View Full Version : d.i.y lightened flywheel
jimbob-mcgrew
20-07-08, 12:36 AM
is it possible to do this yourself by finely marking out and drilling a bunch of holes in it, without upsetting the balance of it too much, im curious, proper ones are expensive
i wouldnt bother, people in the past that have lightened a flywheel by drilling or skimming and have had there ones shatter and even come through the front of the car
tom reid
20-07-08, 12:40 AM
Dont do it, lol, you'll just end up ruining a perfectly good flywheel.
How expensive is too expensive?, a properly modified std item isn't that expensive, imo.
Seriously dont attempt it.
You could put hairline fractures in it which then may lead to it shattering at 6000rpm and heading into the car/its passengers.....
jimbob-mcgrew
20-07-08, 12:43 AM
hah - 3 replys within less than 5 minutes saying dont do it
~~joycey~~
20-07-08, 12:46 AM
Yeah i heard from a mate about some one's flywheel shattering and it cutting through bonnet/gearbox ect!?
tom reid
20-07-08, 12:51 AM
hah - 3 replys within less than 5 minutes saying dont do it
Good advice though
LOL yep, it will have no problems munching the ali of the gearbox and the bulkhead/front end when it decides to leave at a few thousand RPM.
Suicidal pikey mod IMO. Cut springs, it's safer.
dumpycorsa
20-07-08, 04:38 AM
I bought one a while back from a shop on ebay. Flat type xe fly wheel.Just needed to add the starter gear ring from the old fly wheel. Took it into work and crack tested it, de-magnitised it, checked the balance, clocked the starter gear ring in on a marking out table then weighed it. It now weighs 3.6kg. Paid £125 for it. Wouldn't risk lightening it myself as it could cause dangerous imperfections. This one was done on a cnc mill ensuring all the holes were evenly spaced. Even so I still had ot checked for cracks and checked it was balanced before I fitted it to the engine.-
Removing the gear ring using a Oxyacetylene torch
http://i41.photobucket.com/albums/e251/trish26gordon/DSCN3683.jpg
Then heated up again and fitted on to the new fly wheel. Ideal
http://i41.photobucket.com/albums/e251/trish26gordon/DSCN3685.jpg
now this i would not want to happen to my car!!! also what is worrying is what it could do if some parts got into the passenger compartment when the seat is occupied... :eek:
http://i70.photobucket.com/albums/i95/ckallis500/flywheelbang.jpg
http://i70.photobucket.com/albums/i95/ckallis500/img00010ft4.jpg
http://i70.photobucket.com/albums/i95/ckallis500/img00007ic7.jpg
http://i70.photobucket.com/albums/i95/ckallis500/img00001tt0.jpg
http://i70.photobucket.com/albums/i95/ckallis500/img00003te3.jpg
http://i70.photobucket.com/albums/i95/ckallis500/img00004yt5.jpg
http://i70.photobucket.com/albums/i95/ckallis500/img00005zo7.jpg
http://i70.photobucket.com/albums/i95/ckallis500/img00006ao7.jpg
http://i70.photobucket.com/albums/i95/ckallis500/img00008dk3.jpg
http://i70.photobucket.com/albums/i95/ckallis500/img00009lm5.jpg
tbh it is dam right dangerous when done and why people want to do it anyway i havent got a clue. even if they did lighten the original one it still would never be as light as a proper one, and is it really that much more money.
Philsutton
20-07-08, 12:59 PM
as said dont do it, a flywheel at 7k will have a serious amount of energy and not alot is going to stop it if it comes off (which is what it will do if its not 100% balanced right).
i had mine done by a big rally/race shop. cost me 90 euro, and it weights a good 5kg.
i had mine done by a big rally/race shop. cost me 90 euro, and it weights a good 5kg.
you havent got that in your car have you? if you have i would do any high revs!
you havent got that in your car have you? if you have i would do any high revs!what makes you say that
have you seen the pics that ck posted. i would just never trust a lightend flywheel done buy a shop yourself ect. ive seen what can happen and how weak then can get
well if you dont want a lightened flywheel done by a shop how do you plan on having one
buy a shop i mean as in use the original one and go to a work shop and get them to put it on a lave and shave it down. i would buy one from courtenay sport ect
Philsutton
20-07-08, 01:31 PM
^^ courtney sport just shave down theirs???
bigs i think your being silly lol
^^ courtney sport just shave down theirs???
:confused: am i getting this very wrong then. who is it that uses a lighter material instead of just shaving them down
errr very few people as that costs lots of pennies
bigs i think your being silly lol
you got me thinking i am aswell now lol
im sure someone told me a place that uses a lighter metal thats how they get a light flywheel :confused: hmm now you got me thinking if i just dreamed that :roll:
Welsh Dan
20-07-08, 01:36 PM
I can make you a fibreglass one if you like. ;)
I can make you a fibreglass one if you like. ;)
prefer if it was carbon :D
Philsutton
20-07-08, 01:37 PM
Hardly anyone uses different material as thats cost loads. Its is the best way to do it though.
Yea ones ive seen are around £250 - £300 so im not dreaming then.
Austin_Nova16
20-07-08, 01:43 PM
You talking about the fidenza (sp?) flywheels? Alloy with a bolt on friction part......
yea thats the one, very well made
Philsutton
20-07-08, 01:49 PM
TBH I cant say much really as Ive gypo worse things on the corsa light shaving down my pistons lol
jimbob-mcgrew
20-07-08, 02:17 PM
fkinell u see those pics, chomped thru the rad and bumper on that nova with ease by the looks of it. and the calibra - took the dizzy off clean and punched a hole thru the bonnet, hopefully some poor fcuker in the next town didnt have that lump of disc come down on them like a meteorite.
after seeing those pics and hearing what everyone has to say about the matter, not even sure if i wanna risk messing with a professionally done one now
white2lSR
20-07-08, 04:23 PM
im liking the pics of the flywheels making sharp exits lol
Yeah they can be dangerous,imagine a Stihl saw with a blade as thick as your flywheel plus a clutch bolted to it exploding.........carnage lol
dhdev (Oli)
20-07-08, 04:42 PM
Get it done properly http://www.autosprint.co.uk/?p=p_43
i would no way trust a lightened standard flywheel, once machined it cant be heat treated properly again to get its strength back. most ppl that lighten them can only take them down a very small amount and generaly only take material from the rear surface.
courtenay flywheels are steel billet, my friend has one on his LET. i used to run a fidanza alloy flywheel on my LET the std flywheel was around 9.5kg's (pot type) and my fidanza was only 3.5kg's. the steel ones arent as light.
dumpycorsa
20-07-08, 06:09 PM
the steel ones arent as light.
Mine only weighs 3.6 kgs with out a starter gear ring
yeah, my pot type fidanza was 3.5kg's with starter gear. the flat type i think was 3.2kg's with the starter gear.
you havent got that in your car have you? if you have i would do any high revs!
its in my c20xe nova..
Hey? I had mine lightened and balanced at a machine shop, cost about £30. I didn't want to take too much off mind.
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