Fidanza Aluminum Flywheel for Honda/Acura B16/B17/B18/B20

Fidanza Aluminum Flywheel - B Series

The stock B series flywheel weighs 18 pounds of cast iron and every ounce of that weight's working against you. That's a massive amount of rotational mass for an engine that makes all its power above 5,000 RPM. Fidanza's aluminum flywheel drops that weight to 7.5 pounds, that's 58% lighter than stock. The difference is huge. Your motor revs up instantly instead of winding up like it's got a boat anchor bolted to the crank. If you've been chasing throttle response on your Integra, Civic Si, Del Sol VTEC, or CR-V, this is one of the biggest improvements you're going to feel from a single part. Your engine snaps to redline, it drops RPM the second you lift off the throttle, and rev-matching downshifts becomes effortless because the motor reacts instantly to throttle blips.

Here's How Fidanza Built This Thing

Fidanza machines this flywheel from 6061 T6 billet aluminum. They're keeping the mass at the center hub where you need strength and they're removing material from the outer diameter where rotational inertia matters most. Less mass spinning at the outside edge means the engine accelerates and decelerates faster. The friction surface isn't aluminum, it's a separate 1050 high carbon steel plate that's bolted on with 16 to 20 hardened aircraft-grade fasteners and self-locking nuts. That steel friction plate doesn't warp under heat like an all-aluminum surface would. The ring gear's also 1050 steel, heat-treated and pressed on with grade 8 button screws so it's not going anywhere.

The Friction Plate's Replaceable

Here's what makes this flywheel different from most lightweight flywheels. The steel friction surface is replaceable. When you eventually do a clutch job and your friction surface is worn or scored, you're not buying a whole new flywheel or paying a machine shop to resurface it. You unbolt the old steel plate, bolt on a new one (Fidanza part number 228751), and you're done. The flywheel body's essentially a lifetime part. That replaceable friction plate saves you money in the long run because you're not replacing the entire flywheel every time you do a clutch.

Works with Any Clutch

Fidanza uses a stepped dowel system for pressure plate alignment. Once you bolt the pressure plate down, the dowels lock in place and they can't back out. The flywheel works with any clutch disc material, organic, kevlar, ceramic, metallic, sintered iron - so you're not locked into a specific clutch brand or setup. Run whatever clutch you want. The steel friction surface handles all of them.

What You're Getting Into

At 7.5 pounds, this flywheel's 58% lighter than your 18-pound stock flywheel. You're going to feel the difference the second you drive the car. The engine revs up way faster, it drops RPM way faster when you lift, and throttle response is instant. Rev-matching downshifts becomes stupid easy because the engine reacts to throttle blips immediately. On B series motors where all the power lives above VTEC crossover, that quick RPM response makes the car feel way more alive. You're not waiting for the motor to wind up anymore.

Here's the Trade-Off

RPMs drop faster between shifts. That means you need to shift quicker if you want to stay in your powerband. On a B series with VTEC engaging around 5,200 to 5,800 RPM, a slow shift can drop you below VTEC crossover and leave you in the gutless part of the rev range where the motor makes no power. Most people adapt within a day or two but it's something you need to know going in. You're also going to hear more gear chatter at idle. It sounds like the motor's got mild cams. That's normal - it's not a sign anything's wrong. The lighter flywheel just lets you hear the transmission gears a bit more.

Installation Notes

Fidanza ships this flywheel with a green protective coating on the friction surface. You need to remove that coating completely before you install the flywheel. Use acetone or lacquer thinner to clean it off. If you bolt it up with the coating still on, you're going to get clutch chatter and slipping. After you've installed the flywheel, follow Fidanza's 500-mile break-in procedure. Don't beat on it right away.

Replace Your Clutch at the Same Time

This is just the flywheel. You're already pulling the transmission to install it so if your clutch disc, pressure plate, throw-out bearing, or pilot bushing have any miles on them, replace them now. Doing the flywheel swap now and the clutch six months later means you're paying for the same labor twice. Get it all done at once.

What You Get

• Fidanza aluminum flywheel for B series engines
• Weight: 7.5 lbs (58% lighter than stock 18 lb flywheel)
• 6061 T6 billet aluminum body
• 1050 high carbon steel friction plate (replaceable)
• 1050 steel ring gear (heat-treated)
• Hardened aircraft-quality fasteners with self-locking nuts
• Stepped dowel system for pressure plate alignment
• SFI approved
• Made in USA
• Works with all clutch disc materials (organic, kevlar, ceramic, metallic, sintered iron)
• Replacement friction plate available (Fidanza part number 228751)
• 500-mile break-in period required

Fits Your Motor

• 1990-2001 Acura Integra (B17A1, B18B1, B18C1, B18C5)
• 1999-2000 Honda Civic Si (B16A2)
• 1994-1997 Honda Del Sol VTEC (B16A3)
• 1997-2001 Honda CR-V (B20B4, B20Z2)

Note: Fits all B series DOHC applications that use the standard B series transmission bolt pattern. If you're running a B series swap in an EG, EK, or other chassis, the flywheel matches to the engine and transmission - not the car. Remove the green protective coating from the friction surface completely before installation using acetone or lacquer thinner. If you don't remove it, you'll get clutch chatter and slipping. Follow Fidanza's 500-mile break-in procedure after installation - don't beat on the car right away. While you're installing the flywheel, replace your clutch components if they have any wear on them. You're already in there so do it all at once. If you're building a dedicated drag car, consider whether 7.5 lbs is the right weight for your setup. Some drag builders prefer a heavier 12+ lb chromoly flywheel because the extra inertia helps maintain RPM through shifts and makes launches more consistent. For autocross, road racing, time attack, and spirited street driving, the 7.5 lb Fidanza's the sweet spot.