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why are lightweight flywheels bad for turbo

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Old 05-18-2002, 05:57 PM
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Default why are lightweight flywheels bad for turbo

just wondering
Old 05-18-2002, 06:15 PM
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Default Re: why are lightweight flywheels bad for turbo (94goldjungsr)

who said they were? I have a Clutch Masters flywheel with an Underdrive Pulley for nearly 2 years now and I love it. Haven't had any problems.
Old 05-18-2002, 06:50 PM
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Default Re: why are lightweight flywheels bad for turbo (PressurizedB18C5)

thats what i was gonna ask... who said they were bad?
Old 05-18-2002, 06:57 PM
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Default Re: why are lightweight flywheels bad for turbo (ek9t)

I remmber way back when reading threads about how having a lightweight flywheel with a turbocharged car was not advised... can't remember the argument though.
Old 05-18-2002, 07:34 PM
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Default Re: why are lightweight flywheels bad for turbo (94goldjungsr)

gaining quicker rpms = faster turbo spool
Old 05-18-2002, 08:28 PM
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Default Re: why are lightweight flywheels bad for turbo (sushibug)

I have a 7.5 LB Clutchmasters flyhweel mated to a Clutchmasters Stage 4 clutch and have NO PROBLEMS with the combo. I love the combo on my car. engagement is pretty smooth and turbo spools up slightly quicker.
Old 05-18-2002, 08:45 PM
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Default Re: why are lightweight flywheels bad for turbo (BG Boost)

8 lbs flywheel with a turbo B18c1= awesome spool.

The only downside of a lightened flywheel with a turbo is that is harder to launch smoothly on the quarter mile . But you get used to it with some practice!


[Modified by meanteg, 5:52 AM 5/19/2002]
Old 05-18-2002, 09:08 PM
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Default Re: why are lightweight flywheels bad for turbo (94goldjungsr)

harder to keep consistent launches, hurts fuel economy slightly, makes daily commute a little more of a bitch or a little more fun depending how your drive
Old 05-18-2002, 09:32 PM
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Default Re: why are lightweight flywheels bad for turbo (94goldjungsr)

I remmber way back when reading threads about how having a lightweight flywheel with a turbocharged car was not advised... can't remember the argument though.
there are reasons why gettin a flywheel isnt good... but then again, there are also advantages. do a search.. there are a couple of threads on this subject. i saw one recently on what type to use.
Old 05-19-2002, 10:00 AM
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Default Re: why are lightweight flywheels bad for turbo (94goldjungsr)

Lightweight flywheels are not bad necessarily. i shaved 5lbs off my stock one for my turbo application and i can tell a difference when i lauch, the rpm's go up a lot faster. The bad thing about it is for top end. The only really way i can explain it is by describing a mountain bike gearing. Say you have a 10 speed, if you start out in 10th gear (highest gear) it requires so much work to start peddling from a stand still, however; if you are in 1st gear you can take right off. Now.... say you have your momentum up and are going lets say 25mph on a bike. Try to peddle in 1st gear, it is impossible bc it is such a low gear, you need a higher gear say 7-10 and then you barely have to peddle to produce a greater amount of speed. You can apply this theory to your lightened flywheel, its not exactly the same.... but i think you guys can get the idea.
Old 05-19-2002, 10:03 AM
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Default Re: why are lightweight flywheels bad for turbo (GudeH23a)

I beleive a stock one weights 19lbs.
Old 05-19-2002, 11:14 AM
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Default Re: why are lightweight flywheels bad for turbo (CashedEG)

I beleive a stock one weights 19lbs.
you talking ls,gsr or r?
Old 05-19-2002, 06:20 PM
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Default Re: why are lightweight flywheels bad for turbo (tonydatyga)

They are all the same...
Old 05-19-2002, 06:32 PM
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Default Re: why are lightweight flywheels bad for turbo (Bnjmn)

actually type r's use lightened flywheels, 15lbs I believe they are
Old 05-19-2002, 07:22 PM
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Default Re: why are lightweight flywheels bad for turbo (Bnjmn)

They are all the same...
actually, no, they aren't.

from memory when I weighed a bunch I had laying around

LS - 19lbs
B16a - 17lbs
B18c - 17lbs
B18c5 - 15lbs

Personally, I like about a 12lb flywheel. Lighter than stock, yet not so light that all you do is spin. Easy on the daily driver too



[Modified by VaporTrail, 11:22 PM 5/19/2002]
Old 05-19-2002, 10:16 PM
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Default Re: why are lightweight flywheels bad for turbo (VaporTrail)

The main reason i've heard is that you need the mass on teh flywheel for launches.
Old 05-19-2002, 10:20 PM
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Default Re: why are lightweight flywheels bad for turbo (94goldjungsr)

I wouldnt say they are bad for turbo, I would just say they arent really nesseccary. U can go fast on a stock flywheel.
Old 05-20-2002, 07:03 AM
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Default Re: why are lightweight flywheels bad for turbo (94goldjungsr)

Anyone turboed tried the Exedy chromoly flywheel? i plan on going with that one in the near future...9lbs. i believe...


Old 05-20-2002, 08:05 AM
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Default Re: why are lightweight flywheels bad for turbo (TheSwift1)

I think th exedy flywheel is 9.1lbs.
Old 05-20-2002, 10:20 AM
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Default Re: why are lightweight flywheels bad for turbo (smeister)

Where are the best places to get one for a D16y8? I've searched on the Internet and only find them for the DOHC motors.
Old 05-20-2002, 12:19 PM
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Default Re: why are lightweight flywheels bad for turbo (94goldjungsr)

I posted that once years ago, for guys running T25 and t3/t4 57 trim ... on a FWD car, there is almost no traction with a lighter flywhell becuase everything spins so fast, but on a big turbo, it spools much quicker .... so you can't generalize the statement, you have to determine combination.

Greg
Old 05-20-2002, 08:33 PM
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Default Re: why are lightweight flywheels bad for turbo

If you usually road race, race from a roll, or autocross, the lightened flywheel will help you accelerate faster, and generally be a good choice.
If you are into drag racing and want to improve your times, a lightened flywheel will likely hurt your times rather than improve them. Someone explained to me once that the flywheel stores a certain amount of energy, so when the clutch engages with it from a stop, you can get moving faster. If there isn't enough energy stored at the flywheel for your launch, you are going to lose crucial milliseconds that would better your final ET.
Old 05-21-2002, 09:20 AM
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Default Re: why are lightweight flywheels bad for turbo (degradated)

...inertia...
Old 05-21-2002, 09:51 AM
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Default Re: why are lightweight flywheels bad for turbo (degradated)


<U></U> If you usually road race, race from a roll, or autocross, the lightened flywheel will help you accelerate faster, and generally be a good choice.
If you are into drag racing and want to improve your times, a lightened flywheel will likely hurt your times rather than improve them. Someone explained to me once that the flywheel stores a certain amount of energy, so when the clutch engages with it from a stop, you can get moving faster. If there isn't enough energy stored at the flywheel for your launch, you are going to lose crucial milliseconds that would better your final ET. <U></U>
excellent explanation
Old 05-21-2002, 10:56 AM
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Default Re: why are lightweight flywheels bad for turbo (cjblmr)

Easy to understand, but slightly incorrect (degredated)...

Inertia = the resistance an object has to a change in its state of motion.

Inertia is solely dependent on mass. More mass = greater amount of inertia

Therefore: lighter flywheel resists changes in state less (accelerating, spin faster), but when no more force is being applied from acceleration it is more likely to succumb to the reactionary forces of friction in the engine (lose revs quicker).

I don't drag race, but in autocrossing you need to maintain speed through the corners, not rely on acceleration. A lighter flywheel can make this more difficult since your revs drop quicker. This is why my civic si can turn faster times than a
&gt;400 hp supra (nice guy driving it though). That car obviously accelerates faster than I do.

Guess this does not answer the question posted, but maybe it sheds insight to the mystery of light fly wheel acceleration gains (bearing you have traction).

Oh, and I am not a physics professor so if I am wrong don't hesitate to correct me.


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