Heh, heh, we have gone on about this subject before so let me set the arguement in this version. We have a 1993TS Series Speciale with 355 wheels and Pirelli tires - Assymetricos and Directzionales in the stock sizes. 348 17" stock wheels and tires state 2 sets of pressures for this car depending on the tires mounted. Problem is that you can't get either one of the sets any longer so you have to either use the same manufacturers and get close to the correct sizes with different models or switch to something else that works, like some Korean tire (over my dead body will I put these on my Italian exotic ) For the record the inflations are 36 front and 38 rear. Seems kind of high to me, but I'm not the designer. For the 355, on the other hand, we have a completely different approach to tire preasures. Recommended for Pirellis are 32 front and 29 rear on the stock 18" wheels. Hmm, pretty disparate, eh? So what gives? Theory 1: The 355 has a computer controlled (mostly) suspension system that adjusts the settings to optimalize handling and ride so the factory uses conservative tire inflations. As opposed to the 348 which has no computer and a single suspension setting, so you compromise. Theory 2: The 355 was changed to dial out understeer, hence the lower rear settings. The 348, well, the factory didn't know better so they just moved the wheels outboard in the SS's and Spiders, but they were looking for an understeer condition condition for safety, which is odd since the wheel stagger already dials in a bunch of understeer. Then there's that notorious high speed front end stability issue with the earlier cars to deal with. Theory 3: The 355 18" tires have much stiffer sidewalls so they don't need as much pressure to perform as the 17" 348's. Hmm, sounds good. So here we are. As it turns out, I am running about 35 lbs all around as a compromise. I know that if I lower inflation pressure in the front, the car plows which is not good, so I need to keep it up a bit. Rears are difficult to break free at higher pressures, but at lower ones, they feel mushy in the corners. However, bursting a rear tire from high inflation and temperatures from hard cornering is not a good thing. So at the risk of starting a debate, what are the thoughts on this? I am actually thinking of doing 36 front and 34 rear (as if I could tell the difference ).
1. Buy a pyrometer. 2. Do a hot lap. 3. Measure temps across the tire. Hot outsides=air up Hot insides=air down Barack Obama=air way up (use hot air)
PLugz you are no help. This is a suggestion for tracking the car or driving it continuously around the same circuit. The objective is to achieve a balanced inflation program for driving the car around. B-a-a-a-p, try again. And that crack about Obama belongs in the Political section even if it is mostly correct.
In short, yes and depending on the track. As an extreme example, take a NASCAR track (oh hell, take the whole series - away ) where you turn left at high speed. Obviously the right tires are going to get hotter so you adjust tire pressures accordingly. Same with any track set up. You adjust pressures to fit the characteristics of the track - harder right turns, or something. Now if you were doing a flat moderate speed road course with an equal amount of left and right turns of the same dynamics, then maybe, yes, you would be correct. Man, I am beginning to sound like goth. Think I need to watch some MoeLarryCurly.
Yep what a piece of crap it is too. Just a 550 HP twin turbo full Novitech that costs $85000 on top of a regular 360. A car I might swap out the 348 for if I ever hit the Lotto. Never going to happen.
