flywheel sizes

Does anyone have information on SAE flywheel sizes ?
Do the car manufactures recognize these standards ?
If the manufactures do recognize them why can't different manufactures
flywheels be interchanged?
Any information at all will be helpful.
Thanks.

On 1 Dec 2005 18:30:11 -0800, wrote:

>Does anyone have information on SAE flywheel sizes ?

No absolute dimensions at hand, at the moment. The SAE
Handbook does detail configuration of both flywheels and housings.
Flywheels are designated by the nominal size of the PTO clutch they
are made to drive, from 6-1/2 inch to 14 inch. Housings are
designated simply with a number, with 6 being the smallest. Number 0
or 00 is the largest. (Don't remember exactly.....Number 3 is the
largest one I work with on a regular basis. It's used on many
industrial and truck engines rated up to about 350 BHP, continuous).

>Do the car manufactures recognize these standards ?

They may recognize them, but they don't USE them in normal
automobile production. Industrial engines (driving generators, pumps,
construction equipment, etc.) sometimes use SAE dimensions, sometimes
do not.
Adherence to SAE recommended practice usually renders
flywheels and housings larger and heavier than automotive designers
find practical. They're concerned with saving weight, space under the
hood, etc. Heavier flywheels also affect things like throttle
response and maximum safe operating RPM. And with automatic
transmissions, the torque converter usually IS the engine flywheel, as
well.

>If the manufactures do recognize them why can't different manufactures
>flywheels be interchanged?

As stated above, the auto manufacturers are aware of SAE
flywheel standards, but they don't use them on passenger vehicles.

>Any information at all will be helpful.
>Thanks.