Barney, Actually stackong two front bars was quite simple and inexpensive. I
used an aluminum pillow block, two levels, i.e. a 3 layer sandwich at the frame
mounts, and an aluminum bar stock strap at the A arm connections. Very simple
but it worked. The car is still around as a vintage racer out of the Dallas
area. Still quick w/o a whole lot of power. John
Barney Gaylord wrote:
> At 03:52 PM 8/10/98 -0500, John Roper wrote:
> >I ran a B is DSP with substantial success for several years. .... I
> stacked two front bars, used heavy front springs, built in much negative
> camber, lowered the car 2" all around, and took the two small leaves out of
> the rear springs. .... Could pitch and catch, and steer on the throttle.
> .... I did try a rear bar and found it made the car very twitchy.
>
> Yep. If the the car is reasonable in handling to begin with, increasing
> the rear roll stiffness will induce oversteer, leading to twitchy on
> switchbacks and sudden steering manuvers.
>
> Unfortunately, nearly all MGs (as stock) are too stiff in the rear to begin
> with. The fact that they aren't terribly twitchy in stock form has to do
> with the limited lateral traction of the stock tires, and the fact that
> large amounts of body roll in the turns induces a nasty camber error on the
> outside front wheel that can lift part of the tire tread off the ground.
>
> Increasing front roll stiffness will continue to reduce push (understeer)
> until you can keep the inside rear tire on the ground in hard turns. Once
> all four tires are firmly planted on the pavement, additional increase in
> front roll stiffness will once again begin to induce more push.
>
> And I intend to remain in Stock class, so everything you did for Street
> Prepared class, I can't do, except for the front sway bar(s) and stiffening
> the existing shocks.
>
> I think I would put down good money to try a 7/8" front sway bar in place
> of my current 3/4" bar, but so far I haven't found one to fit the MGA.
> Here a little bit goes a long way, because the tortional stiffness of the
> bar increases as the fourth power of the diameter. The 7/8" bar would be
> 85% stiffer than the 3/4" bar, and nearly 4 times as stiff as the factory
> optional 5/8" bar. Of course these figures would be tempered somewhat by
> the bending action of the angled ends of the bar where stiffness only
> increases as the square of the diameter.
>
> Your idea of stacking two bars sounds interresting, but it may be easier
> (and maybe cheaper) to have a single larger bar custom fabricated.
>
> Barney Gaylord
> 1958 MGA with an attitude
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