lighting balanced flywheel ?
05-02-2009, 08:46 PM
#4
Regular Contributor
iTrader: (1)
Join Date: Feb 2008
Location: under the bonnet somewhere in Dewsbury
Posts: 230
Likes: 0
Received 0 Likes
on
0 Posts
i agree with the above comments,i had one in my old xr3i that had alot of work done to the engine,and the flywheel was too light to balance at normal tick over.
06-02-2009, 12:06 PM
#6
That's not true, what you will lose/gain (however you want to look at it) is momentum.
Just as a light flywheel will allow the engine to rev faster, it will also make it lose revs faster when you come off the throttle, meaning that you may fall out of the powerband on gearchanges.
Mine has run a marginally lightened flywheel for years and to no ill effect. I have never been able to measure any gain, but its like anything, its hard to prove/disprove.
06-02-2009, 12:09 PM
#7
Too many posts.. I need a life!!
Join Date: Aug 2008
Location: West Mids
Posts: 804
Likes: 0
Received 0 Likes
on
0 Posts
Its a known fact they decrease the torque output and cause the revs to drop quicker on a turbo which is exactly what you dont want as it will increase the time it take to reach full boost again through the gears.
It all comes down to what the car is going to be used for, if its a N/A CVH used for circuit racing then lighter would be ideal in this situation as you require a snappier response on the pedal
It all comes down to what the car is going to be used for, if its a N/A CVH used for circuit racing then lighter would be ideal in this situation as you require a snappier response on the pedal
Last edited by B16CVH; 06-02-2009 at 12:11 PM.
Trending Topics
06-02-2009, 12:25 PM
#8
I'm sorry, but I'd have to see evidence before I believed that.
My opinion is that a light flywheel doesn't affect the amount of torque an engine produces. OK, so the way that torque is delivered is changed due to the car dropping off RPM's faster versus your own ability to change gear fast enough
The flywheel is driven by the engine, so if anything I'd have thought power to the wheels would increase, just in the same way as improving other transmission components would have that effect.
My opinion is that a light flywheel doesn't affect the amount of torque an engine produces. OK, so the way that torque is delivered is changed due to the car dropping off RPM's faster versus your own ability to change gear fast enough
The flywheel is driven by the engine, so if anything I'd have thought power to the wheels would increase, just in the same way as improving other transmission components would have that effect.
06-02-2009, 12:37 PM
#9
Too many posts.. I need a life!!
Join Date: Aug 2008
Location: West Mids
Posts: 804
Likes: 0
Received 0 Likes
on
0 Posts
Yes the engine drives the flywheel but also if you think about it the flywheel also drives the crank through the inertia of the flywheel rotating. In a crude way the flywheel "helps" the engine along and this is why it increases torque. I agree that lightening only by a small amount probably wont make alot of difference but shaving kgs of the rotating weight certainly will.
06-02-2009, 12:45 PM
#10
Too many posts.. I need a life!!
iTrader: (2)
Join Date: Jun 2004
Location: leicester
Posts: 884
Likes: 0
Received 0 Likes
on
0 Posts
I'm sorry, but I'd have to see evidence before I believed that.
My opinion is that a light flywheel doesn't affect the amount of torque an engine produces. OK, so the way that torque is delivered is changed due to the car dropping off RPM's faster versus your own ability to change gear fast enough
The flywheel is driven by the engine, so if anything I'd have thought power to the wheels would increase, just in the same way as improving other transmission components would have that effect.
My opinion is that a light flywheel doesn't affect the amount of torque an engine produces. OK, so the way that torque is delivered is changed due to the car dropping off RPM's faster versus your own ability to change gear fast enough
The flywheel is driven by the engine, so if anything I'd have thought power to the wheels would increase, just in the same way as improving other transmission components would have that effect.
im laughin at this point, an automatic car has no real flywheel, just a ring gear for the starter..............
does this mean it has less or no torque?? B19 CVH
NO
06-02-2009, 12:48 PM
#11
Too many posts.. I need a life!!
iTrader: (2)
Join Date: Jun 2004
Location: leicester
Posts: 884
Likes: 0
Received 0 Likes
on
0 Posts
by the way i do realise what back ground of car modification christian comes from, and his thinking supports mine before anyone thinks im slating him
im only writing this as im at home ill and bored
im only writing this as im at home ill and bored
06-02-2009, 03:45 PM
#12
Lose torque??!!
That's not true, what you will lose/gain (however you want to look at it) is momentum.
Just as a light flywheel will allow the engine to rev faster, it will also make it lose revs faster when you come off the throttle, meaning that you may fall out of the powerband on gearchanges.
Mine has run a marginally lightened flywheel for years and to no ill effect. I have never been able to measure any gain, but its like anything, its hard to prove/disprove.
That's not true, what you will lose/gain (however you want to look at it) is momentum.
Just as a light flywheel will allow the engine to rev faster, it will also make it lose revs faster when you come off the throttle, meaning that you may fall out of the powerband on gearchanges.
Mine has run a marginally lightened flywheel for years and to no ill effect. I have never been able to measure any gain, but its like anything, its hard to prove/disprove.
maybe i'm completely wrong, to be honest i havent looked into it.
i personally would lighten a flywheel, especially as i wouldnt know how much kg to take off. the more you take off the less solid it becomes and more prone to stress fractures
i've seen cracked flywheels before and not something i would want to experience on any car.....a flywheel breaking up at 6000 or what ever RPM is not my idea of fun
Matt
06-02-2009, 04:02 PM
#15
Too many posts.. I need a life!!
iTrader: (2)
Join Date: Jun 2004
Location: leicester
Posts: 884
Likes: 0
Received 0 Likes
on
0 Posts
no im fine, such a fine example of pfs loverly audience
ive seen how the pf regulars kill the jews
ive been college
work in the trade
and support ppl with knowledge
i even work at ford
not not like the ppl who own a haynes manual and think they can fix everything
06-02-2009, 04:04 PM
#16
Too many posts.. I need a life!!
iTrader: (2)
Join Date: Jun 2004
Location: leicester
Posts: 884
Likes: 0
Received 0 Likes
on
0 Posts
i also like your double post
is this a pf school boy error so ppl think your a valued member of their fantacy land pf because you have a high post count
06-02-2009, 04:55 PM
#17
Too many posts.. I need a life!!
Join Date: Aug 2008
Location: West Mids
Posts: 804
Likes: 0
Received 0 Likes
on
0 Posts
A few flywheel quotes:
"I had one in my old Cav V6. the most noticable thing I found was lower fuel economy on long runs. The thristy V6 round town was capable of high 35-40mpg on a run. This dropped to 30-35mpg after having the flywheel lightened as the stored energy in the mass of the wheel wasnt turning the engine "for free". Round town I didnt notice any improvement except in the drivabilty, much easier to get going and a much nicer driver."
https://passionford.com/forum/general-car-related-discussion/246191-what-advantages-disadvantages-if-lightened-flywheels.html#post3392763
"I had one in my old Cav V6. the most noticable thing I found was lower fuel economy on long runs. The thristy V6 round town was capable of high 35-40mpg on a run. This dropped to 30-35mpg after having the flywheel lightened as the stored energy in the mass of the wheel wasnt turning the engine "for free". Round town I didnt notice any improvement except in the drivabilty, much easier to get going and a much nicer driver."
https://passionford.com/forum/general-car-related-discussion/246191-what-advantages-disadvantages-if-lightened-flywheels.html#post3392763
06-02-2009, 06:21 PM
#18
A few flywheel quotes:
"I had one in my old Cav V6. the most noticable thing I found was lower fuel economy on long runs. The thristy V6 round town was capable of high 35-40mpg on a run. This dropped to 30-35mpg after having the flywheel lightened as the stored energy in the mass of the wheel wasnt turning the engine "for free". Round town I didnt notice any improvement except in the drivabilty, much easier to get going and a much nicer driver."
https://passionford.com/forum/showthread.php?p=3392763
"I had one in my old Cav V6. the most noticable thing I found was lower fuel economy on long runs. The thristy V6 round town was capable of high 35-40mpg on a run. This dropped to 30-35mpg after having the flywheel lightened as the stored energy in the mass of the wheel wasnt turning the engine "for free". Round town I didnt notice any improvement except in the drivabilty, much easier to get going and a much nicer driver."
https://passionford.com/forum/showthread.php?p=3392763
It's a bit arse-about-face in my logical eyes. Torque is produced BEFORE the flywheel and if anything, the flywheel being lighter will help the engine be more efficient.
Agreed that you have to know what you are doing and going too light will have nasty side-effects. Also, whether or not you notice the difference may be questionable too, but that's no different to many other mods (like knife-edging cranks etc).
My 1600CVH makes 300lb/ft with the lightened Flywheel on it. I've had that fitted since around 2004, so any results the car has achieved have been with it. How many other 1600 CVH Turbo's have done 300lb/ft?
06-02-2009, 08:47 PM
#22
To put things very simply......
Torque is a measurement of Force applied in rotation, what determines this force (and is it's point of origin) in our engines is the size of the explosion in the chambers not the weight of the fly.
Changing the weight of the flywheel just adds or subtracts load/drag applied to that Force.
So....
Lighter Fly means less load and allows it to accelerate faster, and in theory more power and torque will be available at the wheels.
Heavier Fly means more load and will slow down acceleration, and in theory restrict power and torque available at the wheels.
But... lightening the Fly will loose you momentum, and so things like hill climbs, standing starts etc.. will require more RPM's than before.
This is worth a read http://www.torquecars.com/tuning/fly...lightening.php
Knife edging your crank has a similair effect but also reduces some of the counter weights vibration dampening, and so really the entire engine should be rebalanced after doing this.
Torque is a measurement of Force applied in rotation, what determines this force (and is it's point of origin) in our engines is the size of the explosion in the chambers not the weight of the fly.
Changing the weight of the flywheel just adds or subtracts load/drag applied to that Force.
So....
Lighter Fly means less load and allows it to accelerate faster, and in theory more power and torque will be available at the wheels.
Heavier Fly means more load and will slow down acceleration, and in theory restrict power and torque available at the wheels.
But... lightening the Fly will loose you momentum, and so things like hill climbs, standing starts etc.. will require more RPM's than before.
This is worth a read http://www.torquecars.com/tuning/fly...lightening.php
Knife edging your crank has a similair effect but also reduces some of the counter weights vibration dampening, and so really the entire engine should be rebalanced after doing this.
Last edited by Karlos G; 06-02-2009 at 09:07 PM.
06-02-2009, 08:48 PM
#23
focus rs 1672
30-10-2018, 11:34 PM
#27
Virgin
Join Date: Sep 2017
Location: Tenerife
Posts: 4
Likes: 0
Received 0 Likes
on
0 Posts
To put things very simply......
Torque is a measurement of Force applied in rotation, what determines this force (and is it's point of origin) in our engines is the size of the explosion in the chambers not the weight of the fly.
Changing the weight of the flywheel just adds or subtracts load/drag applied to that Force.
So....
Lighter Fly means less load and allows it to accelerate faster, and in theory more power and torque will be available at the wheels.
Heavier Fly means more load and will slow down acceleration, and in theory restrict power and torque available at the wheels.
But... lightening the Fly will loose you momentum, and so things like hill climbs, standing starts etc.. will require more RPM's than before.
This is worth a read http://www.torquecars.com/tuning/fly...lightening.php
Knife edging your crank has a similair effect but also reduces some of the counter weights vibration dampening, and so really the entire engine should be rebalanced after doing this.
Torque is a measurement of Force applied in rotation, what determines this force (and is it's point of origin) in our engines is the size of the explosion in the chambers not the weight of the fly.
Changing the weight of the flywheel just adds or subtracts load/drag applied to that Force.
So....
Lighter Fly means less load and allows it to accelerate faster, and in theory more power and torque will be available at the wheels.
Heavier Fly means more load and will slow down acceleration, and in theory restrict power and torque available at the wheels.
But... lightening the Fly will loose you momentum, and so things like hill climbs, standing starts etc.. will require more RPM's than before.
This is worth a read http://www.torquecars.com/tuning/fly...lightening.php
Knife edging your crank has a similair effect but also reduces some of the counter weights vibration dampening, and so really the entire engine should be rebalanced after doing this.
Thread
Thread Starter
Forum
Replies
Last Post
The Enigma
Ford Sierra/Sapphire/RS500 Cosworth
2
12-09-2015 10:12 PM
