Do flywheels increase power

[thexav]

I know that a lot of you guys have lighter flywheels. I also presume that it makes the engine change revs more quickly.

Does a lighter flywheel actually add power?

I think it might make the engine more powerful because it has less weight to rotate but does this make much difference?

 

[stamford]

It does not add more power, a lightened flywheel reduces the kinetic energy therefore allowing the engine to hit its peak powerband much sooner. The only downside is it can tail off quickly if not kept within the rev range or if going uphill etc.

 

[thexav]

So on a dyno would the power output read the same then?

 

[stamford]

Yes, it would just hit it sooner.

 

[HDi fun]

Basically yes, power would be the same. It will just rev up a bit more enthusiastically in first gear or neutral. For road use it's probably not necessary. Especially when you consider the twin balancer shafts in so many engines - they have far more rotational inertia than a fly.

 

[old-git]

Yes, it would just hit it sooner.

For drag racing a heavier flywheel in often used. By storing rotational enegry in a heavy flywheel the engine is less likely to bog down on the line.

However, for my car, I am not yet convinced this is the way to go. I somehow don't think that with 600+bhp in a 650kg car I am going to have too much trouble with bogging down on the line and the lighter flywheel will be an advantage in the sprint section of TOTB.

 

[HDi fun]

Yeah, without doubt in a lightweight flywheel would help massively in such a low mass extreme performance car. The mass of the car itself is not enough to require much rotational inertia to help off the line performance.

 

[thexav]

Thanks once again for the great response guys. I can now sound like I know what im talking about.

 

[old-git]

Thanks once again for the great response guys. I can now sound like I know what im talking about.

Some of us SOUND like we know what we are talking about

 

[obi_waynne]

I thought it was time to bump this thread, we've not really had a detailed reply to it yet and I know there is quite a bit of knowledge out there about flywheels.

 

[HDi fun]

Yes indeed. But discussing flywheels in isolation is like discussing one particular base ingredient in a masala spice blend.

 

[stamford]

Puma Race Engines always had some excellent info to read, here's a thread about it on another forum. Page 4 has the Puma bit.

 

[stamford]

I think the hyperlink in the thread option needs addressing, didn't realise it was a different shade to the normal text. I didn't copy and past the content due to the copyright footnote