Last edited by StruanR; 22-04-2014 at 07:58.
Yes and no. Say you put tire "A" on your car. This tire has specific properties which allow it to handle and produce a certain amount of lateral force/G-force with a given amount of normal load on that tire. (normal load=vertical force pushing down) going around a 30m radius turn. Your front/rear weight dist. is 50/50. Tire "A" gives you oversteer. Switch to tire "B" now, all things being equal, same chassis set-up, wheels, etc... Now you are getting less oversteer on that same 30m turn. Put simply your tires are the most effective part on any car, without them you wouldn't go anywhere. They create all of the forces which allow you to maneuver a car the way you want.
If you know how much normal load the tires can handle, you can determine your lateral forces, telling you where to maximize your weight distribution. A simple goal when designing a car from scratch, that I tried to do was aim for neutral steer, and design the suspension such that you can tune to over or under-steer. There's another factor and this one is "the joker". This is the driver, the biggest variable of all.... Some people like oversteer, some like understeer and also in varying levels.
So there's no golden egg you can hit. When I said aim for "neutral steer", this is what I tried to do in my FSAE/college days. Some tires may not allow you to tune for understeer, no matter how much adjust ability you have in your suspension and like-wise for oversteer. Hopefully this answers your question somewhat.... I've read LOTS of vehicle dynamics books... From Aerodynamics, all the way down to chassis/suspension design. If you want to learn more pick up a Carroll Smith book called "tune to win" and if you want to get into the crazy stuff, there is always "Race Car Vehicle Dynamics" by Milliken and Milliken.
Last edited by monoposto; 27-04-2014 at 03:21.
Thanks monoposto. There's a saying, start with the end in mind. Whilst it may take a considerable time to achieve my "dream", I want to try and tease-out at the beginning the key factors which will make it more likely to be realised. Tyres are obviously a huge factor and set up will have to be geared around the tyres, so I'll worry about that later. What I think I've learned to date is that I need sufficient power (a 2.5 may we'll be sufficient, but a 3.0 or 3.2 even in standard tune will do the job), a LSD (Q2, Quaife, Gripper), 5 speed box with roller bearings on input shafts and the strongest driveshafts I can afford!
I did wonder whether a 2.5 was preferable to a 3.0 or 3.2 (or vice versa) from a weight distribution point of view, but as no one has mentioned it I'm guessing the difference is negligible and can be dialled out in the set up.
I've got a mate who I'll be calling on to help me with the set up, he's done vehicle dynamics in F1 and has all the books!![]()
Remember something has to be the weakest link that breaks first. If it's not the driveshafts (easy to replace) is it to be the gearbox (expensive & more difficult)...strongest driveshafts I can afford!
Honestly, I think people get caught up too much in what "set-up" they run. When stock is probably the best and least likely to get you in trouble (im using "you in general terms here, not specifically you!). Spend your time karting and getting used to feel the tires and how things react with different inputs. You'll have much more success going that route than the "race car set-up" route.
Last edited by monoposto; 02-05-2014 at 04:00.
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