ned
|
| posted on 10/2/05 at 02:41 PM |
|
|
Small flywheel ring gear
As my engine keeps growing in power I'm having to rethink the clutch arrangments and at the same time it makes sense to get a nice small
flywheel made up to suit.
I'm thinking of using a 7 1/4" clutch so am after a suitable ring gear that is slightly larger than this so I can get the flywheel as
small as possible to get the weight and centripital forces down so the engine will spin up a bit quicker.
So does anyone have any tips on cars with small flywheels that I could use the ring gear from?
I know the likes of sbd sell small flywheels but this defeats the point as they cost a lot more than the local engineering firm could turn me one up
for.
Infact there is a full size steel flywheel I might be able to turn down on my friends lathe, so it could be virtually free to do...
Cheers,
Ned.
ps for any clever clogs yes I know I'll need to change the starter motor so it'll engage a smaller flywheel.
[Edited on 10/2/05 by ned]
beware, I've got yellow skin
|
|
|
|
|
James
|
| posted on 10/2/05 at 03:07 PM |
|
|
Are ring gear teeth the same profile universally?
Only asking as I wonder if your starter motor will need the gear changed to match the ring gear tooth profile?
Cheers,
James
|
|
|
timf
|
| posted on 10/2/05 at 03:10 PM |
|
|
quote:
Originally posted by ned
Infact there is a full size steel flywheel I might be able to turn down on my friends lathe, so it could be virtually free to do...
[Edited on 10/2/05 by ned]
ned ever seen a flywheel expode due to being lightened to much.
they tend to go through bellhousings etc.
In this case buy a professionally made item, its your life your toying with
|
|
|
ned
|
| posted on 10/2/05 at 03:19 PM |
|
|
Tim,
I'm not going to turn down a standard cast flywheel, but a billet steel race flywheel. I'm not that stupid!
I have a friend who's flywheel on his racecar is only marginally bigger than the 5.5" quartermaster sintered clutch he runs, now that is
small!
Ned.
ps james if I'm gonna change to a smalelr starter motor I can change the cog on it if it is a different profile, so again not an issue...
[Edited on 10/2/05 by ned]
beware, I've got yellow skin
|
|
|
Alan_Thomas
|
| posted on 10/2/05 at 05:26 PM |
|
|
Ned, If you go for a smaller flywheel it will be more than changing the profile of the starter sprocket. Any significant reduction in diameter will
require the starter to be moved a lot nearer the crank and that will require a new rear engine plate.
Most folks lighten flywheels by reducing the thickness thus reducing the moment of inertia. This allows std ring rear and starter to be used.
If you lighen the flywheel too much you end up with powerful engine but undrivable car. I skimmed the flywheels of a motorbike once took off to much
and whilst it 'picked up' very quickly it also stalled at the slightest whim.
On my own crossflow setup I have fitted an 1100cc flywheel, lighter but no changes required
- Alan
|
|
|
NS Dev
|
| posted on 10/2/05 at 05:42 PM |
|
|
I think you would be better to make a "skeleton" flywheel Ned, you will struggle for space on the XE to get the starter near enough to the
ring gear otherwise. A really thin skeleton one would be almost as light as a small diameter one anyway in real terms, and a lot easier to do.
If you are starting from a steel flywheel from unknown source then be careful, if it's very thin and minimal it will need to be made from
something such as EN24T plate to be strong enough. You could verify the steel used on the one you have. (you could get it spec tested with a spectro
test machine, we have such things and they are great, your local large scrap metals merchant will probably have one and let you do a test with it.
|
|
|
britishtrident
|
| posted on 10/2/05 at 05:58 PM |
|
|
Its a can of worms apart from the considerable technical hurdles making the flywheel too light on a road car will makes it very unpleasant to drive, I
don't enough about the family of engines your engine comes from but you may find a lighter flywheel from a smaller capacity version is a good
starting point.
|
|
|
