Flywheel Lightening - How light is too light?

[onnaj]

I think the AE111 flywheel is already pretty light with 5.8 kg. The stock 4AGE flywheel is about 7.8 kg. I'm not a great fan of shaving flywheels, but let other tell what's a good weight.

[gotzoom?]

The F1 flywheel you can get on Ebay for around $180 is a Toda ripoff and made of chromemoly, so it's a quality piece. I'd go that route rather than risk a lightened factory flywheel exploding. If you decide to go the lightening route, you need to make sure it is balanced up to 8000rpm to be safe.

[yoshimitsuspeed]

This is another question that is completely relative to the owner and the purpose of the car.
My FW is 4.5 KG and I love it for all types of driving. I bet most people would stall the car several times before being able to get going though. That's also with a solid disk and mid level pressure plate. An agressive disk or PP would make it more challenging. If you were racing a formula car you could go insanely light. Even if you had a pure track dedicated AW11 or AE86 you could probably go under 3 KG. On the other hand some people might hate the feel and behavior of a 6 KG FW.

The other question you should be asking is can you safely remove material from the stock FW and if so how much. Be well aware of the havoc a FW can wreak if it comes apart at redline.

[yoshimitsuspeed]

Sorry I should have been more clear with my question. How much weight can I safely remove from the standard blacktop flywheel without running the risk of it tearing apart itself and everything in its way?

I would only have this done at a place that specialized in lightening flywheels and then I would leave it up to their discretion.
A lot of this comes down to design and pretty heavy engineering. If you removed the right material in all the right places you might be able to take a lot off safely. On the other hand just a little material in the wrong spot could be the end of things. If the shop doesn't know enough to tell you how much they can safely remove then don't let them touch it.

I also have an F1 FW in my car and have been very happy with it. I would go that route over lightening the stock FW.

[gotzoom?]

The crankshaft bolt pattern is the same for 16V and 20V. If you're running RWD, then you can use the same 200mm flywheel that the 16V engines use. Not sure on FWD, though.

[allencr]

Cast iron flywheels do not become unsafe from lightening as they are already unsafe just because they are cast iron!

[burdickjp]

Don't lighten an OEM blacktop flywheel. They're a great weight as they are. If you don't like it, sell it and grab a different flywheel, but as they are, they're pretty awesome.

[Jimmee1990]

Cast iron flywheels do not become unsafe from lightening as they are already unsafe just because they are cast iron!

This makes no sense whatsoever? Please tell me technically why cast iron is an unsafe material?

On topic, there really isn't much material you could remove from the AE111 flywheel as most areas you would remove it from on a 16v flywheel have been removed from the casting. If you need a lighter flywheel than that (5.8kg) you really should be looking into a chromoly or aluminium flywheel.

[onnaj]

You can use any 4AGE lightened flywheel. Be aware that it indeed has a 8 bolt pattern. If you go voor a 200 mm flywheel you need a different clutch. Stock size for late spec 16V and 20V's is 212 mm, so any 212 mm 4AGE flywheel will work on the same clutch.

[ga_goosh]

just get it skimmed and ballanced and throw it on it is all ready lighter then any other stock 4age flywheel

[Jimbobtx3]

No shop could tell you what is a safe amount to remove because ideally, no amount is safe to remove. The stress in a flywheel actually reduces as you lighten is at there is less rotating mass. Why they fly apart is that the reduction in mass does not allow for heat dissapation. You have effectively reduced the heatsink ability of the flywheel so the next 7000rpm start you do will likely heat the flywheel to the point that you start to get heat stress cracks. Next thing you know,, bang.

Buy the fidanza. You won't be dissapointed and it won't fly apart and kill you. A win win I reckon

[asjoseph]

.

[jondee86]

This thread needs more pics !!!!



This is an OEM flywheel from a smallport 4AGE, lightened to my specifications.
It is being used in my car and works just fine. I don't know how much weight was
taken out of it, but you will note that it was all taken from the outer rim. Nothing
was removed other than what you can see in the pic.

And this was done before the blacktop 4AGE was built... I reckon Toyota copied
my design Most problems with flywheels are caused by people taking material
from the wrong place (near the centre) or making the flywheel too thin in critical
areas. Lightening should only be done by an experienced machinist who has the
correct tools for the job. And then get the finished product balanced.

Cheers... jondee86

[apsogosGTi]

hello mates, below you can see some pictures from my blacktop 20v flywheel that installed to an ae92 2nd gen 4age 16v.I also bought and a 20v pressure plate and clutch disc to fit correctly.



also changed the oil seal down there with toyota genuine one.I Preffered the genuine one for its color looks like viton.I dont know if it is.



balanced. You can see the signs.


also used a 4AFE Clutch rear plate and a 4afe starter and relocated her to the intake side and all my starter problems dissapeared.My electrician add an extra relay for the starter too





I didnt remove weight from the 20v flywheel only a clearing material for the eye and the balancing.

Lastly i didnt want the flywheel to light much cause i want on a trip and high speeds , the engine rpms to be stable. The difference with 20v flywheel for my feelings was not big.The only thing i believe i sensed is when you have a gear inside and try to full throttle the engine ,the "wake" was faster than before.
I think there is not difference in accelaration generally. Now i am not 100% sure, maybe the difference is too small to sense it.
John

[Rogue-AE95]

Buyer beware, the Fidanza is a racing flywheel (e.g., meant to be removed; fasteners religiously re-torqued, every time the vehicle's driven). It is not intended for street application. Comprised of multiple alloys (e.g., all of which flex, at differential rates), the Fidanza is a European style hill-climb flywheel, meant to come off the vehicle, when the engine's broken down, after every event.

Fair warning: The Fidanza is a high maintenance unit. You'll need it off the car, at thousand mile intervals.

Can you back this up?

[jondee86]

Every now and then when the topic of flywheels and lightening and factory
versus aftermarket comes up, I like to post this link which has a bunch of
pretty valid comment... and pictures

http://www.roadraceengineering.com/clutchandflywheeltech.htm

There are a few other things that come into the decision making process
when considering a light flywheel. Apart from storing energy, the flywheel
also has a damping effect on engine power stroke pulsations. It is possible
to get unusual vibrations and rattling noises after fitting a light flywheel.
Not an issue on a race car, but annoying on a road car.

Depending on the vehicle and the lightness of the flywheel, there can be
an increased tendency to stalling, requiring a few more revs when taking
off, and better clutch control. Normally this is not a problem, but when a
very light flywheel is combined with a fully built engine and puck clutch,
stalling can be an issue.

Cheers... jondee86

[Billy_Andrea]

Buyer beware, the Fidanza is a racing flywheel (e.g., meant to be removed; fasteners religiously re-torqued, every time the vehicle's driven). It is not intended for street application. Comprised of multiple alloys (e.g., all of which flex, at differential rates), the Fidanza is a European style hill-climb flywheel, meant to come off the vehicle, when the engine's broken down, after every event.

Fair warning: The Fidanza is a high maintenance unit. You'll need it off the car, at thousand mile intervals.

That's such a ridiculous paragraph I don't even know where to start. It's not a formula 1 engine, it's a 4age with a slightly lighter than stock flywheel.
Even my Tilton 4lb billet 2 piece flywheel & unsprung twin disc clutch doesn't have a service / inspection interval like that.