healeys
[Top] [All Lists]

Re: [Healeys] Fly Wheels

To: Bill <bn1@pacbell.net>
Subject: Re: [Healeys] Fly Wheels
From: Dave Russell <rusd@sitestar.net>
Date: Thu, 30 Aug 2007 17:51:12 -0600
Hi Bill,

I don't know if this helps or not.

It's all about inertia. More mass requires more power/time to change speeds.

in a car with a 3.5 to 1 first gear & a 4 to 1 axle, in first gear, 
there is a 14 to 1 mechanical advantage for the engine to accelerate the 
car mass.  Thus the engine/flywheel only has to overcome 1/14th of the 
total car mass. In top gear the engine/ flywheel has to overcome 1/4 of 
the total mass.

Bottom line, for a given car weight, a light flywheel improves 
acceleration in proportion to the gear tht the car is in. Much more 
improvement  in first gear than in top gear. And of course much faster 
throttle response when the clutch is not engaged.

My personal experience with a BN2 is that a 13 lb flywheel vs the 
original 40 lb makes the engine/car more responsive in the lower gears & 
between gears. On this very long stroke engine, it has no noticeable 
effect on idle quality, engine starting, or ease of getting the car 
rolling from a stop.

Regards,
Dave Russell
BN2

Bill wrote:

>  Hi Greg,
>
>  While I'm sure there are many others out there much more versed in
>  physics than I am, the "#" sign means pounds, as in weight. It takes
>  more horsepower and time to spin up 42 pounds than it does 23
>  pounds. That means quicker acceleration and deceleration. I can
>  easily tell you the results, just not necessarily why. Would
>  somebody please help me out here?
>
>  Many thanks,
>
>  Bill Barnett '53 BN1 # 663
>
>  Go2ghill@aol.com wrote:
>
> > What at the numbers for the fly wheels mean, and why is one better
> > than another. Greg BN4
_______________________________________________

Healeys@autox.team.net
http://autox.team.net/mailman/listinfo/healeys

<Prev in Thread] Current Thread [Next in Thread>