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how to lighten Pinto flywheel?
DarrenW - 30/11/06 at 10:15 PM

Does anyone have any pics of a mildly lightened pinto flywheel so i can show a machine shop. Ive seen pics of radically lightened ones with grooves etc but i dont want to go that far.

I have it in my head that i dont need to touch the clutch face side at all. To the rear there seems to be a lot of material (guessing 10mm thick) that sticks out beyond the ring gear, i assume this is what can be removed flush to the side face of the ring gear.


flak monkey - 30/11/06 at 10:23 PM

I have some pics that might help

'Back' of flywheel:



Clutch side:



I have bigger, higher res ones if you need them.

Cheers,
David


DarrenW - 30/11/06 at 10:36 PM

Thanks David, they look perfect. I assume the first one is the back of the flywheel (opposite face to clutch side). It looks like most of the 10mm or so thick body i was talking about is removed.

2nd pic - clutch face side - has any been removed from this side?

Do you have any idea by how much lighter that one is? To be honest i dont know what they weigh as std and what a good target reduction is.


flak monkey - 1/12/06 at 07:56 AM

The first pic is of the side that faces the block.

It has had all of the rim removed, but i am not sure how much extra. The clutch faces looked like it had just had a light skim but nothing more.

I never weighed the flywheel, its still pretty heavy, at a guess I would say 5.5kg, perhaps compare that to your std one. I have a feeling they are over 6kg as std.

David


mcerd1 - 1/12/06 at 08:09 AM

There is a guide in the Des Hammil book on how much you can remove from a std pinto flywheel


flak monkey - 1/12/06 at 08:12 AM

Found the info: std flywheel is 6.4kg and it is possible to lighten the std one to around 4kg and it still be safe.

Mods to do that in the pic below (from the des hamil book).

Cheers,
David

Oops, sorry about the pic size

[Edited on 1/12/06 by flak monkey] Rescued attachment flywheel lightened.jpg
Rescued attachment flywheel lightened.jpg


DarrenW - 1/12/06 at 08:20 AM

Bloody hell!!!! I forgot about looking in the book!!! That is exactly what i was after, thanks.

(reminder to self - look at reference material before shouting for help)


Dusty - 1/12/06 at 11:24 AM

I personaly wouldn't want to put my feet beside a bellhousing containing a lightened cast flywheel.
If you must then don't take any off the center dished area. It has to weaken it and there is little point as the effect on momentum is minimal. Weight machined off the periphery is far more effective but I would limit it to removing the 10mm ring on the engine side like flak monkeys pic.


mcerd1 - 1/12/06 at 12:03 PM

quote:
Originally posted by Dusty
I personaly wouldn't want to put my feet beside a bellhousing containing a lightened cast flywheel.


My thoughts exactly - but steel ones arn't cheep (£160 for mine)


britishtrident - 1/12/06 at 04:01 PM

You should be able to start with a 1.6 flywheel and clutch big rotational inertia saving ---- you will get away with the smaller clutch in a Locost


Uphill Racer - 1/12/06 at 10:57 PM

Darren, this may be a stupid question, but, why do you want to lighten it?