2L Supercharged Crate HEMI at 707 hp and 650 lb-ft, and the SRT 6.4L HEMI at 485 hp and 475 lb-ft. These are current catalog ratings, not the output of the historic street engines that share HEMI family names or displacement references.
Rank #4
- 【V8 Engine Building Kit】Accelerates from standstill to 100 km/h in just 3 seconds. Its unique turbocharged design optimizes responsiveness and virtually eliminates turbo lag, ensuring quick and smooth power delivery at all speeds.
- 【Transparent Cylinder Head Design】This product is powered by the equipped battery and reproduces the dynamic principle 1:1 for you. Through the transparent cylinder cover, the movement of the piston can be observed. It contains many realistic details. Such as transparent cylinder head, simulate piston motion, Turbocharger.
- 【MOC V8 Engine】Mould King V8 Engine building block kits is assembled from 2718 building block parts and has colorful paper instructions to help you easily assemble it. This building block kit compatible with mainstream building blocks. All parts are easy to assemble and will not fall apart.
- 【Fun Building Challenge】Mould King V8 Engine Kits made from ABS materials and tested for quality control to ensure compliance with safety standards. MOC building blocks toys are designed to provide the interesting and challenging building experiences. The building blocks are the challenges during assembling and the achievement after finishing.
- 【Ideal Present】 Mould King building set is a good collection. It suits for adults and collectors. If you are looking for a cool present for your lover or family's birthday/ Christmas/ New Year. Or you have searched for a building block challenge, this product is the best choice!
How do the historic street HEMIs compare?
Among the historical street examples here, the 426 Street HEMI has the higher published horsepower figure. Stellantis North America gives 425 gross hp for the 426 Street HEMI and 180 hp for the first-generation FirePower HEMI, which arrived for the 1951 model year. The rating context for the 180-hp figure is not specified in the cited history, so it should not be treated as directly comparable with the 426’s stated gross figure.
| Street engine | Published output | Period and context |
|---|---|---|
| 426 Street HEMI | 425 gross hp; 350 net hp | Stellantis North America’s 2014 account gives both figures for the 1971 street version. Gross and net ratings use different conventions; neither is the 426’s race-engine output. |
| First-generation FirePower HEMI | 180 hp | Stellantis North America’s 2019 HEMI history; introduced for the 1951 model year. The cited history does not identify the rating convention. |
Why the 426 has several very different numbers
The 426 was developed for competition in the early 1960s. NHRA recounts that Chrysler engineer Bill Weertman and a small team were tasked in December 1962 with developing a 426-cubic-inch engine for the 1964 NHRA Winternationals and Daytona 500. NHRA describes Drag and Track race versions from 1964–66 alongside the Street HEMI, which appeared in production cars in 1966.
Best Value
- 【Realistic V8 Engine Model】This exquisitely designed V8 engine model features realistic details like a transparent cylinder head, simulated piston movement, and a turbocharger. Its compact design accurately mimics the inner workings of a real V8 engine, making it a unique and engaging mini engine toy
- 【USB Charging Motor Design】This V8 engine kit includes a motor (No Battery Required) and a USB charging cable, enabling the model toy to be electrically driven. You can watch the movement of the internal pistons through the transparent cylinder heads on both sides and get a sense of how the V8 engine powers the car
- 【Safe High Quality Material】This V8 engine kit is made of ABS material, non-toxic and odor-free, and is tested by ASTM and CPSIA to ensure a safe and building experience. If you have any questions, please feel free to contact us so that we can provide you with the best service
- 【STEM Educational Toys】Our MOC engine toys provide hours of building fun that will not only spark your interest in mechanics and engineering, but also help expand your creativity, logical thinking and problem solving skills. The perfect STEM project for everyone's family to build and play with teens and boys
- 【Perfect Gift for Car Fans】This V8 engine model, designed for people who like car and mechanical engineering, is suitable for adults, teens and boys 8-14+. Its practicality and collectibility make it the perfect gift for any special occasion, such as Christmas, Birthdays, STEM educational events, etc
Stellantis North America’s 2014 account places the race engines at the 1964 Daytona 500 “somewhere in the neighborhood of 750 horsepower.” That is an approximate race-output figure, not an official production rating. The street version’s 425 gross hp and 350 net hp in 1971 are separate ratings for a production engine. Combining the figures into one ranking entry would erase the distinction between race and street specifications.
What changed from the first FirePower to the 426?
The first-generation FirePower HEMI arrived for the 1951 model year with a published 180 hp in Stellantis North America’s 2019 history. More than a decade later, Chrysler adapted hemispherical combustion chambers to a deep-skirt 426-cubic-inch block for competition. NHRA quotes Chrysler engineer Tom Hoover recalling the design direction: “We suggested putting Hemi head on the wedge block,” Hoover recalled. “It wasn’t radical; it was just the best way to take advantage of work that had already been done.”
The 426 was not one fixed specification: the competition Drag and Track versions and the production Street HEMI served different purposes. Modern crate engines such as the supercharged Hellephant use the 426 name and HEMI architecture, but their advertised outputs describe modern products, not the original street engine.
What the rankings can—and cannot—tell you
- For the highest published horsepower: NHRA’s 2025 description of modern nitro HEMI-based drag-racing engines is 12,000 hp.
- For a named crate or specialist-race figure: Stellantis North America announced the Direct Connection 1500 HEMI at 1,500 hp in 2022, while its current availability is not established here.
- For a current catalog crate-engine rating: Mopar lists the Hellephant 426 at 1,000 hp in a catalog accessed in 2026.
- For a historic production-car HEMI: the 426 Street HEMI was marketed at 425 gross hp, with Stellantis also reporting 350 net hp for the 1971 street version.
Each is an answer to a different version of “most powerful”: race-engine estimate, announced crate-engine output, current catalog rating, or period street-car rating. Keeping those labels attached is more informative than treating the horsepower figures as though they came from one standardized test.
Do these 3 things before closing this tab:
1Scan for outdated or missing drivers - takes under a minute2Clear out junk files and repair common Windows errors3Fix the driver behind crashes, sound loss and screen glitchesQuick Recap
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
