If you are speaking of the later (swing-spring) models, that might be pretty much accurate. However, earlier fixed spring models don't suffer from the effects of that pitiful rear suspension (excessive body roll), so the normal cause and effect issues are in effect.
As a rule: 1. Increasing front stiffness increases tendencies toward understeer. 2. Decreasing front stiffness increases tendencies toward oversteer. Obviously, you can't state the above without adding: 1. Increasing rear stiffness increases tendencies toward oversteer 2. Decreasing rear stiffness increases tendencies toward understeer. Of course, these all have to be taken with both ends into consideration. The later Spits can take a lot more front swaybar without displaying adverse understeer problems because the rear is so loose to begin with. As an example of what I am talking about, when I first started monkeying with the original suspension on tiny Tim, I installed a large additional main leaf to the already heavy GT6+ rear spring stack and knew that I had to stiffen the front. I had some custom 350 pound coils made for me and installed a 1 inch front bar. The first autocross I entered in showed me that the front end was much too stiff because it was all I could do to keep the car from plowing in turns. I went to the 7/8" bar until I installed the dual A-Frame suspension and Koni Coil-over shocks to the rear and was able to put the 1 inch bar back on. After I converted the car to street use, I went back to the 7/8" bar for comfort reasons. Joe -----Original Message----- Increasing front roll stiffness primarily creates two different events. The end result is the combined effect of these two events. The first is to reduce body roll. This is a good thing. When the body rolls over, this rolls the wheels over, which is never good for handling as the sidewalls of a tire aren't noted for doing good things on the pavement. So reducing body roll is good as it keeps the tires more upright, and this promotes better handling, typically reducing understeer. The second thing is to increase the load on the front tires. This is not a good thing. This increased of loading more rapidly overloads the tires, causing them to slide, or understeer. This is not a good thing. In the case of the Spitfire, particularly with the swing spring, the net effect of a stiffer front rollbar is better handling. The car stays flatter, maximizing the first point above. As there is virtually no roll resistance in the rear, you are not particularly increasing it in the front, the front is already taking it. So you net out with better handling. That's why this setup is virtually universal on all racing Spitfires, it works. _______________________________________________ Support Team.Net http://www.team.net/donate.html [email protected] http://autox.team.net/mailman/listinfo/spitfires http://www.team.net/archive
