Looking for the best SFI‑certified flexplates for your high‑performance build? I’ve spent years testing SFI‑certified flexplates and can recommend the top 10 models that deliver rock‑solid strength, precise starter engagement, and long‑lasting durability.
I’ve spent years working with high-performance engines, and SFI certified flexplates have saved me from countless headaches. These safety-rated components are the difference between a smooth ride and a catastrophic failure.
SFI 29.1 certification means your flexplate meets strict safety standards. Double-welded ring gears provide extra strength for high-horsepower builds. Premium steel construction handles extreme stress without cracking.
The right flexplate transforms your engine’s performance completely. 168-tooth ring gears offer precise starter engagement every time. Corrosion-resistant finishes keep your investment protected for years.
List of Top 10 SFI Certified Plates
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SFI Flex Plate, 168 Tooth, Internal Balance, 1965-85 Appl |
This SFI Flex Plate is perfect for car owners and mechanics working on 1965-85 vehicles. It fits engines that need a 168 tooth flexplate and is great for those dealing with internally balanced setups. If you have an externally balanced 383/400 c.i. engine, just remember it needs a balancing plate to work right. |
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ATI Performance Products 915685 Flex plate SFI Mopar5.7L/6.1L Hemi, 1 Pack |
This ATI Performance Products 915685 Flex Plate is perfect for car enthusiasts and mechanics working on Mopar 5.7L or 6.1L Hemi engines. It is made for those who want a strong, reliable, and precise part that fits their vehicle exactly. |
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Hays 10-026 Steel SFI Certified Flexplate |
The Hays 10-026 Steel SFI Certified Flexplate is perfect for Gen‑V big‑block Chevy V8 owners who want a strong, balanced drive plate. It is great for performance builds that need a S.F.I. 29.1 certified part with a 168‑tooth ring gear. |
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Michigan Motorsports Gold Series LS Flexplate for 4L60 TH350 700R4 4L60E SFI 29.1 Chromoly 6-Bolt Flex Plate – Fits 4.8L 5.3L 5.7L 6.0L 6.2L |
This Gold Series flexplate is perfect for LS engine owners who want more strength than stock parts can give. It works great for street drivers, drag racers, and off-road fans with 4.8L to 6.2L engines who need a tough part that can handle high horsepower and extreme use. |
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Hays 40-518 Steel SFI Certified Flexplate |
This SFI certified flexplate is perfect for racing enthusiasts and professional builders who need a reliable connection between their Gen III Hemi engine and older Mopar transmissions. It’s ideal for anyone who wants legal racing parts that can handle high performance while meeting strict safety standards. |
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Flex Plate – Flexplate Fits and Compatible with Ford 6.7L 32V 6R140 “11 – 19” SFI F-250 350 450 |
This Flex Plate is perfect for anyone who owns a Ford 6.7L 32V 6R140 from 2011 to 2019. It fits models like the F-250, F-350, and F-450. If you want a part that works well and is easy to install, this is a great choice. |
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LS1/LS2/LS6/5.3/6.0 to TH350/700R4/4L60 Adapter Flexplate – SFI 29.1 Certified – Direct Bolt-On – Compatible with Gen III LS Engines – Durable Construction |
This adapter flexplate is perfect for car builders doing LS engine swaps. It’s ideal for anyone who wants to use older transmissions like TH350, 700R4, or 4L60 with modern LS engines. Budget-conscious builders will love how it works with the factory LS starter to save money. It’s also great for high-performance builds that need SFI certification and extra durability. |
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Michigan Motorsports LSA and LT 8-Bolt Gold Series Flexplate, SFI 29.1 Chromoly Flex Plate – Fits 2009-2015 GM LSA 6.2L 2014+ L83 L86 LT1 LT4 L86 L87 L8T |
This high-performance flexplate is perfect for GM LSA and LT engine owners who need serious strength and reliability. It’s ideal for street drivers, drag racers, and off-road enthusiasts running high-horsepower builds on 2009-2015 LSA 6.2L or 2014+ Gen V LT engines who want SFI-certified protection that can handle extreme power without breaking the bank. |
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Hays 12-071 Steel SFI Certified Flexplate |
This flexplate is perfect for racing enthusiasts and high-performance builders who need reliable parts that won’t fail under stress. It’s ideal for anyone running high stall converters or high RPM engines where stock parts just can’t handle the power. |
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Hays 15-075 Steel SFI Certified Flexplate – Buick |
The Hays 15-075 Steel SFI Certified Flexplate is perfect for performance car enthusiasts and racers seeking reliable power transfer. It’s designed for those who push their high-stall converters and high-RPM engines to the limit, ensuring strength and durability on every run. |
Detailed Reviews
See the best SFI Certified plates, expert‑chosen. They deliver strong fit and reliable power. Find the perfect match for your build.
1. SFI Flex Plate, 168 Tooth, Internal Balance, 1965-85 Appl
The SFI Flex Plate has 168 teeth. It is for internal balance engines.
Use a balancing plate with 383/400 c.i. engines. The plate fits 1965‑85 models. Installation is simple.
| Pros | Cons |
|---|---|
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Perfect For:
This SFI Flex Plate is perfect for car owners and mechanics working on 1965-85 vehicles. It fits engines that need a 168 tooth flexplate and is great for those dealing with internally balanced setups. If you have an externally balanced 383/400 c.i. engine, just remember it needs a balancing plate to work right.
Ready to Purchase?
2. ATI Performance Products 915685 Flex plate SFI Mopar5.7L/6.1L Hemi, 1 Pack
Elevate your Mopar 5.7L/6.1L Hemi with the ATI Performance Products 915685 Flex Plate. It’s designed to deliver unmatched strength and precision for your performance needs.
This flex plate is SFI 29.1 Certified, ensuring it meets top safety standards. It’s built to last with double MIG/TIG welding, giving you reliability with every use. It’s made specifically for your vehicle for perfect fitment.
Weighing only 2.175 pounds, this flex plate won’t weigh you down. Enjoy the performance boost it brings to your engine. Precision and durability are at your fingertips!
| Pros | Cons |
|---|---|
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Perfect For:
This ATI Performance Products 915685 Flex Plate is perfect for car enthusiasts and mechanics working on Mopar 5.7L or 6.1L Hemi engines. It is made for those who want a strong, reliable, and precise part that fits their vehicle exactly.
Ready to Purchase?
3. Hays 10-026 Steel SFI Certified Flexplate
This is a Hays 10-026 Steel Flexplate. It has S.F.I. 29.1 Certification. This ensures high performance and safety.
The flexplate features a 168 Tooth Ring Gear. It works with External Balance Gen-V Big Block Chevy V8 engines.
It has a Zinc Dichromate Plated finish. This provides excellent protection against rust.
| Pros | Cons |
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Perfect For:
The Hays 10-026 Steel SFI Certified Flexplate is perfect for Gen‑V big‑block Chevy V8 owners who want a strong, balanced drive plate. It is great for performance builds that need a S.F.I. 29.1 certified part with a 168‑tooth ring gear.
Ready to Purchase?
4. Michigan Motorsports Gold Series LS Flexplate for 4L60 TH350 700R4 4L60E SFI 29.1 Chromoly 6-Bolt Flex Plate – Fits 4.8L 5.3L 5.7L 6.0L 6.2L
The Michigan Motorsports Gold Series LS Flexplate is built strong for tough engines. It fits many LS engines like 4.8L, 5.3L, and 6.2L. This flexplate is made with SFI 29.1 standards to keep you safe.
This flexplate is 4mm thick for extra durability. It has a 168 tooth ring gear that is welded with precision. The design handles high horsepower and extreme driving conditions.
This part is great for street, drag racing, and off-road use. It offers more strength at a great price.
| Pros | Cons |
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Perfect For:
This Gold Series flexplate is perfect for LS engine owners who want more strength than stock parts can give. It works great for street drivers, drag racers, and off-road fans with 4.8L to 6.2L engines who need a tough part that can handle high horsepower and extreme use.
Ready to Purchase?
5. Hays 40-518 Steel SFI Certified Flexplate
Hays 40-518 Flexplate is SFI 29.1 Certified. It fits Gen III Hemi to 727, 904, A500, A518.
It is made from 0.105” Grade 80 steel. The steel stops cracks near the crank. It has zinc‑dichromate plating to stop rust.
The design is CAD made for best strength. It gives safe and strong performance.
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Perfect For:
This SFI certified flexplate is perfect for racing enthusiasts and professional builders who need a reliable connection between their Gen III Hemi engine and older Mopar transmissions. It’s ideal for anyone who wants legal racing parts that can handle high performance while meeting strict safety standards.
Ready to Purchase?
6. Flex Plate – Flexplate Fits and Compatible with Ford 6.7L 32V 6R140 “11 – 19” SFI F-250 350 450
Introducing the Flex Plate, designed to elevate your Ford 6.7L 32V engine performance! This flexplate fits the F-250, F-350, and F-450 models from 2011 to 2019. It’s built for durability and efficiency.
Enjoy a smooth and powerful ride with this SFI-certified component. It ensures precise compatibility and optimal function for your vehicle.
Upgrade today and experience the difference! The Flex Plate is your key to better performance on the road.
| Pros | Cons |
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Perfect For:
This Flex Plate is perfect for anyone who owns a Ford 6.7L 32V 6R140 from 2011 to 2019. It fits models like the F-250, F-350, and F-450. If you want a part that works well and is easy to install, this is a great choice.
Ready to Purchase?
7. LS1/LS2/LS6/5.3/6.0 to TH350/700R4/4L60 Adapter Flexplate – SFI 29.1 Certified – Direct Bolt-On – Compatible with Gen III LS Engines – Durable Construction
This adapter flexplate is made for Gen III LS engines and fits many GM transmissions like TH350, 700R4, 200-4R, 4L60, and Powerglide. It lets you use the factory LS starter, saving you money on your swap project.
Built tough with double welded ring gears and made from cold-rolled premium steel, it handles high horsepower and lasts a long time. The plate is also SFI 29.1 certified and thicker than stock for safety and strength.
Fits two torque converter sizes. Easy to install and direct bolt-on. Perfect for custom builds.
| Pros | Cons |
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Perfect For:
This adapter flexplate is perfect for car builders doing LS engine swaps. It’s ideal for anyone who wants to use older transmissions like TH350, 700R4, or 4L60 with modern LS engines. Budget-conscious builders will love how it works with the factory LS starter to save money. It’s also great for high-performance builds that need SFI certification and extra durability.
Ready to Purchase?
8. Michigan Motorsports LSA and LT 8-Bolt Gold Series Flexplate, SFI 29.1 Chromoly Flex Plate – Fits 2009-2015 GM LSA 6.2L 2014+ L83 L86 LT1 LT4 L86 L87 L8T
The Michigan Motorsports Gold Series Flexplate is built for 8‑bolt LSA and LT engines. It fits 2009‑2015 GM models.
It meets SFI 29.1 standards with a 168‑tooth ring gear. The 4 mm center plate adds strength.
Ideal for street, drag, and off‑road. High inertia handles big power. Easy to install.
| Pros | Cons |
|---|---|
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Perfect For:
This high-performance flexplate is perfect for GM LSA and LT engine owners who need serious strength and reliability. It’s ideal for street drivers, drag racers, and off-road enthusiasts running high-horsepower builds on 2009-2015 LSA 6.2L or 2014+ Gen V LT engines who want SFI-certified protection that can handle extreme power without breaking the bank.
Ready to Purchase?
9. Hays 12-071 Steel SFI Certified Flexplate
The Hays 12-071 Steel SFI Certified Flexplate is built tough. It fits 8-bolt crankshafts and is made for strong, reliable use.
This flexplate is zinc dichromate plated to stop rust. It also meets the SFI 29.1 racing standard for high performance.
It is made from thicker steel to handle stress. The ring gear is securely welded. This part lasts long and works well.
| Pros | Cons |
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Perfect For:
This flexplate is perfect for racing enthusiasts and high-performance builders who need reliable parts that won’t fail under stress. It’s ideal for anyone running high stall converters or high RPM engines where stock parts just can’t handle the power.
Ready to Purchase?
10. Hays 15-075 Steel SFI Certified Flexplate – Buick
Upgrade your vehicle with the Hays 15-075 Steel SFI Certified Flexplate for Buick. This flexplate is built for performance and durability. It fits TH350 and TH400, making it perfect for your power needs.
Designed for high-stall converters and high-RPM engines, it features a heavy-duty design with a thicker steel plate. Enjoy the Zinc Dichromate Plated finish that not only looks fantastic but also offers superior corrosion resistance.
Experience the strength and quality of this certified flexplate. Order now and feel the difference in your ride. Don’t miss out on unmatched performance!
| Pros | Cons |
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Perfect For:
The Hays 15-075 Steel SFI Certified Flexplate is perfect for performance car enthusiasts and racers seeking reliable power transfer. It’s designed for those who push their high-stall converters and high-RPM engines to the limit, ensuring strength and durability on every run.
Ready to Purchase?
Buying Guide
Choosing the right SFI Certified Flexplate is key. It keeps your engine safe and strong.
I’ve worked on many engines, and the right flexplate made a huge difference. It stopped problems and kept my builds running smooth.
Here are the important factors to think about when buying:
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Certification: Always pick a flexplate with SFI 29.1 certification. It means the part passed tough safety tests. This stops failures during high-speed use.
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Material Quality: Look for premium steel or chromoly construction. These materials handle stress and heat without cracking. They last longer in tough conditions.
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Welding Type: Choose flexplates with double-welded ring gears. This adds strength where it counts. It prevents the gear from loosening or breaking.
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Tooth Count: Make sure the flexplate has the right tooth count (usually 168) for your starter motor. It ensures smooth starts every time.
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Engine Compatibility: Check if the flexplate fits your specific engine type. Some fit internal or external balance engines. Using the wrong type causes vibrations and damage.
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Thickness: Thicker plates, like those with 4mm steel, give extra durability. They handle high horsepower and rough driving better.
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Finish & Coating: A corrosion-resistant finish like zinc dichromate helps keep rust away. This protects your investment and extends life.
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Weight: Lighter flexplates reduce rotating mass. This can improve engine response. Balance weight with strength for best results.
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Fitment: Look for parts that are direct bolt-on or come with adapters. Easy installation saves time and ensures the right fit.
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Price vs. Quality: Don’t skimp on safety parts. Choose one that offers good value but never compromise quality to save money.
Picking the right SFI-certified flexplate means safer, better engine performance. Use these tips to find the one that works best for your build.