Lightening a 210mm flywheel+16v 2.0 pressure plate questions

[subsonic]

I have a 210mm flywheel.  I would like to have it lightened before I bring it in to be balanced.  My friend at the machine shop will do it on a lathe for me.  The problem is he has never lightened a vw flywheel before.  He said it would be very simple to remove the material off the heavy outer ring.  He asked me if I knew what dimensions I wanted it to be when it was done.  How deep do you want the cut, start and stop points, etc.  Never having owned a lightened flywheel before, I have no idea.  
Does anyone have anything detailed on this?
He said if I could come up with some good detailed photo's he could also make it work.
I am looking to bring it down to around 8-10 pounds.
Here are some photo's of the flywheel.  It is the one on the right.






Thanks, Jim

[zukgod1]

Ive not had it done Jim but comparing the 2 flywheels I would cut some of the thick ring off on by the ring gear.
If it were me I would just face that surface until it was where I wanted it.
I personally would leave about .250 of material there just for rigidity for the ring gear but I'm sure you could remove more if needed/wanted.

If that makes any sense at all.

[TedV]

cut off the thick outer lip from where the clutch plate bolts to the flywheel, leaving the ring gear.  for even less weight you can remove the surface that has all the VW, Germany and part numbers cast in, BUT you risk the flywheel cracking easier from less material thickness in the disk area.

[rabbid79]

I bought one that was lightened down to 6 or 7 pounds by Scooter Racing.  I can snap a few pictures of it if you'd like.

[subsonic]

Thanks, that would be cool.

[flapjack]

steel weighs .2836 lbs / cubic inch
measure the OD and ID of that ring and figure out how deep you want to go

[subsonic]

Talked to the guys in the shop.  They said no problem to take some off.  The concern they had was that if they get too close to the teeth, they will have nothing to clamp on when it comes time to resurface the flywheel down the road at the next clutch change.  Any of you run into this problem?

[flapjack]

I'm not a machinist
Wouldn't you flip the jaws and grip it from the inside?  



If you did grip it from the outside, how would the jaws of the chuck reach that ring?

[subsonic]

You would use the lathe to take off the ring.  When they resurface the flywheel, they use a grinding machine.  The flywheel lays flat inside the machine.  They clamp down on the outside ring, and lower the cutter / grinding stones/ head into the flywheel.  Kind of like a big ass CD cleaner.  I will try and snap a picture next time I am there.

[Gearhead]

I resurface flywheels on an automotive brake lathe all the time.  It can be done if you have the right machine.  That machine has to be a true positive rake machine with extremely rigid tooling, and a preloaded dovetail.  The brand I use is very similar in construction to a machinists lathe, not the common negative rake units that are common and cheap.  

When I do it, it's always clamped from the inside.  Many people think that grinding one on a flywheel grinder gets out the "hot" spots better, but a proper lathe will cut as deep as you like.  The flywheel grinder just masks the hot spots by putting a swirled surface.  I'm sure that if you have the flywheel lightened by a machinist, he would do a fine job of resurfacing it in the future.  His equipment and his knowledge is probably superior to a guy in a parts store with a flywheel grinder.  One thing to remember, if you remove alot of mass, the flywheel will more likely get "hot" spots and chatter earlier.  There isn't as much mass to dissipate the heat.

[hillfolk'r]

i took mine down to the ring gear,,well approx .100 before the ring gear
when i was done it weighed 7 pounds
BE AWARE THAT VW 210MM FLYWHEEL TDC MARKS DO NOT MATCH ON A DIESEL!!!
YOU MUST REMARK THE TDC MARK,or have fun next time you do a timing belt,cause you are screwed
use a piston stop to locate tdc on the flywheel

oh btw,i didnt bother to balance my fw,and it has over 100k on it

the weight is being removed pretty much evenly,and doesnt affect balance too much

[subsonic]

OK, so the flywheel will be getting lightened.  I'm going to leave about .250 in front of the ring gear.  Now I need to look at pressure plates.  I am going to need something fairly substantial.  From reading past posts it looks like something for a 16v 2.0. might be in the range of what I am looking for.  I won't be going all out with this engine all the time so I will probably be in the 170-180hp range.  The clutch will be researched soon, but I will need the pressure plate for balance purposes pretty soon.  I have seen some of the clutchnet stuff and it looks like it gets good reviews, but it's pricey.    Who has some good intel for me ?

[subsonic]

i took mine down to the ring gear,,well approx .100 before the ring gear
when i was done it weighed 7 pounds
BE AWARE THAT VW 210MM FLYWHEEL TDC MARKS DO NOT MATCH ON A DIESEL!!!
YOU MUST REMARK THE TDC MARK,or have fun next time you do a timing belt,cause you are screwed
use a piston stop to locate tdc on the flywheel

oh btw,i didnt bother to balance my fw,and it has over 100k on it

the weight is being removed pretty much evenly,and doesnt affect balance too much

How did you determine the correct location for the new timing mark?

[subsonic]

Now I need to look at pressure plates.  I am going to need something fairly substantial.  From reading past posts it looks like something for a 16v 2.0. might be in the range of what I am looking for.  I won't be going all out with this engine all the time so I will probably be in the 170-180hp range.  The clutch will be researched soon, but I will need the pressure plate for balance purposes pretty soon.  I have seen some of the clutchnet stuff and it looks like it gets good reviews, but it's pricey.    Who has some good intel for me ?

bump for holding power

[Turbinepowered]

How did you determine the correct location for the new timing mark?

Bump for needing this information too. About to swap a 210mm from the fox to the 1.5D.