Omega Owners Forum

Chat Area => General Car Chat => Topic started by: azza_126 on 20 October 2011, 21:02:03

Title: solid flywheel
Post by: azza_126 on 20 October 2011, 21:02:03
can you get a solidflywheel to replace the duelmass one on the 3l v6?
Title: Re: solid flywheel
Post by: TheBoy on 20 October 2011, 21:32:11
I'm sure the pillocks such as the likes of Courtney 'Sport' (in the loosest sense) will do a lightened flywheel, which probably isn't dual mass.

What are you hoping to achieve (sorry if I've missed a thread)
Title: Re: solid flywheel
Post by: serek on 20 October 2011, 21:41:00
can you get a solidflywheel to replace the duelmass one on the 3l v6?
you can use fly wheel of vectra B V6 its direct swap but you need clutch from vectra too,
Title: Re: solid flywheel
Post by: cem_devecioglu on 20 October 2011, 22:02:16
can you get a solidflywheel to replace the duelmass one on the 3l v6?
you can use fly wheel of vectra B V6 its direct swap but you need clutch from vectra too,

yep, I preferred that route and no probs.. and even the clutch kit is 1/3 price of the other here..
Title: Re: solid flywheel
Post by: serek on 20 October 2011, 22:11:48
can you get a solidflywheel to replace the duelmass one on the 3l v6?
you can use fly wheel of vectra B V6 its direct swap but you need clutch from vectra too,

yep, I preferred that route and no probs.. and even the clutch kit is 1/3 price of the other here..
I have vectra V6 fly wheel of ebay for 25£ posted and bloke send free clutch with it where was like new :)
Title: Re: solid flywheel
Post by: azza_126 on 21 October 2011, 07:20:54
cheers for the help il get myself a vectra flywheel then :) i just hate duel mass and as a mechanic and knowing how oftern they go wrong when i change the clutch i wanted a soild flywheel to replace the duel mass
Title: Re: solid flywheel
Post by: Marks DTM Calib on 21 October 2011, 08:00:56
Lol, dual mass works well jus not on modern diesels.

No issues with them on the petrol Omegas and have seen them with 300K+ miles on
Title: Re: solid flywheel
Post by: justjohn on 21 October 2011, 08:28:01

No issues with them on the petrol Omegas and have seen them with 300K+ miles on
Just curious, if you had a clutch go at a lower milage, would you replace the DMF as well or take a chance after inspecting it?

Or does it depend on the make of car / engine type?



Title: Re: solid flywheel
Post by: serek on 21 October 2011, 10:08:49

No issues with them on the petrol Omegas and have seen them with 300K+ miles on
Just curious, if you had a clutch go at a lower milage, would you replace the DMF as well or take a chance after inspecting it?

Or does it depend on the make of car / engine type?
you can check condition of DMF and if its ok can replace just clutch.
Title: Re: solid flywheel
Post by: serek on 21 October 2011, 10:13:47
cheers for the help il get myself a vectra flywheel then :) i just hate duel mass and as a mechanic and knowing how oftern they go wrong when i change the clutch i wanted a soild flywheel to replace the duel mass

omega DMF are VERY good not like ones on modern cars, never saw omega with DMF problem so far  :y
Title: Re: solid flywheel
Post by: azza_126 on 21 October 2011, 18:16:41
the only advantage to having the solid one i thought maybe it would be lighter? and iv had lots of problems with mordern ones just dont wanna take the risk but cheers for the advise lads
Title: Re: solid flywheel
Post by: serek on 21 October 2011, 19:26:13
the only advantage to having the solid one i thought maybe it would be lighter? and iv had lots of problems with mordern ones just dont wanna take the risk but cheers for the advise lads
standard fly wheel of vectra its about 15kgs where same as omega DMF

Title: Re: solid flywheel
Post by: Andy B on 21 October 2011, 22:07:07
. ....

omega DMF are VERY good not like ones on modern cars, never saw omega with DMF problem so far  :y

Local dealer had various manual white Omegas in the workshop after Plod had been playing .......  ;)
Title: Re: solid flywheel
Post by: lozzzzzz on 22 October 2011, 08:47:45
I have a courtney 5.6kg jobby on the scimitar build, I've no idea how it feels yet as it doesn't have a prop shaft and many other things, but I can tell you the revs pick up very quickly indeed. 

There is a massive advantage in haveing a light flywheel, you can run through some simple calc (simple if you make some resonable assumptions). 

Assume the majority of the mass of the flywheel to be at 2/3 of the radius to make life easy, so imagine the flywheel to be spinning a large mass at 95mm from its centre. 

We'll work with 1kg to start with.

Multiply this 1kg on the flywheel through the first gear ratio of 3.81, and the final drive ratio of 3.9 (if thats the one you've got) and its like having an extra 14.6 kg strapped to you're wheel at 95mm from the centre for every 1kg on the flywheel. 

You can now equate this to an extra mass in the car by multiplying this mass by the ratio of "mass radius on the flywheel / radius of the wheel". 

So in first gear its like 4.4kg extra weight in the car for every extra kg of mass in the flywheel. 

And if you shave 10kg off with a courtney flywheel its like loosing 43kg off the weight of the car in first gear. 

This lowers to a 24kg reduction in car weight in 2nd gear, and 15kg in thrid. 



I've not done this calculation before, and I seem to have almost convinced myself while writing this that is might not have been worth the extra money :(

I was a little conservative with the assumptions, the majority of the mass is very near the outer edge making it more like 55kg of the weight of the car in 1st. 

hmm.....    I kinda hope I've got something wrong, I was under the impression it made a bigger difference :(

Bummer!
Title: Re: solid flywheel
Post by: albitz on 22 October 2011, 09:07:39
Ive always believed that a lightened flywheel only makes a noticeable difference while the car is in neutral.Once its connected to the transmission,and therefore the weight of the rest of the car,I cant see what difference it can make.
Handy for blipping the throttle on double declutch downchanges I suppose. :-\
Title: Re: solid flywheel
Post by: azza_126 on 22 October 2011, 09:47:30
well i believe any weight off the engine and running gear is always better than no weight as it will always rev up easyer and quicker even if its just a fly wheel as there is less weight to spin up thats also a reason why people use light weight props and have light weight racing forged pistons every little helps even if you only start with the flywheel.
also people use light weight alloys and drive shafts.
i found a light weight flywheel on cortneys website for the 2.5v6 vectra but if what is said is right then that should fit the omega aswell :)
Title: Re: solid flywheel
Post by: albitz on 22 October 2011, 09:58:34
Its a samall reduction in overall weight yes,but an expensive one imo.Lightweight pistons - a different matter.They have to accellerate from bdc to tdc,stop and go back down to bdc many times per second.A small weight reduction will help in that process and put much less stress and strain on the crank and bearings etc.
I may be wrong and am quite willing to be corrected by someone with more technical knowledge than me - which isnt difficult. ::) ;)
Title: Re: solid flywheel
Post by: Andy B on 22 October 2011, 13:57:24
I agree with Albs. All very well spinning an engine up to sillyrpm in a nanosecond if the car is also lightweight, but we're talking 1700 kg of Omega. A lightened flywheel in a car like a Scimitar that you can pick up on your own I reckon will be a different ball game.  :y
Title: Re: solid flywheel
Post by: lozzzzzz on 22 October 2011, 14:39:50
Albs, I see what you're saying about the light wieght pistons, but it won't help the car accelerate any quicker, however, the lighter stonger components will all the max rpm to be raised without stressing the crank like you said, so with different cams they allow more power to be made. 

azza_126, too right, taking mass of rotating components is much better than taking the same mass off the car, its all about the gearing, the engine has to rotate 15 times (in first) for every rotation of the wheel, so any reduction in mass will be be 15 times more effective if its taken away from something spinning at engine speed (in 1st). 

The courtney flywheel definately fits :) you need some different bolts though, part number 90511423.  And the clutch is a bit of a pain as you need to find one with springs (otherwise its really judery to drive).  I used one from some 2.2 something or other, I'm hoping it will stand up to the torque, time will tell. 

Andy, thats the plan :) I think it'll be weighing in at 1200 ish when its all done maybe a tad more, I'll let you'll know. 

(sorry for threadjacking)
Title: Re: solid flywheel
Post by: serek on 22 October 2011, 15:02:03
Albs, I see what you're saying about the light wieght pistons, but it won't help the car accelerate any quicker, however, the lighter stonger components will all the max rpm to be raised without stressing the crank like you said, so with different cams they allow more power to be made. 

azza_126, too right, taking mass of rotating components is much better than taking the same mass off the car, its all about the gearing, the engine has to rotate 15 times (in first) for every rotation of the wheel, so any reduction in mass will be be 15 times more effective if its taken away from something spinning at engine speed (in 1st). 

The courtney flywheel definately fits :) you need some different bolts though, part number 90511423.  And the clutch is a bit of a pain as you need to find one with springs (otherwise its really judery to drive).  I used one from some 2.2 something or other, I'm hoping it will stand up to the torque, time will tell

Andy, thats the plan :) I think it'll be weighing in at 1200 ish when its all done maybe a tad more, I'll let you'll know. 

(sorry for threadjacking)
clutch for fly wheel from courtney its cheap , its standard clutch of vectra b where you can buy on ebay for next to nothing.
but fly wheel from courtney cost near 300£ and on top of that cost of clutch will come round 500 notes ;)
where you can use C20XE flat type fly wheel 6.5kgs from 10£ on ebay ,its possible have this done lot cheapper with same result
Title: Re: solid flywheel
Post by: azza_126 on 22 October 2011, 23:31:52
so does the c20xe flywheel fit the x30xe engine?
Title: Re: solid flywheel
Post by: lozzzzzz on 23 October 2011, 07:42:31
The X30XE has a very odd bolt pattern on the flywheel, its far from symetrical and can only be fitted one way.  And even if the c20xe fits you'll have to do something pretty clever with clutch release as the whole clutch assembly will be closer to the engine with it being a flat flywheel (not 2 inches thick).
Title: Re: solid flywheel
Post by: cem_devecioglu on 23 October 2011, 10:05:17
I have witnessed a bit vibration on cold mornings until the engine heat up.. and a tiny flywheel may increase it, so personally I wouldnt go for x20xe clutch
Title: Re: solid flywheel
Post by: azza_126 on 23 October 2011, 15:48:00
so does the c20xe flywheel fit or not? (sorry im getting a bit confused lol)
Title: Re: solid flywheel
Post by: cem_devecioglu on 23 October 2011, 17:31:50
so does the c20xe flywheel fit or not? (sorry im getting a bit confused lol)

no idea :-\
Title: Re: solid flywheel
Post by: serek on 23 October 2011, 18:05:47
so does the c20xe flywheel fit or not? (sorry im getting a bit confused lol)
fit, will post some photos
Title: Re: solid flywheel
Post by: azza_126 on 23 October 2011, 18:21:55
That's good then does it work? I mean any problems like clutch slipping due to more power in the v6 or bearing not reaching?
Title: Re: solid flywheel
Post by: serek on 23 October 2011, 18:54:49
The X30XE has a very odd bolt pattern on the flywheel, its far from symetrical and can only be fitted one way.  And even if the c20xe fits you'll have to do something pretty clever with clutch release as the whole clutch assembly will be closer to the engine with it being a flat flywheel (not 2 inches thick).

that what sort space problem 
(http://i845.photobucket.com/albums/ab19/doubledecka2/2011_02240052.jpg)

got it fitted C20xe flywheel and clutch with 228mm clutch plate in to my mate 3.0 few weeks ago
hi done over 2K miles since.
Title: Re: solid flywheel
Post by: serek on 23 October 2011, 18:57:55
I have witnessed a bit vibration on cold mornings until the engine heat up.. and a tiny flywheel may increase it, so personally I wouldnt go for x20xe clutch
cant feal any on his car, any differents comper to DMF
Title: Re: solid flywheel
Post by: cem_devecioglu on 23 October 2011, 19:31:49
I have witnessed a bit vibration on cold mornings until the engine heat up.. and a tiny flywheel may increase it, so personally I wouldnt go for x20xe clutch
cant feal any on his car, any differents comper to DMF

not very sure though, it might be shaft dampers also :-\
Title: Re: solid flywheel
Post by: serek on 23 October 2011, 19:40:32
I have witnessed a bit vibration on cold mornings until the engine heat up.. and a tiny flywheel may increase it, so personally I wouldnt go for x20xe clutch
cant feal any on his car, any differents comper to DMF

not very sure though, it might be shaft dampers also :-\
soon as I get fetted to my car I will let you know results :y
Title: Re: solid flywheel
Post by: azza_126 on 23 October 2011, 20:44:47
So where did you get the spacer from and how much did it cost?
Title: Re: solid flywheel
Post by: serek on 23 October 2011, 22:06:29
So where did you get the spacer from and how much did it cost?
there is bloke on manta forum who sale them for just under 30£ posted :y

Title: Re: solid flywheel
Post by: 2woody on 24 October 2011, 14:08:07
I have a courtney 5.6kg jobby on the scimitar build, I've no idea how it feels yet as it doesn't have a prop shaft and many other things, but I can tell you the revs pick up very quickly indeed. 

There is a massive advantage in haveing a light flywheel, you can run through some simple calc (simple if you make some resonable assumptions). 

Assume the majority of the mass of the flywheel to be at 2/3 of the radius to make life easy, so imagine the flywheel to be spinning a large mass at 95mm from its centre. 

We'll work with 1kg to start with.

Multiply this 1kg on the flywheel through the first gear ratio of 3.81, and the final drive ratio of 3.9 (if thats the one you've got) and its like having an extra 14.6 kg strapped to you're wheel at 95mm from the centre for every 1kg on the flywheel. 

You can now equate this to an extra mass in the car by multiplying this mass by the ratio of "mass radius on the flywheel / radius of the wheel". 

So in first gear its like 4.4kg extra weight in the car for every extra kg of mass in the flywheel. 

And if you shave 10kg off with a courtney flywheel its like loosing 43kg off the weight of the car in first gear. 

This lowers to a 24kg reduction in car weight in 2nd gear, and 15kg in thrid. 



I've not done this calculation before, and I seem to have almost convinced myself while writing this that is might not have been worth the extra money :(

I was a little conservative with the assumptions, the majority of the mass is very near the outer edge making it more like 55kg of the weight of the car in 1st. 

hmm.....    I kinda hope I've got something wrong, I was under the impression it made a bigger difference :(

Bummer!

your calculation is basically sound. It's definitely a worthwhile mod to do.

think about it, reducing the flywheel weight by 1 kg has the same affect as reducing the car weight by 50kg or so. So for a typical 10kg lighter flywheel, then you'll accelerate as if the car weighed a third less.

I've recently fitted an aluminium flywheel to the Holden. the 0-80 time in 2nd reduced by 4 seconds.

Obviously the effect is reduced in the higher ratios
Title: Re: solid flywheel
Post by: Kevin Wood on 24 October 2011, 14:49:17
Another point about light flywheels is that the engine responds faster to the throttle and slows quicker when you come off it, so a quick blip of the throttle is all you need on a downchange instead of a blaaaarrrrrrp with a heavy flywheel. ;)

Changing up, the engine loses revs much quicker so you can make a smooth change from maximum revs quicker and without the clutch getting punishment from an engine that's still doing 6500 RPM when you engage the next gear.

Downside is that you'll have less stored momentum in the engine from idle so it'll be a bit less forgiving in traffic and you need to get launches more accurate as it's easier to stall it.

It made a noticeable difference on all counts fitting a light flywheel to my Westfield (18kg->5.5kg) but that is a very light car compared to an Omega.
Title: Re: solid flywheel
Post by: Marks DTM Calib on 24 October 2011, 14:54:38
Trouble is that you need to know the inertia of the flywheels before and after lightning as its not the weight that is the key factor in calculating any gains. In theory you could make a heavier flywheel with less inertia!





Title: Re: solid flywheel
Post by: 2woody on 24 October 2011, 15:05:02
ever tried calculating the rotational inertia of something ?
Title: Re: solid flywheel
Post by: Marks DTM Calib on 24 October 2011, 16:36:26
Never calculated it, have measure it a few times though  :y

The key point is that lighter is only better if done properly.  :y