Hey what.
So i was wondering, exactly how strict do you need to be to sticking to the 32-34 (2.2Bar) PSI target? I’m finding some cars heat the center of the tire if i even go above 1.8 Bar. I’m a little confused. Does it depend on tire compound?
If I’m going to be honest, tire pressure is still a mystery to me in Forza. Like I do see the 32 psi recommendation every now and then, and I don’t doubt that it’s a good target, but it’s just… I wish I had some solid numbers. Whether or not the pressure target varies by tire compound is a good question too
I was thinking a while back about making a post to crowdsource some solid data, since I do really want to know for sure what exactly goes into finding the right tire pressure. I guess some questions that I want settled are
- Does the optimal tire pressure vary with vehicle weight in Forza? (It does of course IRL, but in Forza I don’t know for sure)
- Does the optimal tire pressure differ between compounds/different thicknesses?
- How does tire temperature vary across different tire types?
There’s probably some good answers floating around already, but I want to back it up with some numbers as well. I know this doesn’t exactly answer your question, but I’d imagine it isn’t too strict
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2.2 bar is kind of on the high side of where i like to start from. Generally I start at around 1.9-2.1.
Run as little camber as possible to have even heat across the tire when cornering.
lighter cars can get away with less pressure while heavier cars need more. Stock tire saloons I run between 2.3-2.8 bar.
Tire width, compound and profile all play a part too.
And then its also track dependent. Flowing momentum tracks (Maple, Grand Oak, Hakone ect.) you can run higher pressures while more technical tracks need to be lower.
And then some cars you just throw all that out the window and see what works.
Are you working on the AMR Pro? Forget everything you know.
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Right now im trying to tune the ‘14 alfa 4c. I cant really get the tire pressure above 1.8 bar without the middle getting hotter then The sides.
For A class with sport tires. Its been good for me, got one win and a few podiums. I know its a light car so maybe that’s why i can’t get the pressure up before it feels too high
sounds about right for the 4C. some really light cars on race slicks I have down as low as 1.5-1.8.
Well that at least is reassuring. I thought i might be missing out on major performance gains with such low pressures. Thing is sitting at just under 1 Mg
Ultimately you want the heat to be pretty much the same in all 3 areas of the tire. ± 1 or 2 degrees isn’t horrible but you never want your outside edge to be the hottest. Conversely you don’t want to see the inner edge lose heat while cornering. This will be on the outter tires ( so on a right turn it will be your left tires. ). There is no magic number and trying to dial in tire pressures before your alignment is correct will be a pain.
Get your alignment right first then adjust pressure. Adjust camber until your tires read about the same temperatures in all 3 areas while under load ( cornering ). I find that Hakone is an excellent track to set alignments and tire pressures on since it has the long sweeping turns. Push hard into the turns to get the most heat in your tires. If you do this right, you’ll see where the middle of the tire is heat wise. If it’s cooler, add pressure. If it’s warmer, remove pressure. Ideally your inner and middle should read about the same with the outer being a bit cooler while cornering.
regardless of car, if your car is equipped with Race Tyres, your optimal pressure should be between 27.5-29.5 for both front and rear. That’s where the sweet spot is, and make sure you tune the suspension geometry accordingly
Best grip at 176f for street, 203f for sport, 221f for race
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There is no target and don’t listen to anyone who says that.
The correct tire pressure is different for every car. It depends on many factors, but the biggest factor is weight. Heavy cars need more tire pressure, light cars need less. Also weight distribution is also important. If your car is front heavy, the front tires will require more tire pressure than the rear tires to get a flat contact patch.
The only way to get tire pressure correct is to adjust and test until the heat is even across the tire tread.
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Precisely what I said.