[Mk2] [Turbo] Modifying/lightening the stock flywheel

[moscoworbust]

Hi,

Has anyone modified the stock flywheel?

As in lightened it?

My old car had a lightened flywheel and my new one doesn't and it is fairly disappointing not being able to rev it up fast.

So, the ready made ones are 250-350 quid.

i.e. http://www.camskill.co.uk/m5b11s608p840 ... SW20/RS_GB

I was just looking to trim some off the stock flywheel, drill some holes in it. The ready made ones are made out of a different material so don't expect the same weight saving.

Although I guess after paying for balancing it wouldn't be that cheap anyway.

Just nicer to do things yourself.

[ashley]

If you're going to get the stock flywheel lightened please don't do it yourself, get a quality machine shop to do it for you- and they will balance it at the same time.

[bobhatton]

Hi,

Has anyone modified the stock flywheel?

As in lightened it?

My old car had a lightened flywheel and my new one doesn't and it is fairly disappointing not being able to rev it up fast.

So, the ready made ones are 250-350 quid.

i.e. http://www.camskill.co.uk/m5b11s608p840 ... SW20/RS_GB

I was just looking to trim some off the stock flywheel, drill some holes in it. The ready made ones are made out of a different material so don't expect the same weight saving.

Although I guess after paying for balancing it wouldn't be that cheap anyway.

Just nicer to do things yourself.

Never fit a lighter flywheel. It will not give any performance increase and will knock out the main bearings and could even snap the crankshaft.

[moscoworbust]

If you're going to get the stock flywheel lightened please don't do it yourself, get a quality machine shop to do it for you- and they will balance it at the same time.

Ashley, just because you are not capable of something you shouldn't assume someone else isn't. Replying to each topic with an instantly derogatory and depressing attitude is not helpful at all.

Never fit a lighter flywheel. It will not give any performance increase and will knock out the main bearings and could even snap the crankshaft.

Have you actually seen this happen? I had a lightened flywheel on my old mr2 gts and the crankshaft did not snap and the bearings did not get knocked out.

Have you heard of the concept of MOI?

[bobhatton]

If you're going to get the stock flywheel lightened please don't do it yourself, get a quality machine shop to do it for you- and they will balance it at the same time.

Ashley, just because you are not capable of something you shouldn't assume someone else isn't. Replying to each topic with an instantly derogatory and depressing attitude is not helpful at all.

Never fit a lighter flywheel. It will not give any performance increase and will knock out the main bearings and could even snap the crankshaft.

Have you actually seen this happen? I had a lightened flywheel on my old mr2 gts and the crankshaft did not snap and the bearings did not get knocked out.

Have you heard of the concept of MOI?

We had a crank cut up to check the counter weights and they are only 50% of the weight they should be. The weight of the flywheel and front pulley help to stop the crank bending.

MOI, no do not know that

[Moo]

I believe the OP is referring to Moment of Inertia.

http://hyperphysics.phy-astr.gsu.edu/hbase/mi.html#mi

[ashley]

Ashley, just because you are not capable of something you shouldn't assume someone else isn't. Replying to each topic with an instantly derogatory and depressing attitude is not helpful at all.

Apologies if it came across that way- I absolutely was not attempting to be derogatory or depressing!

I assumed that if you are not capable of balancing your flywheel with the tools you have, that you would not be capable of lightening it safely either. I had images of you sticking your flywheel on a laithe and skimming it, then putting it in a drill press and making holes...all of which scared me having seen the damage a disintegrating flywheel can do in the past.

Sorry- certainly wasn't trying to be down on your abilities, just concerned for your safety...I will bow out now...

[bobhatton]

I believe the OP is referring to Moment of Inertia.

http://hyperphysics.phy-astr.gsu.edu/hbase/mi.html#mi

Oh right, and so how will that make the car go faster?

[AManInDandism]

Oh right, and so how will that make the car go faster?

I believe OP meant faster acceleration.

[Moo]

I believe the OP is referring to Moment of Inertia.

http://hyperphysics.phy-astr.gsu.edu/hbase/mi.html#mi

Oh right, and so how will that make the car go faster?

Nobody is saying it would.

[bobhatton]

I believe the OP is referring to Moment of Inertia.

http://hyperphysics.phy-astr.gsu.edu/hbase/mi.html#mi

Oh right, and so how will that make the car go faster?

Who said it would?

Ok, so what is the point in doing it?

[AManInDandism]

Oh right, and so how will that make the car go faster?

Who said it would?

Ok, so what is the point in doing it?

Not sure if serious...

[Moo]

Oh right, and so how will that make the car go faster?

Who said it would?

Ok, so what is the point in doing it?

To give faster acceleration by reducing rotational mass is my understanding. As to whether it's a good idea or not is something I don't have an opinion on.

OP - sorry for the hijack.

[GreddyMR2]

Hi,

Has anyone modified the stock flywheel?

As in lightened it?

My old car had a lightened flywheel and my new one doesn't and it is fairly disappointing not being able to rev it up fast.

So, the ready made ones are 250-350 quid.

i.e. http://www.camskill.co.uk/m5b11s608p840 ... SW20/RS_GB

I was just looking to trim some off the stock flywheel, drill some holes in it. The ready made ones are made out of a different material so don't expect the same weight saving.

Although I guess after paying for balancing it wouldn't be that cheap anyway.

Just nicer to do things yourself.

Never fit a lighter flywheel. It will not give any performance increase and will knock out the main bearings and could even snap the crankshaft.

I am using JUN lightened flywheel with ceramic clutch with no problems. Seen lots of autocross and track days.

[greeny]

Never fit a lighter flywheel. It will not give any performance increase and will knock out the main bearings and could even snap the crankshaft.

You do talk some b0ll0cks sometimes

[sparki]

Findanza one here for at least 8k miles, no problems so far.

I had one on my old almera. That one was a night and Day difference, Not so much on the MR2.

[bobhatton]

Never fit a lighter flywheel. It will not give any performance increase and will knock out the main bearings and could even snap the crankshaft.

You do talk some b0ll0cks sometimes

All I do is give the facts.
If anyone does not have the intelligence to understand the facts there is nothing I can do to help.

http://www.imoc.co.uk/forums/viewtopic. ... oken+crank

[RyanRs]

Never fit a lighter flywheel. It will not give any performance increase and will knock out the main bearings and could even snap the crankshaft.

Remember simple physics. F=ma Force = Mass x acceleration. If we rearange this formula to focus on Acceleration then it would be a=F/m So therefore to increase the rate of acceleration we have to either increase the force or decrease the Mass!

Ergo..

If we have a flywheel with a mass of 20kg we want to accelerate it at a rate of 10m/s we would need to input a force of 200 Kgm/s^2 (200 Newtons or 0.27bhp ) to achieve this. Now, if we lighten the flywheel to 10kg we would only need to input a force of 100N so 50% less power is required.

So.. to sum up. a flywheel that weighs half of another flywheel will require half the amount of force to make it move. this therefore requires less Power to produce the force and hence more available power for use in acceleration of the entire car.

[greeny]

Never fit a lighter flywheel. It will not give any performance increase and will knock out the main bearings and could even snap the crankshaft.

You do talk some b0ll0cks sometimes

All I do is give the facts.
If anyone does not have the intelligence to understand the facts there is nothing I can do to help.

http://www.imoc.co.uk/forums/viewtopic. ... oken+crank

So if someone doesn't agree with your opinion, which you then presume to be fact, they lack intelligence?

Meanwhile in the real world......

It's not just about the weight of the flywheel/clutch. You could have 2 exact same weight flywheel's which could both have very different characteristics and impose different stresses on the crank. It's all about where the weight is/isn't on the flywheel relevant to the centre of the crank.

Just out of interest.... which flywheel and clutch are you planning to use on your 900+hp 3sgte you're building?

I'm presuming it's going to be a stock flywheel and clutch, seeing as you can't/shouldn't mess with toyota's design?