Fidanza 8 lb Flywheel for RSX/EP3/06-11 Civic Si

Fidanza 8lb Aluminum Flywheel - K20/K24 RSX/Civic Si/CSX

You're building your K series and you want a lightweight flywheel that revs faster and doesn't kill your idle quality or make the car annoying to drive on the street. The stock flywheel weighs around 18-20 lbs depending on which K series you've got. Fidanza's aluminum flywheel weighs 8 lbs. That's cutting more than half the weight off the rotating assembly. You're freeing up horsepower that was being wasted spinning a heavy flywheel and you're getting faster throttle response. The engine revs quicker. It decelerates quicker. Shifts feel more direct because there's less flywheel inertia fighting you when you're clutching in. This isn't an ultra-lightweight flywheel that makes the car idle like garbage or chatter at every stoplight. Fidanza builds these at 8 lbs because that's the sweet spot where you're getting the performance benefits without the driveability problems. The flywheel's machined from 6061 T6 aluminum with a replaceable 1050 steel friction plate. The ring gear's 1050 steel, heat-treated, and pressed on with grade 8 button screws. It works with any clutch material. Organic, Kevlar, ceramic, metallic, sintered iron. Whatever you're running, this flywheel handles it.

Here's What You're Getting Over Stock

The stock K series flywheel weighs 18-20 lbs depending on which engine you've got. It's designed for a stock car with stock power and stock driving characteristics. It's not designed for performance driving. The extra weight dampens the engine's response. When you hit the throttle, the engine has to spin up that heavy flywheel before you feel the acceleration. When you lift off, the flywheel's inertia keeps the RPMs up longer so the engine takes longer to decelerate. When you're shifting, that rotational inertia makes rev-matching harder. Fidanza's 8 lb flywheel cuts that weight by more than half. The engine revs faster when you open the throttle. It decelerates faster when you lift. Shifts are crisper because there's less mass resisting the RPM change. You're also freeing up horsepower. The power that was being used to spin the stock flywheel's mass is now going to the wheels. We're not talking about created horsepower. We're talking about recovered horsepower that was already there but being lost to parasitic drag.

Why 8 Pounds and Not Lighter

You can buy flywheels that weigh 5 or 6 lbs. They're even lighter than this one. Here's why you don't want them. Ultra-lightweight flywheels don't have enough rotational mass to smooth out the engine's power pulses at idle. The engine shakes. The idle's rough. The car chatters at stoplights. Some people run them anyway because they're chasing every last bit of response. That's fine for a dedicated track car that doesn't sit in traffic. It's terrible for a street car. Fidanza engineered this flywheel at 8 lbs because that's the weight where you're getting most of the performance benefit without destroying driveability. The engine still idles smooth. The car doesn't chatter. You can drive it in stop-and-go traffic without hating your life. You're getting 90% of the performance of an ultra-lightweight flywheel with none of the headaches. That's the trade-off and it's the right one for a street/track car.

Replaceable Friction Plate and Stepped Dowel System

The friction surface is a 1050 steel plate that's heat-treated and bolted to the aluminum body with military-spec aerospace fasteners. The plate's replaceable. If you wear it out or if you overheat it and warp it, you're not buying a whole new flywheel. You're unbolting the friction plate and replacing it. The ring gear's also 1050 steel, heat-treated, heated, and pressed on. It's secured with grade 8 button screws so it's not coming off. Fidanza uses a stepped dowel system to locate the pressure plate. The dowels step down once the pressure plate's installed so they can't be removed. They're locked in place. That prevents the pressure plate from shifting or coming loose. The flywheel's machined from 6061 T6 aluminum. That's the same alloy used in aerospace applications. High tensile strength, good heat dissipation, and light weight. Fidanza doesn't just copy the stock flywheel out of aluminum like some companies do. They analyze the stock design and engineer improvements. Better balance, tighter clearances, optimized design. These flywheels are built in the USA.

What You Get

• Fidanza 8 lb aluminum flywheel for K20/K24 engines
• Weight: 8 lbs (40-60% lighter than stock 18-20 lb flywheel)
• Machined from 6061 T6 billet aluminum
• Replaceable 1050 steel friction plate (heat-treated, bolted with military-spec fasteners)
• 1050 steel ring gear (heat-treated, pressed on, secured with grade 8 button screws)
• Stepped dowel system (locks pressure plate in place, prevents shifting)
• Compatible with all clutch materials (organic, Kevlar, ceramic, metallic, sintered iron)
• Designed and manufactured in USA
• Lower moment of inertia (faster throttle response, quicker acceleration/deceleration)
• Optimized weight for street/track use (not ultra-light, maintains good idle quality)

Fits These Engines

• K20A2 - 2002-2004 Acura RSX Type-S
• K20A3 - 2002-2006 Acura RSX Base, 2002-2005 Honda Civic Si
• K20Z1 - 2005-2006 Acura RSX Type-S
• K20Z3 - 2006-2011 Honda Civic Si, 2006-2011 Acura CSX

Fits These Cars

• 2002-2006 Acura RSX Base/Type-S
• 2002-2005 Honda Civic Si
• 2006-2011 Honda Civic Si
• 2006-2011 Acura CSX

Note: Weighs 8 lbs (stock flywheel is 18-20 lbs) - 40-60% weight reduction. Optimized at 8 lbs for street/track use - lighter than stock for performance benefits but not ultra-light (5-6 lbs flywheels cause rough idle, chatter, poor driveability). Lower moment of inertia means faster throttle response, quicker engine acceleration and deceleration, crisper shifts. Frees up horsepower previously lost to spinning heavy stock flywheel (not created power - recovered parasitic loss). Replaceable friction plate - if plate wears out or warps, unbolt and replace without buying new flywheel. Stepped dowel system locks pressure plate in place and prevents shifting. Compatible with all clutch materials (organic, Kevlar, ceramic, metallic, sintered iron). 1050 steel friction plate and ring gear both heat-treated for durability. Ring gear pressed on and secured with grade 8 button screws. Military-spec aerospace fasteners attach friction plate to aluminum body. Machined from 6061 T6 billet aluminum (high tensile strength, good heat dissipation, lightweight). Designed and manufactured in USA - not a copy of stock flywheel in aluminum, Fidanza engineers improvements in balance, clearances, and design. Requires clutch replacement during installation (pull flywheel, install new clutch and flywheel together). Professional installation recommended unless experienced with clutch/flywheel jobs.