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Hi,

Was wondering if anyone had any experience of a lightened flywheel on the M52 or M54 engines?

After good manufacturers, any negative aspects noticed (like vibration etc)

Thanks in advance :)
 

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a lightened flywheel wont idle as steadily as a stock item, and it wont absorb any vibrations from the engine as well as stock
it'll allow faster acceleration of the car and the revs will rise and fall much quicker
 

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how will it make the car drive ? would it become a pain ? intrested to here from some one who has done this mod ? or still has it.
 

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Lightened flywheels can put more strain on the gearbox/drive train, also the engine can stall easier when pulling away so more revs are required. :thumbsup

Especially light flywheels can give a lumpy tick over.
 

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would a lighter fly cause more probs on a smaller or bigger engine ?
More problematic on a smaller engine, less cylinders equals rougher tickover, and due to the idle being "preset" it's not a simple task of winding the idle up, it needs to be done by reprogramming.(that's if the idle was really poor/using a very light flywheel, Seen it done on a E39 M5 years ago. JB racing flywheel)
 

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i see / i find little engines are very revy so that makes sence / i was asking cus i find big engines take a while to get going so was thinking along the path of making the 2.8 engine a bit more free reving but dont want idle probs am going to try the under drive pulleys first . do you remember what the m5 was like with the lighter fly
 

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i see / i find little engines are very revy so that makes sence / i was asking cus i find big engines take a while to get going so was thinking along the path of making the 2.8 engine a bit more free reving but dont want idle probs am going to try the under drive pulleys first . do you remember what the m5 was like with the lighter fly
No, was ages ago, I remember we had to up the idle as it was too low/really lumpy.
 

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I was running a chromoly steel lightened flywheel last year.


Saved 7kgs over the standard dual mass, quite a big saving. Easy swap, just need to removed the gearbox which is the tricky bit.



i used an m3 clutch and clutch cover, and also changed the clutch slave to an m3 one as well as the original gave up the ghost almost instantly.

This coupled with the viscous fan delete make the engine rev and pick up significantly quicker in all gears, most noticeable in first and second where it revved out very quickly.

Idle was not an issue, the ICV stablizes it quite quickly.

A good mod if you looking for a bit extra, all the little bits do add up if you do them
 

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cool sounds good were did you get your fly from what car did you have it on ? the fan delete do you just take of the viscous fan then .what do you need to do after that
 

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yes it will cost a good few£££. I haven't heard anyone mention the gearbox chatter thatyou get from a lightened flywheel. When not in gear it sound like a bg of spanners in your gearbox. Saying that it will depend on how light you go, the lighter it is the more noise. The guys with E36 M3's compensate for the noise a bit by going for the E34 M5 clutch and pressure plate as it is sprung so helps dampen noise a bit, doesn't eliminate it totally. Worth bearing in mind as a few people have changed back due to the noise being too much for them!
 

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that is good info. no one has yet said there will be a noise prob ! is that a deffo or just could be bad?
Yeah, due to the slightly more erratic tickover you get more vibrations, which can indeed transmit through to the gearbox , :frown
 

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I've got a UUC stage 2 fly and clutch setup in my 328 e36. The rattle is quite noticeable at idle. I've had it described to me as a small tractor in my gearbox. The kit i have on my car has made driving in traffic a bit of a pain. There is no noticeable power increase neither does it noticeably rev up faster.No one has mentioned the risk of a light weight flywheel. Light flywheels have been known to snap and fly through cars or warp. All in all I am still happy with the product. The slip isn't ideal as said before but it is bearable.
Underdrive pulleys will not gain you more power. They are a lot of money just to make your car less reliable.
 
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