freewheeling was not just an economy device. it was due to the nature of
the pre-mixed (oil and gas mixed in the tank of early models versus the
better remembered oil injected later versions) 2 stroke engines. when
decelerating down long hills or slowing down from being at speed a pre-mixer
looses vital lubrication when the thrittle is returned to rest position
while the car is still in motion (reguardless of road speed). so if you
were trying to "engine brake" down a hill the throttle would be at an idle
position but theengine would be near it's top end of rpm range. in this
xcondition the engine would be starving for lubrication(oil mixed in it's
gas) and over heat the rod bearings and begin to melt the cages that
space/retain the rods double row of rollers on the crank. this would result
in a siezed engine, just from deceleration! freewheeling was a importaint
factor in keeping rpm's down in deceleration situations. it was later that
it was discovered to be a "economy" device by which drivers could coast at
speed to conserve fuel consumption. and quirky as it was it was continued
in production up into the saab model 99.
chuck.
ask a guy who owns 2 cars powered with saab 2 strokes!
1960 saab 93f
1967 scca h-modified sports racer
1959 h-production bugeye
----- Original Message -----
From Chris Kotting <ckotting at core.com>
Cc: <spridgets@autox.team.net>
Sent: Thursday, November 16, 2000 12:56 PM
Subject: Re: rubbish was Re: torque
> My understanding was that the freewheeling on SAABs was because of the 2
> cycle engines. There were some problems with them on "overrun". I
> don't know any more details than that, though. (Yet. I'm still hoping
> that my MG loving bride will see her way clear to allowing a Sonnett in
> the garage.)
>
> Christian Stanton wrote:
> >
> > Leave it to Saab...they have had a few innovations (and flops):
> > - Front wheel drive (how strange! since 1948)
> > - 2 cycle cars (umm..you want me to add oil to the gas)
> > - Freewheeling (for economy???)
> > - Turbocharging (1st passenger turbo in 1978)
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