Live Stock Checker
NISMO Lightweight Flywheel Skyline
Brand: Used Parts
Product Code: nismo-12310-RSR21
Ex VAT: £0.00
Out Of Stock
Last Stock Check:
Nismo RSR21 Lightweight flywheel for RB25/26
Vehicle Model: RB20DET / RB25DET / RB26DETT
Engine Type: R32/R33
This lightweight flywheel is created especially for use with NISMO single-plate clutches. Not only is it light, it provides the ideal weight to guarantee even engine rotation in the low rpm range.
The use of high strength, high quality chrome molybdenum carbon steel reduces weight by 60% to 70% compared to standard flywheels. Used with a NISMO clutch cover and clutch disc, the package provides a total inertia weight reduction of 80% to 85%, reducing torque loss at low speed while improving response at high rpm.
When used with a solid metal disc, it provides a more direct feel than a dual-mass (damper equipped) unit. At the same time, the same ring gear chamfering process as for standard parts has been used to ensure smooth starting through improved engagement with the starter motor pinion gear.
Unit Weight kg (Genuine OEM Item): 6.88 (9.65)
Inertial Weight kg/cm/sec2 (Genuine): 1.738 (2.904)
Made Exclusively for use with NISMO Single Plate Discs
Manufactured from Chrome molybdenum SCM440H
Dowel Pin (press-in type)
Provides Ideal Weight to Guarantee Even Engine Rotation in Low
Reduced Weight by 60% to 70%
Reduced Torque Loss
Why fit a lightweight flyhweel ?
It takes a lot of inertia out of the engine and so the whole car feels noticeably more lively. Performance also improves measurably.
It doesn't change power, just inertia, but the vehicle will feel more powerful as less energy is required to overcome inertia so more can be used to accelerate the car.
It will also help reduce time to pull the engine speed down on an upshift and increase it on a downshift.
You need to make sure that the weight is reduced in a way that doesn't detract from strength, and also balance the unit afterwards, or ideally as part of a rebuild where all components are balanced as an assembly.
It might not be the best for daily road driving, as the standard OEM flywheels help smooth out car control.
If it's a pure track car, then the benefits would outweigh the disadvantages.
The main advantage to a lower flywheel mass on race cars is that the reduced mass allows the engine to rev more freely. The overall weight loss to the car is really not the key thing, it's letting the engine vary RPM really quickly.
Being able to change RPM quickly can mean faster shifts, getting to a power band more quickly, etc, etc. It also makes the car much more twitchy to drive since it doesn't like low RPM very much. At low RPM the lower mass of the flywheel means you need to use the throttle to keep the RPM above where the flywheel isn't going to carry things around as well. For a race car that's not a big deal. For the family driver with the manual transmission, it's a big problem