Re: do i have to get a bigger rollbar if i get the 2Bennett setup?

[Luis Marques <marques@rtis.ray.com>]

PAT MARTIN wrote:
>  Keep in mind that if you lower the car the suspension geometry has
> changed not neccesarrilly for the better.  And if you are starting at
> a lower point that could mean expodentially increasing geometry
> problems.  Not to mention what do you set the alignment at?  Stock
> setting may not be right.  While weight transfer is an issue you could
> accomplish this by simply stiffening at the stock height.  This is why
> the 84 4kq springs might be the best bet.

Pat has a very good point.  Usually the factory designs suspensions so that they
work well over a limited design range.  If you venture outside this range, weird
and bad things begin to happen.  The no. 1 bad thing that will happen to a 4kq
that has been lowered too much is bump steer.  The tie rod moves up and down
following a different arc than the strut, so if the suspension is disturbed, the
toe can change without turning the steering wheel.  This can also happen at the
rear, since the rear suspension is a copy of the front one.  If you use your car
in very flat and good roads, this may not be a big problem.

The other bad thing that could happen is that you run out of suspension travel. 
The uni-body chassis will take a beating and you will feel bumps up your spine. 
Finally, It is very possible for a strut/a-arm suspension to start changing
camber towards positive if compressed too much.  Usually you want the car to
have maximum negative camber at the point of maximum suspension compression
during cornering.  If the static ride height is too low, you will miss this
point and will need excessive negative camber to compensate.

Stiff springs will help a lot in controlling body roll and maintaining an
optimum contact patch, but weight transfer is still a function of how high the
center of gravity is and how fast you are turning (and how wide is the car). 
The only way to improve the situation here is to lower the center of gravity. 
That said, a car at stock ride height with a properly tuned suspension that
maintains an optimum contact patch will run circles around a lowered car with a
screwed-up suspension that doesn't.

- Luis Marques