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Old 04-15-2009, 10:30 PM   #321
GoingNuts
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Originally Posted by cngzsn View Post


This is exactly why you are not credible on this forum.
I am not here to be credible. I am here to prove light weight flywheel fails when used incorrectly. If I am not credible, no one will believe what I say. So why are you so concerned ?
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Old 04-15-2009, 10:37 PM   #322
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Old 04-15-2009, 11:56 PM   #323
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If heavier flywheels created more torque, why not just take to an extreme, let's have 500lb flywheels, surely a car with one of those would be way faster than anything on the street today

Seriously, how can anyone think that makes any sort of sense? A heavier flywheel will require more force to accelerate (in both positive and negative directions) than a lighter flywheel. That means it's more resistant to losing speed, which is probably why the factory fitted these cars with a heavier flywheel; they're meant for the average driver to cruise. Acceleration on the other hand will definitely suffer, as more force is required to spin up a heavier object.

Last edited by TerraPhantm; 04-16-2009 at 12:03 AM.
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Old 04-16-2009, 12:00 AM   #324
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Old 04-16-2009, 12:33 AM   #325
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Originally Posted by GoingNuts View Post
All the name calling and crying won't help. Nor any use punching walls.

Ok here's to use my formula to prove light weight UUC flywheel fails on a 2004 330Ci US spec:

------------------------------
Weight: 1490kg
Power: 225hp
Flywheel weight: 12.1kg

CoVU (330Ci) = 1490 x 225 / 12.1 = 27707

------------------------------
When the UUC 8.5lb (estimate) flywheel is used:

CoVU (UUC) = 1490 x 225 / 3.9 = 85961

------------------------------
Now compare that to the coefficient for a 2004 M3:

Weight: 1552.3kg
Power: 333hp
Flywheel weight: 11.8kg

CoVU (M3) = 1552.3 x 333 / 11.8 = 43806



The coefficient for the UUC flywheel is higher than that of the M3, ie, the 330Ci+UUC is more a racing car than an M3. This is fail. The flywheel is too light. The most extreme light weight flywheel for the 330 should be no less than 16.8lb. This will make the car as sporty as M3 in terms of drivability. Still that's optimistic to the extreme.
OR



honestly, cngzsn, does UUC's work look correct?
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Old 04-16-2009, 12:54 AM   #326
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Having plugged in various scenarios into my previously stated formula, I discovered it did not produce results I anticipated. So my first stab at the problem was fail. However the factors that I took into consideration remain valid. So rearrangement of the factors in the formula will produce a correct formula. Basically the flywheel acts as a force lever that moves the mass of the vehicle. The amount of available HP in relation to that lever is the primary concern. Varying the flywheel mass may affect the leverage in a detrimental way. This is what I believe a correct formula will prove.

Disregard last formula.

Last edited by GoingNuts; 04-16-2009 at 01:08 AM.
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Old 04-16-2009, 12:58 AM   #327
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Disregard last formula.
We already did.
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Old 04-16-2009, 01:01 AM   #328
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Originally Posted by TerraPhantm View Post
If heavier flywheels created more torque, why not just take to an extreme, let's have 500lb flywheels, surely a car with one of those would be way faster than anything on the street today

Seriously, how can anyone think that makes any sort of sense? A heavier flywheel will require more force to accelerate (in both positive and negative directions) than a lighter flywheel. That means it's more resistant to losing speed, which is probably why the factory fitted these cars with a heavier flywheel; they're meant for the average driver to cruise. Acceleration on the other hand will definitely suffer, as more force is required to spin up a heavier object.
In drag racing (for instance at the traffic lights), the launch rev'ing is done before the race begins. So the heavier flywheel carries greater stored energy at the moment of launch. This gives the car with a heavy flywheel an advantage. It is debatable if this advantage can be negated by the lighter flywheel car after the launch. If you can prove it, show it.

Last edited by GoingNuts; 04-16-2009 at 01:11 AM.
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Old 04-16-2009, 01:06 AM   #329
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Originally Posted by GoingNuts View Post
In drag racing (for instance at the traffic lights), the launch rev'ing is done before the race begins. So the heavier flywheel carries greater stored energy at the moment of launch. This gives the car with a heavy flywheel an advantages. It is debatable if this advantage can be negated by the lighter flywheel car after the launch. If you can prove it, show it.
what if it's a rolling start?

what if theres 50 laps to race around a track after the 1 lanuch?
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Old 04-16-2009, 01:42 AM   #330
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Don't bother arguing with Goingretarded. Same guy who is going for 30k mile oil change and who claims that he will swap out his transmission and the oil will outlast his transmission because it's got a stupid sticker saying it's lifetime oil.
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Old 04-16-2009, 01:42 AM   #331
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Quote:
Originally Posted by GoingNuts View Post
In drag racing (for instance at the traffic lights), the launch rev'ing is done before the race begins. So the heavier flywheel carries greater stored energy at the moment of launch. This gives the car with a heavy flywheel an advantage. It is debatable if this advantage can be negated by the lighter flywheel car after the launch. If you can prove it, show it.
Okay so a launch might be better. The car still has to accelerate past the launching RPM, and this will be slower because the engine now has to overcome the mass of the flywheel and the rest of the car. You're not going to get the energy to do that out of nowhere.
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Old 04-16-2009, 08:04 AM   #332
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Originally Posted by jeffro3000 View Post
what if it's a rolling start?
Then it would be called stock car racing.

It is an obvious point that a revving drag car with a heavy flywheel is actually able to build up stored energy in that flywheel that can be used to advantage when the Christmas tree lights up.

The variables that need to be addressed in the equation include:

1) How much potential energy can be stored in a heavy vs. light flywheel?

2) How much of that potetial energy can actually be applied to the rear wheels?

3) What is the positive impact on speed (since that is the goal) of the incremental applied energy?

4) What is the negative impact of speed of carrying the extra weight?

5) What are the other negative impacts of the alternative flywheel?


Quote:
Originally Posted by jeffro3000 View Post
honestly, cngzsn, does UUC's work look correct?
It is very important to choose the correct typing fonts when expressing your equations. As we can see, you can usually win over 90% of the minions by having a presentation that looks all official and everything.



.

Last edited by bmwbun; 04-16-2009 at 08:18 AM.
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