Quicker throttle response and faster
acceleration at your command...
UUC's Lightweight flywheel for the
Cadillac CTS-V will give your car quicker acceleration, easier rev-matching,
and quicker shifting responsiveness.
Our SFI-certified flywheel uses standard CTS-V clutch components and requires
no modifications for installation.
lightweight flywheel works
How does a
lightweight flywheel work? Amongst the majority, there are two schools
of thought concerning light flywheels. The first is that they do not
contribute to power output. The second is that they do. Which thought is
correct? In fact both, in a way, are correct.
If we measured the power
output of an engine first with light flywheel and then again with the standard
part on an engine dyno, no change in power will be seen to occur. At first it
appears that the light flywheel has done nothing and was a total waste of
cash. This is not the case. A dyno that shows max power at constant revs does
not demonstrate what happens to an engine's power output in real life
situations - like acceleration. If an engine is accelerated on a dyno (we are
talking about a rate of around 2000rpm a second ) it would show a power output
of around 20%-25% less than at the constant rev state.
The reason for this is
that when accelerating a vehicle the engine not only has to push the total
mass of the car but the internal components of the engine need to be
accelerated also. This tends to absorb more power as the extra power is used
accelerating the internal mass of the engine components and is why a motor
accelerating on a dyno will produce less power than at constant revs. Also it
must be remembered that the rate of acceleration on the engine internals is
much greater that the rest of the car. This would then suggest that by
lightening the flywheel, less power would be required to accelerate it and
therefore more power would be available to push the car along.
Now, it may seen
unbelievable that by removing a few pounds from the flywheel a noticeable
difference to a 3000lb+ carís acceleration will be made. In fact the
difference is quite noticeable and the secret behind this is hidden within the
gearbox. Everyone knows that cars accelerate at a greater rate in low gears,
this is because a carís gear box basically a mechanical lever and just like
when using a leaver to lift a heavy object, the gearbox reduces the mass of
the car that the engine sees. For example, in first gear an engine will see
the car's mass as only around say 250lbs but the engine internal mass would
still remain around 45lbs.
for the "virtual" weight loss of a typical lightweight flywheel in
the 3-series or M3, we've prepared the full mathematical analysis:
Calculations for UUC
flywheels showing exact "virtual" weight loss in each gear - click
here to download Acrobat .pdf fileIt
is now easier to see were the extra performance comes from when you lighten a
flywheel. You effectively "lighten" a car by more than 10% in
first gear just by removing mass from the flywheel. As the gear used increases
this "lightening" effect is reduced. This is why carís
acceleration improvement reduces in higher gears, to very effect in top gear.
Great for drags and tight race tracks but will not increase a car's top speed.
You will see the calculations include the diameter of the flywheel, weight
lost (same overall rotating mass difference in UUC Stage1 or Stage2 due to
pressure plate weight differences), gear ratios including 6-speed application,
and typical diff ratio.
The effective "virtual" weight losses are:
A general rule of thumb for weight loss equivalence to "gained"
power is approximately 10lbs/hp. That is for every 10lbs lost, the car gains
the effective performance increase of 1hp.
With that in mind, the effective performance increase expressed in gained
power can be expected to be the same as the "virtual" weight lost
due to the flywheel in each gear divided by 10:
This gear-dependent gain is also another reason why a typical 4th-gear dyno
pull may not show a significant difference - the calculations show that little
more than 4hp would be detected, yet a 4th-gear dyno run shows nothing of
real-world acceleration through the gears. Improvements in
rev-matching and upgraded clutch clamping power remain regardless of gear.Due to the nature of the "virtual" weight loss, typical 4th-gear
dyno runs may show miniscule differences. Real-world acceleration runs
will show improvement equivalent to the "virtual" weight loss.