Balancing a Lightened Flywheel

[chazrad 0]

Guys,

 

I've recently bought a lightened flywheel, which is in fact a VR6 standard flywheel machined down. It was done by a guy in South Wales who is known on a few forums for his gearbox rebuilds and other stuff (Club GTI especially). I've exchanged an email with him, and he can't be sure that he balanced it when he finished machining it down (he did the work back in Oct 07, and clearly does a few of these). It has also been said that I should get it balanced with my clutch to make sure there are going to be no untoward vibrations - all sensible stuff. Now, that all sounds like the car has got to be off the road for a while, whilst the present (standard and only 5000 mile old) clutch is stripped out of the car and sent away with the clutch to get balanced.

 

So the questions are:

1. How long will it take a workshop to strip the 'box out, remove the clutch, get the lightened flywheel and clutch balanced together, and refit it all?

 

2. Is it, in fact, worth me buying a new clutch and sending that off with the flywheel to get done together, then present the newly balanced bits to a mechanic to fit? I suspect I'll stick with the standard clutch as I've had no problems with the OE one on their atm, despite the stage 2 Vortech.

 

3. How much does balancing cost? Can't imagine its much. :D

 

Any help appreciated, fellas.

[Kevin Bacon 5]

Let me know if balancing the clutch and flywheel together makes a difference. I've got a slight vibration in my engine and I'm not sure if it's rotational or engine mount related.

 

Strictly speaking and being picky, you'd need a full balance, which involves balancing the Crank, crank pulley, flywheel and clutch as one big job lot. Awkward and expensive, but said to be the best possible balance.

 

And being pickier still, you should balance the gearbox to that lot aswell, LOL! :lol:

 

Seriously though, clutches are already balanced, well, the dealer supplied Luk is and the Helix Autosport is, so I'm not sure balancing it to the flywheel will do much??

But I am keen to see the results none the less.

 

Budget 4 hours to professionally remove the box, clutch and flywheel and refit it all.

 

Not sure how much balancing costs. I don't think it's that cheap!

[chazrad 0]

Kev, thanks for the advice.

 

I reckon I'll stick a new clutch on as much so I can get the flywheel and clutch off to a machine shop, sooner rather than later. Then I'll take it off to my specialist to get it all fitted. Got a different 'box to go on aswell! :D

[junkie 0]

When i had my 8v balanced it was all in the engine to the flywheel (inc) no clutch or gearbox lol balanced.

 

It may have its benefits to do the clutch as well but probably on track where you are in constant high RPM, so just do the flywheel as the matter of upmost importance.

[Yandards 0]

There are 2 types of balancing to consider and the one you need to use is dynamic balancing. The is where the component is rotated around its axis of rotation and balanced for even load throughout the rotation.

 

This does 2 very important things.

 

1. Reduces the vibration in the engine and allows higher engine speeds.

 

2. Gives more performance from an engine due to less energy being wasted to overcome the losses being generated by point 1.

 

Best bet is get the crank, pulleys, flywheel, clutch, clutch cover, conrods and pistons done as a job lot as well as getting the rods and pistons weight matched. I have a bill back in late 05 for £175 to do that and most of the cost was for lightening the flywheel.

 

http://www.vibrationfree.co.uk Steve Smith did the work, he is very good and based just a few miles away from Stealth. He does a lot of exotic engine blocks and has written some articles for Practical Performance Car on balancing.

 

And yes, manufacturers do balance items but as per usual it all comes to cost Vs effectiveness and the componenets are balanced in isolation(usually statically too), you will always get a better setup from having all the parts being dynamically balanced as an assembly.

[CTWG60 0]

http://www.vibrationfree.co.uk Steve Smith did the work, he is very good and based just a few miles away from Stealth. He does a lot of exotic engine blocks and has written some articles for Practical Performance Car on balancing.

 

And yes, manufacturers do balance items but as per usual it all comes to cost Vs effectiveness and the componenets are balanced in isolation(usually statically too), you will always get a better setup from having all the parts being dynamically balanced as an assembly.

 

Are you saying these guys can build a bottom end including, pistons and con rods attached to the crank and spin the lot and balance it? If they can surely this must be expensive?

[Yandards 0]

Yes he can, although he does most parts first in isolation then throws it all together ( you obviously need to supply the block too)

 

4 cylinder stuff is easy apparantly, its the big bore v8 etcs that cause headaches.

[CTWG60 0]

Yes he can, although he does most parts first in isolation then throws it all together ( you obviously need to supply the block too)

 

4 cylinder stuff is easy apparantly, its the big bore v8 etcs that cause headaches.

 

I don't know if you can answer this but what happens to the pistons running in the bores without oil and the shells. :scratch:

[Goldie 2]

A different gear box?? Details Charlie???

 

Sounds like this car is about to go from being really fast to stupidly fast...

[Yandards 0]

Yes he can, although he does most parts first in isolation then throws it all together ( you obviously need to supply the block too)

 

4 cylinder stuff is easy apparantly, its the big bore v8 etcs that cause headaches.

 

I don't know if you can answer this but what happens to the pistons running in the bores without oil and the shells. :scratch:

 

Shells go in but the oil is squirted into the bores for testing (no head obviously) - its only turned at a very low speed anyway - you dont need to rev it hard to enable balance, or lack of it, to be established.

[chazrad 0]

Yan, thanks for the advice. At the moment I have no plans to strip the engine down for balancing, although I can imagine the benefits. If I'd thought about it, I probably would have had that done at the time of my engine rebuild at Stealth 18 months ago.

So its just the clutch and flywheel that I have been lead to believe its worth balancing together. Frankly, its the flywheel that's of most importance because I don't know whether that has been balanced at all since being lightened. I'm in the process of finding a local machine shop that can sort me out.

[Yandards 0]

Yan, thanks for the advice. At the moment I have no plans to strip the engine down for balancing, although I can imagine the benefits. If I'd thought about it, I probably would have had that done at the time of my engine rebuild at Stealth 18 months ago.

So its just the clutch and flywheel that I have been lead to believe its worth balancing together. Frankly, its the flywheel that's of most importance because I don't know whether that has been balanced at all since being lightened. I'm in the process of finding a local machine shop that can sort me out.

 

The addition of the crank to that does make a difference but in theory all the individual bits should been individually statically balanced by VW to within their tolerances. Still worth doing the flywheel, clutch and clutch cover plate though.