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Standard flywheels shouldnt be machined i thought?

...tell me when to start laughing...

But seriously, why did you think that? If you think about it for a minute (and no i'm not a mechanic) if your flywheel face that the clutch face will be coming into contact with, is not PERFECTLY flat on installation of a new clutch, how is that new clutch suppose to operate at its peak performance? i mean u have a flat surface (clutch face) trying to mate to a non flat surface (flywheel face), there will be less load dispersing and may in the end cause major slippage, especially in the case of a button clutch (i know from experiance)

this is why the flywheel needs maching

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...tell me when to start laughing...

But seriously, why did you think that? If you think about it for a minute (and no i'm not a mechanic) if your flywheel face that the clutch face will be coming into contact with, is not PERFECTLY flat on installation of a new clutch, how is that new clutch suppose to operate at its peak performance? i mean u have a flat surface (clutch face) trying to mate to a non flat surface (flywheel face), there will be less load dispersing and may in the end cause major slippage, especially in the case of a button clutch (i know from experiance)

this is why the flywheel needs maching

Thatsdead right. Flywheel just like your brake discs, they are made to be machined within certain specifications, once the flywheel has become undersize then it can not be machined(or rather should not be).

11 hours labour is complete crap anyhow!!!!!!!!!

true, but you must be going through some clutches to have machined the flywheel that much :D

first time i did my box in the gtr it only took me 5hrs that was up the back in the carport with the car on axle stands, that's including mis-aligning the box 4 times too :laugh:

true, but you must be going through some clutches to have machined the flywheel that much :D

first time i did my box in the gtr it only took me 5hrs that was up the back in the carport with the car on axle stands, that's including mis-aligning the box 4 times too :D

Not necessarily machined that often to have them undersize, Clutch faces some harsh punishment in many cases and develop hard spots on the surface which can be difficult to machine and require a larger cut to be taken. Obviously this is normal, but in some instances those hard spots change the metal properties and can lead to some surface cracking on the flywheel, this needs large cuts to get them out and like anything, before you know it "UNDERSIZE."

Dont it shit ya when you mis-align the clutch spline. We have all been there before. As you stated 5 hours on axle stands, what the hell can you do to waste 11hrs, better check the clutch it may have been polished or something

...tell me when to start laughing...

But seriously, why did you think that? If you think about it for a minute (and no i'm not a mechanic) if your flywheel face that the clutch face will be coming into contact with, is not PERFECTLY flat on installation of a new clutch, how is that new clutch suppose to operate at its peak performance? i mean u have a flat surface (clutch face) trying to mate to a non flat surface (flywheel face), there will be less load dispersing and may in the end cause major slippage, especially in the case of a button clutch (i know from experiance)

this is why the flywheel needs maching

Im pretty sure they are hardened on the outside and as such should not be machined.

Your obviously a budget racer so dont worry about buying a new lightweight one :D

Im pretty sure they are hardened on the outside and as such should not be machined.

I've heard this before so many times it isn't funny. While what you say may be true it has absolutely no long or short term negative efects whatsoever.

Someone PROVE me wrong?!?!?! In practice, not theory please.

Adrian

Im pretty sure they are hardened on the outside and as such should not be machined.

Your obviously a budget racer so dont worry about buying a new lightweight one :rofl:

lol...someone else please explain to this man what i tried to explain to him :D

thought so...jim berry has explained to me the advantages of running a stock flywheel in a drag situation against a lightened one

but if it was a track dedicated car and every 10th was imperative to win, then a lightened flywheel would be 'necessary'

thought so...jim berry has explained to me the advantages of running a stock flywheel in a drag situation against a lightened one

but if it was a track dedicated car and every 10th was imperative to win, then a lightened flywheel would be 'necessary'

blah blah budget racers rekon everything is sweet

someone saw you coming...

wasn't Mercury Motorsport was it? Wouldn't surprise me if it was

LoL..

A mate of mine had bad experience with them.

He took his evo to merc to get a HKS suction kit fitted. They fitted the kit wrong and when my mate picked up the car he noticed that the car was cutting out when idle. Their reasoning was that putting a new suction kit can throw the AFM out of wack.

He took the car home and looked at the picture of the setup in the manual. Even though the manual was written in japanese he could workout that the pipe was fitted the wrong way, hence the AFM was in the wrong position. Once he rectified the prob made by Merc Motorsport, the car was perfect.

That wasnt the end of it. There was also a bracket for the kit that Merc said they "miss placed". It turned out that they left it inside the engine bay and forgot to take it out. It wasnt until the car was taken to stafford tune for a MOTEC install an tune that the tuner heard a weird sound comming from the engine and found that the bracked was lodged in one of the gaps in the engine....

He rang them back and told them about the dodgy job they did. They actually admitted to screwing up the fitting. Meaning they admitted that they are deadshit :D Great work Merc Motorsport! Ill make sure that ppl i know will never take their cars to Mercs workshop :P

Edited by Blitz_R33
lol alrite then, dont go having a cry when ur ultra light flywheel decides to bend/warp and u need to buy another ~$500 one :D

Had my ORC one for 2 years now, no problems at all. Will be sure to post up if it has any problems but since top secret use them on their cars i doubt it!

rofl

Had my ORC one for 2 years now, no problems at all. Will be sure to post up if it has any problems but since top secret use them on their cars i doubt it!

rofl

If you ever have a free 30mins to ponder stuff, ring up Jim Berry about that. Should be fun.

If you ever have a free 30mins to ponder stuff, ring up Jim Berry about that. Should be fun.

Id rather call "time man" i have about as much need for him as jim berry.

If you want to cut corners thats fine with me, however thats not always good enough for everyone.

Perhaps you should ask sydneykid about his thoughts on lightweight flywheels, then get back to this thread.

EDITED by Col

Flywheels are designed to be machined. I have machined mine 4 times now and it has been lightened as well. They have plenty of meat on them to do so. The factory flywheels are fairly strong so many people like to retain them instead of a lightened one as the lighter or thinner the flywheel, the more prone it will be to warpage.

Factory flywheels are not case hardened, they are cast iron. The flywheels that are difficult to machine are the rotary ones which are made of steel. They must be done on a lathe or special grinder.

Cracks in the face mean shit. You can machine the flywheel flat, still see cracks in the surface and it will never cause you any problems in a million years.

I am not sure if all of the above applies to every car on the market but for skylines at least, it does. I have machined a few hundred flywheels this year and about 30 of them were skyline. Of them, none of the factory flywheels were a throwaway. I have been sent 2 lightened ones and 1 of them was a throwaway due to excessive warpage.

Lightened Flywheel for the turbo car....best upgrade I've ever made. (NA different story)

The Engine is more throttle responsive.

Gets to revs quick...gets to power band sooner (Turbo spools up quicker)

Loss of Torque???...Didn't notice it at all.

RIDE the Clutch off the start (progressively loading the Engine)

Dropping it....keeping your fingers crossed...only for the useless dumbie.

Bad Workshops and individuals everywhere. Everyone has been ripped off at one time or another.

Honesty....A dying Art.

Also...nothing wrong or cheap about machining a STD flywheel, but be aware that most are only cast and were designed to handle a particular loading...normally stated at plus 30%.

Lighten flywheel....Billetted steel.

Other than minimal face machining...never lighten a CAST flywheel (your reducing the design capacity)

regards Phillip

I did actually find my car was easier to drive, had less right off the line ie up to 2000rpm, but after that it was better boost came on quicker etc. That said I didnt have a billet steel light weight flywheel before hand. I had some super dooper crazy jun lightweight thing made out of some exotic metals from jupiter which was extreamly light, so maybe that was the difference. Either way a few of my mates went to heavier than standard, or back to standard to gain speed and reduce lag, it worked. Its that simple.

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