Postby Hasbeen » 26 Jan 2017 03:34
Unless you are an extreme member of the slow in. fast out, don't install an uprated, or heavier front roll bar, unless you plan to match it with a similarly uprated rear bar. Well that is unless you have made some modifications that have induced considerable oversteer in the car.
The action of a front antiroll bar is to transfer weight when cornering from the outside front wheel to the inside back wheel, thus reducing grip at the front, & increasing it at the rear of the car. Thus increasing the front roll bar stiffness leads to understeer. Rear rollbars give the opposite effect.
Exactly the same effect can be achieved with spring rates, & to a lesser effect with shocks. The real advantage of roll bars is that they do it without much effect on the spring rates. Thus you can move the grip around without making the things suspension so stiff it bounces all over the place, except when driven on a billiard table smooth road.
I have 30% stiffer bars on each end of the 7 & the 8, [24mm I think]. This is near perfect on the 7, but if doing it again on the 8, I would have a decision problem. With all it's power, at less than about 7 tenths, applying power merely pushes the front off the road. Applying enough power to stop this by inducing a power slide attracts so much unwanted attention, [law], I just don't do it. At race track speeds it all works quite well.
If I lower the rear grip with roll bar changes I then have that wheel spin problem with any enthusiastic traffic light take off, unless I slip the clutch excessively.
What a long winded way of saying, working at one end of the car will probably induce deficiencies at one end, may be a not expected change at the other end. All modifications should be balanced to work together.
Hasbeen