DYNO: Fidanza Lightweight Flywheel
- Thread starter Equinox
- Start date
Little Beavis
Member
- :
- 2001 MP3-T (#911)
No dyno info in 1 or 2 then?
I'm really curious about the flywheel mod. . .need to do a clutch (and flywheel) soon. So, was it worth it?
I'm really curious about the flywheel mod. . .need to do a clutch (and flywheel) soon. So, was it worth it?
- :
- 09 370Z Nismo
very much so worth the mod, makes the car not lame. I actualy contend with other cars, because I got rid of the dreaded family car clutch. I'm not afraid to race anyone anymore, cause I rarely lose. But anyhow, the problem I got now is, when I feather/dump the clutch from a race start, my shifter linkage will sometimes come out of it's rubber mounting point just behind the cat under the car. It makes it a little harder to shift when the linkage is 3 inches lower, I unbolted the linkage at the kartboy bushing and fed it back through the mount, but it came un done again at another race, I still won tho....
Just to clarify the above statement. Think of the flywheel as just a spinning mass. You go through the gears much faster in first and second than in the other higher gears. So...lets implement a classic physics equation Force=Mass*Acceleration. Take force to be the horsepower required to accellerate the flywheel. What happens when you decrease the mass by 1/2 which is what you essentially do with the fidanza. You get 1/2 the force required because Acceleration stays the same. That decrease in force required to accelerate the flywheel goes to the wheels instead. This is of course only under acceleration because force is only applied during any change in velocity(or in other words an accelleration or a decelleration)
God I'm such a nerd....
God I'm such a nerd....
melicha8 said:
You're working in the right direction, but it's actually a bit more complicated (and worse) than that. This is a spinning mass, which makes it a non-linear relationship (you can't just say half the mass is twice as good), but even worse when you have more mass. It's the same reason why an additional couple of pounds on your wheels takes quite a bit more away from performance than just putting some extra weight in your trunk, for example.
Patrick
Little Beavis
Member
- :
- 2001 MP3-T (#911)
Ah yes, but since we're all being nerds, it would be more important to understand the moment of inertia of the flywheel. You could create a lighter flywheel but by nature of the location of the mass create one that has the same moment of inertia as a heavier one. . .and well. . .damn, I need to drink less. . .I'm going to bed. Sorry.
But I'm still curious as to whether it really makes that big of a difference or not, but everyone says it does. . .so I have NO idea why I keep asking!
But I'm still curious as to whether it really makes that big of a difference or not, but everyone says it does. . .so I have NO idea why I keep asking!
There will be less parasitic loss of HP to the wheels, which in case, will show an increase in rwhp on an inertia dyno and not on a load (eddy current) dyno.
You will have an increase in the engines ability to accelerate, but there is a loss of kinetic energy with the decreased flywheel weight. This means the aluminum flywheel will cause your engine to rev faster from a low RPM launch compared to an iron flywheel, but if you were to dump the clutch from a high RPM on a launch, the iron flywheel will help keep the motor in the upper RPM range compared to the aluminum flywheel.
The heavier the flywheel the more potential energy it has, with a heavier flywheel the engine will hit the tires with more power/torque because it carries more potential energy...it's like swinging a pail of water with one gallon, and trying to stop it, versus 5 gal of water.... with all other variables being the same the 5 gal will be much harder to stop and carries much more momentum.
So what does all this mean? If you want to drag, go with the iron flywheel. AutoX, aluminum.
If none of this makes sense....tough...It's 3:30 in the morning!
You will have an increase in the engines ability to accelerate, but there is a loss of kinetic energy with the decreased flywheel weight. This means the aluminum flywheel will cause your engine to rev faster from a low RPM launch compared to an iron flywheel, but if you were to dump the clutch from a high RPM on a launch, the iron flywheel will help keep the motor in the upper RPM range compared to the aluminum flywheel.
The heavier the flywheel the more potential energy it has, with a heavier flywheel the engine will hit the tires with more power/torque because it carries more potential energy...it's like swinging a pail of water with one gallon, and trying to stop it, versus 5 gal of water.... with all other variables being the same the 5 gal will be much harder to stop and carries much more momentum.
So what does all this mean? If you want to drag, go with the iron flywheel. AutoX, aluminum.
If none of this makes sense....tough...It's 3:30 in the morning!
Um, this seems to have been passed up but I'm a little concerned. Why is your linkage popping out? Could this be an install problem?Equinox said:
slenser said:There will be less parasitic loss of HP to the wheels, which in case, will show an increase in rwhp on an inertia dyno and not on a load (eddy current) dyno.
You will have an increase in the engines ability to accelerate, but there is a loss of kinetic energy with the decreased flywheel weight. This means the aluminum flywheel will cause your engine to rev faster from a low RPM launch compared to an iron flywheel, but if you were to dump the clutch from a high RPM on a launch, the iron flywheel will help keep the motor in the upper RPM range compared to the aluminum flywheel.
The heavier the flywheel the more potential energy it has, with a heavier flywheel the engine will hit the tires with more power/torque because it carries more potential energy...it's like swinging a pail of water with one gallon, and trying to stop it, versus 5 gal of water.... with all other variables being the same the 5 gal will be much harder to stop and carries much more momentum.
So what does all this mean? If you want to drag, go with the iron flywheel. AutoX, aluminum.
If none of this makes sense....tough...It's 3:30 in the morning!
Do you mean the iron flywheel will keep you in the powerband longer between shifts? Sure a lighter flywheel will make your rpm's drop quicker, but then just learn to shift faster.
A lightweight flywheel will help you go faster..whether it be for drag or autox. It helps your engine rev faster, and the quicker your rpm's rise, the quicker your speed rises. The only downside of a lighter fw is decreased drivability, and 9lbs is still heavy enough to retain drivability.
Actually with the iron flywheel, you will have better 60' times and during your shifts, there will be less of a drop in RPMs (although it may be minute) when you engage the next gear. Meaning, the weight of the car itself will drag the RPMs down more.
herarety said:
the haevier flywheel will keep the engine momentum high. that means between shifts you have a greater chance of engaging again in the powerband but most importantly with additional momentum. have you tried to shift quicker in your protege with the stock tranny? many have and have found that the shift fork doesnt like that very much
the lightwieght flywheel will not make your car faster. it may make it quicker thru the gears but not faster. theres a big difference between the two.
and thirdly many can argue about the drivability of a lighter flywheel. some notice a change and some dont. IMO your car loses momentum in stop and go traffic situations
http://probetalk.com/forums/showthr...&highlight=lightweight+flywheel+rotating+mass
some more detailed info about lightweight flywheels. we can thank bigprobe (Darin here) for this insightful information.
some more detailed info about lightweight flywheels. we can thank bigprobe (Darin here) for this insightful information.
