Why lighten the flywheel?
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    MIGWeb Moderator Paul's Avatar
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    Why lighten the flywheel?

    Any gen on the above ?
    Why do people have there's machined?
    Does it help the engine to rev better ?

    My engine is a 1.6 8v, any point in doing anything with the flywheel ?
    The engine is sitting in my shed floor at the moment, so its no extra trouble!

    Cheers,

    Paul

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    Engine revs up/down more quickly.
    Acceleration of car in 1st gear a few percent better, in 2nd a bit better, by 3rd gear no significant difference.
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    MIGWeb Moderator Paul's Avatar
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    Cheers Tom.
    You had yours done ?
    How much should I pay ?

    Hope your engine is coming on well, hope to see it at a MIG event this year.

    Paul

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    Re: Why lighten the flywheel?

    Originally posted by Paul Elwell
    Any gen on the above ?
    Why do people have there's machined?
    Does it help the engine to rev better ?

    My engine is a 1.6 8v, any point in doing anything with the flywheel ?
    The engine is sitting in my shed floor at the moment, so its no extra trouble!

    Cheers,

    Paul
    Makes fast gearchanges smoother, but makes sedate gearchanges lumpy, unless you balance the throttle.
    http://www.tssd.co.uk/index.htm How Tos . The two most life changing experiences you'll ever have. Finding Jesus, and having a baby.

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    Originally posted by Paul Elwell
    Cheers Tom.
    You had yours done ?
    How much should I pay ?

    Hope your engine is coming on well, hope to see it at a MIG event this year.

    Paul
    Had this done on my Cav GSI, made a HUGE difference to the way the car performed.
    It felt revvier and pulled alot easier because of it.

    65 exchange from our friends at SBD

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    if u get a lightened one fitted there is 1 bad point apart from the above is that the engine me idle rough due to the less momentum keeping the engine running


    am i right ne one???

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    Depends how much you lighten it. Mine idles fine.
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    RDS
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    Originally posted by nightrider
    if u get a lightened one fitted there is 1 bad point apart from the above is that the engine me idle rough due to the less momentum keeping the engine running


    am i right ne one???
    Nope cos mines got a 4kg one and it idles just fine
    Sir, please step away from the car

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    ive fitted a 2.0xe one to my c25xe .... not started it yet but hope it idles ok what u recon the benefits. disadvantages of it will be?
    Im a Daddy Wahoooo

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    Noz
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    There's huge benefits for the V6's, as their flywheels are absolutely monstrous. Because the markets Vauxhall sell in require some cars to tickover really really low, a big flywheel was put in as standard. Here in good old Blighty, the tickover doesn't have to as low, so the flywheel can be stripped to nearly nothing.

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    do u lose some top end by lightening the flywheel?
    roshan_j81@hotmail.com - Life moves pretty fast. If you don't stop and look around once in a while; you could miss it............

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    you don't gain or lose any power.
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    Right im off to try make an exhaust for the conversion gearbox fly and engine are in... let you know how i get on, if ne1's interested that is?
    Im a Daddy Wahoooo

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    one drawback of going really light is, the engine becomes very easy to stall.

    My belmont SXi used to conk out if you got to full lock!!

    Wife used to stall it a lot just reversing into the drive
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    > 65 exchange from our friends at SBD

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    too light a flywheel will cause rough idling.

    The reason is when a cylinder is on the firing stroke, a proportion the energy released from the combustion process is stored in the flywheel as rotational kinetic energy.(speed up)

    As a cylinder hits compression, energy is required to "do work" on the mixture in the cylinder, i.e. compress it. The stored energy is called on and hence the flywheel will lose rotational kinetic energy.(slow down)

    the energy transferred is called the "fluctuation of energy". If a flywheel becomes lighter, it stores less energy, so it's about finding the point where light becomes too light

    cheers

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    Modern engine management (Motronic onwards) have very good idle and anti stall programs. And a bigger engine will naturally have more inertia (bigger heavyer crank etc). Proberbly why RDS and others notice no difference in idling.

    On a cammed up smaller engine with carbs or something you would notice the difference proberbly. A rasie in idle speed will sort that though.

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    Don't pay 180 at SBD. Get your local engine rebuilders to do it for around 50.
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    MIGWeb Moderator Paul's Avatar
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    How much does a 1600 8v flywheel weigh ?
    Any ideas?
    How much shall I get it lightened by ?

    Cheers,

    Paul

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    why not get a f10 flywheel and clutch that would be lighter and still mate to a f13 or f10 box
    Stu.

    2 stroke tarmac terrorist

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    whats all this balancing the throttle malarky? what does it involve?

    oive just fitted an xe fly to my v6 cant wait to get it running
    Im a Daddy Wahoooo

  23. #22
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    Originally posted by garethbowers
    whats all this balancing the throttle malarky? what does it involve?

    oive just fitted an xe fly to my v6 cant wait to get it running

    You tap or hold the the throttle to get the engine and gearbox at the same speed, makes for very smooth gear changes.
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