Again, sort of...
>Umm.......... yes and no. The reason the spring rates on the front are so
>high, is that the
>spring itself is inboard from the kingpin. Look at a McPherson strut. The
>spring is
>in line with the swivel axle (well almost), if the MGB has this type of
>suspension,
>the spring would be about 120lbs->150lbs. But the spring on an MGB is
>inboard and
>acts like a lever so the spring rate has to be higher. To get an accurate
>measure
>of the spring, it has to be performed at the wheel - i.e. if you sit on the
>fender and
>your weight is 150lbs and the car goes down by 1 inch, then the true spring
>rate is
>150lbs/inch.
This would actually be your effective spring rate, the true spring rate is
calculated or measured based on the actual spring. The effective rate on
the front of the car is something close to half the real rate, or about
240#/in for a stock spring.
>On the rear, the axle is acting directly in the spring, there is no lever
>Action, so the spring rate is different.
The axle is acting directly on the spring, but since it is mounted in the
center of the spring, it must bend the spring in two placed to compress it,
so there is a multiplication factor here of 2:1. You don't see rear spring
rates quoted often, but the stock springs are about 110#/in. Add in the
fact that you are bending it twice (in front of and behind the axle) and you
get an effective rate of about 220#/in
James Nazarian
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