Light weight fly wheels ????

[AIROCOBRA]

LIGHT WEIGHT FLY WHEELS

What are the pro & cons of using a light weight fly wheel on a 4age 16v ???

Engine is in a sprinter ae86 --- used for hill climbs . motorkhana and the odd sprint. Slightly warm engine say about 90kw at rear wheels.
Will putting a fly wheel that is half the normal weight help or hinder ????

[-ollie-]

As far as i know know it will help, otherwise why on earth would all these brands make them?
Lighter flywheel put less load on the engine, therefore it can rev much more 'freely'

[.ady]

compared to a stock fly wheel the lighter you go the less torque you get?

[Slimer86]

Lighter for hillclimb orientated vehicle (read street), not recommended normally, but motorsport you will be wringing its neck anyway, so highly recommended.
I run a Toda 3.7kg (Measured to be 3.65kg) flywheel on a stock silvertop 20V and think its one of the best mods I did to it. Suits me. Fantastic on downhill stretches.
Overall weight of the assembly was 7.5kg, which turned out to be the similar weight of a stock small port flywheel.
On the street, you may have to downshift to climb hills.

Yes, less inertial mass, and in turn angular torque.

[Rice86]

must get light weight flywheel

[Robo86]

Good mod, did it myself on old 4age, made a good difference!

AJPS^^ sells some nice ones.

[Sam-Q]

you dont lose torque just inertial energy buildup ability.

I went from the 6.9kg silvertop flywheel to the 5.9kg blacktop flywheel, the figures dont tell the full story though as that 1kg is taken off the very outside so the two are quite different. Strangely enough I didn't notice much of a differece driving around but I did when taking off, I found it very easy to stall. This problem was tottaly taken care of with my aftermarket ecu though. now that my engine is running nice I should change it back with a quick gearbox swap at the same time to see how it is.

[stuartgze]

i run a 3.7 kg one from dave. it's pretty good can't really fault it. my old one was 7.4 kg. It's a bit more responsive but it's didn't change my life. Might be different on a N/A car. it's pretty cheap too so it's well worth it.

[Sam-Q]

hey I have thought for a while wouldnt a drift car be best off with a heavy arse flywheel?

[bigm]

heavier flywheel means more rotational force keeping the wheels turning??

is that what u were thinking sam?

[Sam-Q]

thats exactly what I have been thinking

[bigm]

i agree mate,

i ran a heavier flywheel (turbo sr on DE motor) for that reason..

[Sam-Q]

oh so another one of my crazy ideas is actualy right

[Hen may possibly be a nut]

Light flywheels are great.

The only downside (apart from stalling more often and looking a little silly) is that, as said, they don't store as much inertia, so clutch kicks are less effective. A friend fitted a bling, superlight flywheel to his Silvia once, then removed it after one drift day since he couldn't kick it.

Hen

[keiichi]

less power-loss to the ground, with a lighter one as someone probobly already said, so therefor increasing your rwkw

[bigm]

haha duno if its right sam, maybe im just as crazy as u
lol

but im also with hen with the clutch kick, mine were a breeze!

[Frak]

The flywheel is an energy storage device, the heavier it is the more energy it can store, the reason for this is to SMOOTHLY KEEP THE ENGINE SPINNING OVER UNTIL IT'S NEXT POWER PULSE. A heavy flywheel can store much energy therefore is harder to slow down, think of a very heavy mass turning at 6000rpm, it will take either a long time to slow down or a lot of energy to stop it.

a light flywheel can not store much energy, this is one reason why it is easier to stall an engine equipped with a light flywheel, also with a light flywheel, you will find at lower rpm's the rpm the engine will happily and smoothly spin over at whilst driving will be higher the lighter the flywheel is, example, with original flywheel you may find that the engine will happily cruise at 60km/h in top gear, whilst with a light flywheel you may have to go down a gear and get the rpm up to maintain 60km/h smoothly. This is due to the reduced amount of stored energy, obviously at higher rpm's this is not as much of a problem unless the engine is very low torque.

manufacturers put heavy flywheels on to smooth out an engine across the rev range, most cars that are used by the 'average punter' don't see the rpm's we would use ;), not only is it a storage device but also a damper of torque fluctuations. With a very light flywheel you may(or may not) feel these fluctuations as a light surge as the crank is accelerating/deccelerating with each power pulse, obviously on the power pulse the instantaneous acceleration of the crank will increase. A heavier flywheel will dampen this.

They do not rob torque per se. If an engine is generating 150ftlb of torque, regardless of the weight of the flywheel, it's still generating 150ftlb of torque.

A lighter flywheel will allow the engine to accelerate quicker making the car faster, it will also allow it to decelerate faster which is good during braking whilst at a race track.

having said that, I am a fan of the lightest possible flywheel you can get your hands on. Learn not to stall it, use a lower gear and all will be fine, the increase in engine response is definately worth it, I have been using a toda ultra light for many years and it's a worthwhile addition.

This is a flywheel I got for my 4age earlier this year and weighs a tasty 2.4kg
http://img38.imageshack.us/img38/1900/der99649img600x45012381.jpg (http://img38.imageshack.us/i/der99649img600x45012381.jpg/)

In bikes it is quite common in racing to actually use a heavier flywheel, the lighter ones allow the engine to accelerate too quick and generate wheel spin, my RC45 Honda is equipped with a HRC 8hr endurance AGC(alternator) this also incorporates the flywheel, which is heavier for endurance racing to make the bike easier to ride.

I'm sure there is more, others will add, how about pics of ya flywheels......Karl keep it clean ;)

[Vance]

Frak, you are awesome

[ke70dave]

hey frak cool post.

that flywheel you posted.

is that designed for a multi plate clutch? and being multi plate there would be more weight in the clutch setup? thus the rotating mass isnt reduced as much as we think?

(ie uber light flywheel + uber heavy clutch)

[Frak]

Thanks Dave, it's using an AP twin plate, REMEMBER though the mass is at the centre of the flywheel where centifugal forces aren't as prevalent as at the outer edge of the flywheel...if that makes sense. The closer you keep the mass to the centre of the crankshaft the LESS effect it has. Also the clutches are very small diameter each clutch is 140mm in diameter as opposed to either 200mm or 212mm of a usual 4age clutch plate.

As Sam mentioned above when he swapped from an AE101 flywheel to an AE111 flywheel, even tho there wasn't too much difference in mass the AE111 has LESS mass at the outer edge.

SAM, FYI the AE111 looks very similar to what HKS use to pedal, maybe Toyota looked at what the aftermarket where doing?

[Sam-Q]

legendary as usual Frak, the lightest flywheel clutch combo that I have ever heard of used a flexplate and then a small diamater friction surface bolted infront to support a multi-pack arangement. Not that dis-simular from the F1 setups. Reminds me of a story I read ages ago about guys racing on the salf flats, they de-stroked a 4age down to a 1L and they found they just couldnt take off the line without stalling it no matter what they did. The recripricating weight was so low combined with the other factors such as the tall gearing and everything else high rev suited just stopped them from moving.

[Sherlock]

This is my old one:
http://www.ae86drivingclub.com.au/dcimages/0/25344.jpg

The one above was on my AE71. That's now sold and gone but it was awesome. I bought a second one (TRD this time) which will hopefully be as good :).

[Sam-Q]

SAM, FYI the AE111 looks very similar to what HKS use to pedal, maybe Toyota looked at what the aftermarket where doing?

if they did that I would find that really amusing

[Frak]

Just looking through the Toda catalog, in the flywheel section it has a little techincal info. It compares a standard 4age flywheel to a Toda ultra light.

std weight 7.7kg
toda 3.7kg

Toda's chromoly wheel is 48% of the weight of the standard flywheel and 42%
inertia.

standard inertia 0.79kg.cm.S^2 to 0.33kg.cm.S^2

a bit of their hype,
Along with our racing experience we now use CAD soild modeling workstations to further reduce stress and to improve weight distribution and inertia.

BTW I love toda stuff :)

[ke70dave]

legendary as usual Frak, the lightest flywheel clutch combo that I have ever heard of used a flexplate and then a small diamater friction surface bolted infront to support a multi-pack arangement. Not that dis-simular from the F1 setups. Reminds me of a story I read ages ago about guys racing on the salf flats, they de-stroked a 4age down to a 1L and they found they just couldnt take off the line without stalling it no matter what they did. The recripricating weight was so low combined with the other factors such as the tall gearing and everything else high rev suited just stopped them from moving.

that the mr2? some sort of highschool/college project? think i read the same thing. cool read.

as for your post above, yer i understand what your saying.

good ol' moment of inertia.

i didn't realise that multi plate clutches had a smaller contact surface. makes sense though, considering you have more than one.

[Frak]

legendary as usual Frak, the lightest flywheel clutch combo that I have ever heard of used a flexplate and then a small diamater friction surface bolted infront to support a multi-pack arangement. Not that dis-simular from the F1 setups. Reminds me of a story I read ages ago about guys racing on the salf flats, they de-stroked a 4age down to a 1L and they found they just couldnt take off the line without stalling it no matter what they did. The recripricating weight was so low combined with the other factors such as the tall gearing and everything else high rev suited just stopped them from moving.


Funny you should mention that Sam, a friend of mine races an IPRA, his 'flywheel' is a flex plate with a chromoly friction surface bolted to it and using a tilton twin plater.

[Frak]

This is my old one:
http://www.ae86drivingclub.com.au/dcimages/0/25344.jpg

The one above was on my AE71. That's now sold and gone but it was awesome. I bought a second one (TRD this time) which will hopefully be as good :).


Sherlock, this looks like a Toda ultra light?

[Sam-Q]

Dave: yeah the MR2 and I agree I thought it was a great read, particularly about the competition being in disbeleif. With the multiplates see if you can find a pic of an F1 setup, you will be amazed. They are motived by an additional reason though and thats engine height; their engines are moutned so low the flywheel would probably be the lowest point if it wasnt so damn small in diameter.

frak: sounds beasty, how does he find it?

[ke70dave]

i assume your talking about something like this

http://lh5.ggpht.com/_syq-Tcp5Jc4/R47FAqaASpI/AAAAAAAACuE/hcG856g0wo4/IMG_1994.jpg

have you seen the topgear episode when hammond tries to drive the F1 car? with the anti-stall system?

ok this is getting a bit off topic...

[Sherlock]

Sherlock, this looks like a Toda ultra light?

It is, 3.7kg. So good. :heart: TODA.

[Frak]

frak: sounds beasty, how does he find it?

lol, how does he find it, let's just say his starts(turbo SR20) are either huge wheel spin or huge bog ;) but then once up and running all good.

[Sam-Q]

hmm predictable

anyway I found a juicy pic for you guys:

http://www.ffcc.asn.au/photos/BMW_E41-4_Crank_Drive.jpg


http://www.ffcc.asn.au/Pages/bmw_v10_f1_engine_crank.htm

[ke70dave]

that is so cool. to me it almost looks like a photoshop, since its so "not normal". i love it.

any idea on the stroke/bore ratio on that thing? looks like its got a tiny stroke? and a massive bore...

edit, wiki sais: The stroke of a Formula One engine is approximately 39.7 mm (1.563 in), less than half as long as the bore is wide (98.0 mm)

incredible!

[Sam-Q]

I was under the impression they had a 100mm bore and a 24mm stroke, but that may have been for their old V12's

[Frak]

I was under the impression they had a 100mm bore and a 24mm stroke, but that may have been for their old V12's

OMG 24mm stroke, talk about keeping piston speeds down!

[pope]

Yet to install but i just had my stock 3tc flywheel machined down and balanced.

They took a little material off at 1.
http://www.ae86drivingclub.com.au/dcimages/6/0/1/25357.jpg
Then a fair amount at 2.
http://www.ae86drivingclub.com.au/dcimages/6/0/1/25358.jpg

Cost me $130 which included drilling and tapping some holes to fit a Holden pressure plate, lightening and then balancing.

[sundee]

If anyone wants one ive got one. its 3.8 kg suit small port block. PM me

[AIROCOBRA]

Thanks to all the responders ( specially FRAK !!) Great info ----- prompted me to buy a 4.2 kg F/wheel from the USA . ON SPECIAL !!! EBAY USA , down from $475 us ( If you believe the recommended retail ???? ) to $169 us , but with AUST dollar at .90 cent , a good buy I hope . Postage was $99 us . So for about $300 AUS landed still worth while I think. Think I got the last one they had list for 4age AE86 , but I am sure more will be posted .

[Sam-Q]

got a link

[AIROCOBRA]

Here is a link to the store --- http://stores.shop.ebay.com/gripforce-clutches__W0QQ_armrsZ1 .

Also note I got mixed up with the retail price of another brand .

Plus item discription ----


F1 Racing Lightweight Chromoly Flywheels are made from 4140 one-piece billet chromoly steel. They are specifically designed to reduce weight and inertia for better engine response. Most incorporate special design features to enhance the air flow to improve the cooling of the clutch. The ring gear teeth are milled onto the flywheel unlike an aluminum flywheel where the ring gear is pressed onto the flywheel which has the possibility of separating from the flywheel. All F1 Racing Chromoly flywheels have passed engineering tests to 12,000 rpm. After professionally installed the flywheel requires a 500 mile break-in period.

* Ultra heavy-duty and weighs only 10 lbs (stock flywheel weighs 19 lbs)
* Meets or exceeds SFI 1.1 specification
* Made from 4140 forged chromoly steel (2X stronger than billet steel)
* F1 Racing Lightweight Chromoly flywheels incorporate special design features to enhance the airflow for improved clutch cooling
* F1 Racing Lightweight Chromoly flywheels work with every clutch including Exedy, ACT, Fidanza, Clutchmasters, and other OEM clutch kits
* CAD designed, CNC machined and computer balanced


Retail Price: $ 359
56005FX-HT #10


Our picture above shows the ACTUAL item
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Vehicle Application
1984 - 1989 Toyota Corolla GTS (4AGE engine)
1984 - 1989 Toyota Corolla (4AGE engine)
1984 - 1991 Toyota Corolla Sedan & Wagon (2WD, 8 bolt crank only)

[Rice86]

after all this, light flywheels wheels are better for any performance application...

like i said, light flywheels is a must get =D

[greeneyes]

Those with milled teeth don't have a separate ring gear.

Traditionally the steel ring gear is shrunk onto the flywheel, and when the teeth are chewed away in the spot where the motor always stops you could drill the old ring gear off and replace it with a new one.

I'm not sure what happens when your expensive flywheel has lost its teeth- do they expect you to lathe off the teeth and sweat a ring gear on, or do they expect you to throw the flywheel away and buy another.

[Frak]

You generally find that a 4cyl engine will always stop in one of two places, so if your ring gear starts to chew out, remove it from crank, turn it 90deg and get more life.

It's generally the lead in face of the teeth that gets a hammering so turning the flywheel gives new unmolested teeth for the starter pinion to mesh with., probably good idea to change starter pinion as well :)

[lo_rolla]

If that V10 has a 100mm bore, the stroke is less then 10mm.