In a message dated 5/5/2006 10:11:16 AM Central Standard Time,
tr3driver@comcast.net writes:
> Most people don't like rear bars on TRs. Adding roll stiffness in the rear
> aggravates the "wheel lift" problem caused by the front roll center being so
> much lower than the rear. Personally, I think a soft bar in the rear helps
> the
> solid axle cars, but I don't think it would help with IRS.
>
I think the major problem with rear sway bars in the IRS cars is due to the
camber changes with suspension travel. Under heavy throttle the rear squats
and the camber goes way negative and the outside rear tire will dig in and the
front end will plow. That is not a problem unless you want kick the rear end
out to help around a tight curve. But under no throttle, or even more so under
braking, the suspension extends and the rear camber goes positive and the
rear end tends to break away.
Notice I said especially under braking. When entering a curve that is
unexpectedly tight the natural tendency is to brake and this is when the car is
most
likely to loose the back end. To combat this Triumph added a front sway bar
and no rear to dial up the understeer so that the above condition induced
oversteer is still slightly understeer and the car stays on the road (or at
least
doesn't go off backwards).
Stiffer shocks will slow down the transition from understeer to oversteer.
When I was running Koni's with my original springs I found I could steer the
back end with the gas but it was in the reverse of what one would expect. But
when that conversion fouled my tire I switched back to a set of "Heavy Duty"
rebuild levers. But they were so soft that the car would transition between
oversteer and understeer so quickly I couldn't keep up. One time I found
myself
in a situation that if there was any other traffic I would have been in
trouble. And I wasn't going that fast (only 25 or 30).
Stiffer springs reduced the amount of camber change and stiffer shocks slowed
the transition. That coupled with a premature end stop because the shocks
are a bit too short (see my previous Email) and the oversteer is minimized and
much less hazardous.
But maybe I'll give the no rear bar a try. Just because inquiring minds want
to know.
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