Flywheel advice (come on old heads)
10-26-2010, 12:38 PM
#1
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Flywheel advice (come on old heads)
I need advice about running a lightweight flywheel in these cars. or should i get a stock replacement. i have an lsj if anyone is wondering.
10-26-2010, 12:40 PM
#2
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You can stick with a new stocker and they work great I have heard of some driveability issues with the light weights but its not stopping me from getting one.
10-26-2010, 01:00 PM
#4
as long as you know there are issues with aluminum flywheels;
I have heard repeatedly about the center hub shearing out...
on hte otherhand if you can get a lightened stock flywheel, that's probably hte best bet.
a lightened flywheel will not make a single extra HP, but it will allow you to rev faster (and in turn will make you loose RPM faster)...
I have one on my other GM-FWD car...
I have heard repeatedly about the center hub shearing out...
on hte otherhand if you can get a lightened stock flywheel, that's probably hte best bet.
a lightened flywheel will not make a single extra HP, but it will allow you to rev faster (and in turn will make you loose RPM faster)...
I have one on my other GM-FWD car...
10-26-2010, 01:53 PM
#5
Any rapid change in rotational velocity is sensed by the ECU as a misfire. Lightweight flywheels can cause this interpretation. My misfires have not increased noticabally in my logs since putting the LWFW on 15k miles ago. It does rev faster and is also easier to kill off of idle starting out. SPEC Stage2+ & SPEC LWFW here on an LNF.
10-26-2010, 03:22 PM
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Any rapid change in rotational velocity is sensed by the ECU as a misfire. Lightweight flywheels can cause this interpretation. My misfires have not increased noticabally in my logs since putting the LWFW on 15k miles ago. It does rev faster and is also easier to kill off of idle starting out. SPEC Stage2+ & SPEC LWFW here on an LNF.
10-26-2010, 03:23 PM
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as long as you know there are issues with aluminum flywheels;
I have heard repeatedly about the center hub shearing out...
on hte otherhand if you can get a lightened stock flywheel, that's probably hte best bet.
a lightened flywheel will not make a single extra HP, but it will allow you to rev faster (and in turn will make you loose RPM faster)...
I have one on my other GM-FWD car...
I have heard repeatedly about the center hub shearing out...
on hte otherhand if you can get a lightened stock flywheel, that's probably hte best bet.
a lightened flywheel will not make a single extra HP, but it will allow you to rev faster (and in turn will make you loose RPM faster)...
I have one on my other GM-FWD car...
10-26-2010, 05:27 PM
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Lightening the flywheel will increase wheel torque on a dyno measurement by reducing the moment of inertia of the drivetrain.
It is effectively chalked up as a drivetrain loss reduction, as opposed to a power gain.
It is effectively chalked up as a drivetrain loss reduction, as opposed to a power gain.
10-26-2010, 05:58 PM
#9
when you let off the gas pedal, that rotating weight will not abruptly reduce it's momentum unless another force is introduced;
with less reciprocating mass, your engines rotations are more susceptible to speed up quicker, and slow down quicker...
does that make sense?
EDIT:
here - this touches on it http://www.circletrack.com/enginetec...tia/index.html
better yet: http://stephenmason.com/cars/rotatio....html#flywheel
10-26-2010, 06:09 PM
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That being said there are some issues. Its up to you to decide if its worth it.
I knew a guy here in OK with an eclipse that had a LWFW and an aluminum drive shaft with 14lb wheels. He ended up putting back his old drive shaft on because his car would die constantly.
10-26-2010, 06:12 PM
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Its newtons 2nd law.
Force = mass * acceleration <-- this is the linear form of the equation
Torque = moment of inertia * angular acceleration <--this is the rotational form.
Torque is a fixed engine output, reducing the inertia yields increased angular acceleration (and deceleration consequently).
Then you look at the drivetrain system with the same equation
your angular acceleration is higher, the rest of your drivetrain inertia is fixed, therefore your wheel torque is higher.
Force = mass * acceleration <-- this is the linear form of the equation
Torque = moment of inertia * angular acceleration <--this is the rotational form.
Torque is a fixed engine output, reducing the inertia yields increased angular acceleration (and deceleration consequently).
Then you look at the drivetrain system with the same equation
your angular acceleration is higher, the rest of your drivetrain inertia is fixed, therefore your wheel torque is higher.
10-26-2010, 07:07 PM
#12
Where did you get your flywheel from? I get the random code in my car sometimes p300? is that the misfire your talking about? I was thinking about getting the fidanza LWFW from zzp with the gmpp clutch. I might be selling the exedy hyper single if you know anyone interested.
My SPEC stuff came from TurboTechRacing.
10-27-2010, 12:41 AM
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all theses decisions makes my head hurt. I have the exedy clutch right now and this has been my second transmission idk if this tranny was just beat a f and back before i bought it off here or what, but people keep telling me the clutch is to heavy for my setup. I never heard of anyone having a prob with it
10-27-2010, 07:21 PM
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all theses decisions makes my head hurt. I have the exedy clutch right now and this has been my second transmission idk if this tranny was just beat a f and back before i bought it off here or what, but people keep telling me the clutch is to heavy for my setup. I never heard of anyone having a prob with it
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