Ferrari recommends 30 front / 29 rear psi. I have Pirelli P Zeros. I find the ride to be really stiff and bouncy at the above setting. I use 29 front / 28 rear and like it a lot better. It feels more natural, less tense/nervous. What tire pressure do you guys run?
Im sorry, but find hard to believe you feel any difference with just one PSI lower. My advice is to respect always Ferrari instructions. They know what they do.
Unless tires are nitrogen filled, you're going to have a +/- a few PSI based on temp, driving aggression, etc. If you're getting noticeable ride changes due to that minimal of a PSI change, you likely have some other suspension issue that coincidentally occurred with the tire pressure change. Best, Ron
I can EASILY feel a 1 PSI difference in tire pressure, have done that many times on track. I don't think 1 PSI off manufacturers recommendations will cause any issue; besides, you may find your gauge is not accurate. A good gauge accurate to .1 PSI will run you several hundred dollars.
1 PSI = 0.069 Bar. Reading capacity of any street gauge is 0.1 Bar. Accuracy is +/- 0.3 Bar. I'm sorry. Still hard to believe.
Check here: Longacre Racing - Online Catalog: Electronic Wheel Scales, Gauges, Pyrometers, Chassis Setup and More! Not cheap, but I go through between 5-8 sets of tires a season on my race car, so it makes sense. It also does temperature compensation, which is invaluable in setting starting pressures. Typically, on the race car (Lotus on Yokohama slicks), I am shooting for 28 psi hot. I can feel when the tires go to 29, and at 30 the car is undrivable. Granted street tires are somewhat less sensitive, but noticing a 1 psi change is very possible. Since I have the gauge, that's what I use to set the Ferraris pressure as well. I would agree that the typical street gauge would be less accurate. Cheers, Ron.
I second this. When I used to race I could tell -- with race tires -- when I was off by 1-2 psi. For street driving, I can't imagine how it would be noticeable.
A lot I would to tell you about accuracy versus increment reading on gauges. But I was not talking about racing ambience. If you say that you can feel 1 PSI difference in race ambience, obviously I will not doubt it. I do not have that knowledge. I was referring to a 458 street car and I can assure that I cant feel 1 PSI difference. Can you?
Ahhh but what air temperature do you set your tires at? Remember the factory pressures are for COLD (65F). I love the Longacre gauges. Thats all Ill use. I adjust the pressures several times a year due to changes in ambient temperature.
On the Ferrari, I set the pressures when the tires are whatever ambient is, so, like you, I adjust seasonally. For the Michelin tires, the manual recommends 30.46 F, 29.0 R. I round up to 30.5F On the race car, I use the temperature compensation feature which references 80f for starting pressures, then adjust hot pressures to 28 (actual, non compensated) in the pits. What I should be doing is using the surface temperature of the tires, but to do that right, I would need another person right on pit wall. Trying to show my wife how to do this. Best, Ron
I agree there must be some pressure you can tell a tire is low or high, 1,2, or3 psi probably not. Not sure. My older classic cars show " off " tire pressure more than the newer cars. Some of my cars give a dashboard warning at 2 psi. all I know is I have aircompressors at my car storage area and at my garage. I just fill the tires to the proper pressure and never look back. I try to get them spot on but within 1=2 psi. I some times do not recycle to a car for 2 months. Not matter I always check the air pressure. I think it is therapy Life is too short to worry. Of course I do not race and I know nothing about those requirements. Best Lee
Also a good habit to check pressure the next day after use. You will catch leaks that are too slow to pick up during the trip but fast enough to go down in a couple of days. Lots of nail pick ups fall into this catagory.
Without wanting to sound stubborn and repetitive, I should remind you that 458 front left tire, just after a few miles pushing, assumes more than 3 PSI comparing with the front right tire. Naturally due the higher temp increase on the front left tire on all the 458 models. But the point is: Does anyone can feel on the steering this pressure difference? I guess not.
+1, and I have running cars on racetrack for ages... Despite of the fact that cold pressures are not kept once the car is rolling, depending on weather, the road shape, and how it is being driven, the pressure would raise 1 psi to 14 psi per tire.
Unless you're driving in circles, that 3 psi increase in one tire and not the other is probably your tire gauge out of calibration (and the onboard TPMS is far from accurate).
Dont know if you have a 458. I guess not. Otherwise you would understand what I said. Its not a gauge malfunction!
In a hot climate in Asia My tyre guy told me not to follow the 210 front 200 rear Kpa unless u are on race track Normal road driving he told me to put front 250 kpa n rear 280 Kpa He say that this would help for street road driving ....Have anyone try filling to this pressure Ferrari 458 is an rear engine So the rear is heavier n tyres are bigger .Why should the pressure be lower then the front? Another question if u pump up to 280 and decided to move back to 220 kpa Will it spoil yr tyres?
