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I have AO48's and LSS wheels on my base suspension car.

Because of this, inside the door is 26F 28R cold recommended for front and rear. I'm sure this is too much pressure for the AO48's.

What is recommended by Lotus for AO48's cold?

I have only seen recommended hot track pressures by searching. I am looking for cold pressure suggestions for street use.

Thanks! :up:
 

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26F and 29R IS the recommended cold pressures...hence why its printed on the car.

Edit: Ah, you added the LSS wheels and A048 tires to a base car... pressures are 26F and 29R.
 

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For a recent trip I took, I upped the pressure to 28F 31R and got considerably better millage, without losing any noticeable street performance. Tires max psi is about 50. If you stick to the recommended 26F 29R you should be fine.
 

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i'm running 25 front and 27 back. Just trying these after reading some older posts after my rears wore out. The wear pattern on both rear tires was much more in the center than the outsides of the tires, so the 29 stock pressure was too high. my guess.
 

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Can you help me understand

I think the requirement for tire pressure decals on all new cars is a little absurd. Most mechanics swear by those tire pressure decals now and they are touted like they are the gospel or something.

Here is my problem with the tire pressure decals...

I have seen some new cars that have different types of tires mounted - these are brand new cars mind you - and the tire pressure printed on those differing tires varies. For example, I saw a cobalt with Firestones, Goodyear and Dunlap (i think) and some said 35 max all the way to 45 max? That is just on new cars. My understanding is that some auto manufactures have contracts with different tire companies and some cars just get what is available at the time. So right there, I see a potential conflict.

Now lets say you replace the tires with something different...maybe you get a different compound, different manufacturer...who knows, but you change the tires. Maybe you go to a different size rim all together. It is very likely in this example that you will have altered the tire pressure requirement as designated by the tire manufacturer.

I have a hard time believing that whatever reccommended tire pressure is put on the decal always applies if you get different tires. Different manufacturing techniques and different tire types (like run flats vs all season vs mud and snow vs dry pavement) may likely require different pressures.

I feel bad for those who swear to go by that sticker instead of what the manufacturer put on their own tires. I guess the manufacturer of the tires doesn't know what they are talking about?

Help me understand this...where am I wrong or mistaken. :shrug: I get that the tire pressure on the decal is supposed to correlate with the weight of the vehicle but again tire manufacturers have different techniques, compounds and constructions. I would think people should be advised to go by what is printed on the tire.
 

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I agree...but disagree.

The pressure on the sticker is supposedly the "optimal" pressure with stock tires. In the case where the car manufacturer throws on any tire they get hold of...then the sticker is bollocks.

Speaking specifically about the Elise...it is known in the community what the proper pressure is for the make and model of tire.

The tire manufacture does not list the optimal pressure on the tire (only max load capacity pressure) because they can not. Optimal pressure can only be known when the application is known. Max load pressure will make the tires feel like you are driving on steel if you don't have enough weight on them.

To take it further...I have to go weigh my motorcoach in loaded condition, calculate corner weights, consult the tire manufacturer's chart regarding the highest corner weight for that axle and apply that pressure for all tires on that axle. I also have to take into account dual or single axle and dual or single tire per axle! :crazyeyes
 

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I'm running 26F/27.5R cold on A048s.

I was running 29R but the first set of tires showed a lot more wear in the center than towards the edges.
 

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29 is to high for the rear as others have said, you will wear out the center of the tire before the edges. Ive been running 26F 28R and get much better wear.
 

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26/27.5-28 is good for me with either the AD07's or A048's on street, but I take it one step further. In CT a daily temp range this type of year is 70-90 degrees. If I set the car for 70 degrees (on way to work in morning) car is a brick from lunch on (when I usually play a little more) So I set all my vehicles based on a daily median temp. That way my pressures are always 1lb +/- from my but-o - meters ideal. Has worked really well and I'm getting perfect tire wear even with all my camber modifications for track use. Try it, you'll like it!!!:coolnana:
 

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The pressure printed on the tire is the maximum pressure, or not to exceed when cold. Some tires are rated for extra load, or a reinforced side wall and will have a higher max pressure. If you want to carry extra weight in a SUV or truck, like a concrete statue you wife had to have on vacation and the normal pressure is 32 the tire might have a max pressure of 45, you could pump the tires to 45 and take them back down after the trip.
The vehicle manufacturer calculates how much weight is put on each tire under loaded conditions not sitting still. They determine how many square inches of tire is on the ground and get PSI or pounds per square inch. They will adjust that if the car tends to oversteer or understeer, but lean towards understeer. That tire pressure is the same for summer, all season, snow or mud tires. For street driving this will change very little with a larger size, competition driving is completly different.
Joe
TheTireShoppe
 

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The pressure printed on the tire is the maximum pressure, or not to exceed when cold. Some tires are rated for extra load, or a reinforced side wall and will have a higher max pressure. ...
The vehicle manufacturer calculates how much weight is put on each tire under loaded conditions not sitting still. They determine how many square inches of tire is on the ground and get PSI or pounds per square inch.
Joe
TheTireShoppe

Thank you Joe for the explanation - I understand that but what I am questioning is the premise this is based on. If the vehicle manufacturer is basing the printed reccommended pressure on the PSI of the stock tires - wouldn't this be meaningless if I changed to a different tire by a different manufacturer. Some have stronger sidewalls, different compounds and compositions from others. I don't understand how the car manufacturer can make a blanket statement that really only applies to the specific stock tires the car has. And again, there are some instances when some cars have different tires by different companies on the same rims depending on what is in stock (like Chevy Cobalts for example - you will find some at dealerships that have the same rims but different tires). I would think the tire manufacturer should be the athority on what is reccommended based on the max and type of tire. :shrug:
 

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The vehicle is supported by air pressure not by the tire. A runflat tire will support the vehicle when the air is removed but when inflated it rides on air. When you change tire brands the size of the air chamber stays the same. A tire with a reinforced sidewall is stronger to take more cornering forces and can hold more air presure to carry more weight. The presure printed on the tire is the maximum not the recommended.
The vehicle manufacturer plac has the information for the OE size and often optional sizes. The information is for normal highway driving. I've seen charts for size, presure, weight and they're pages long. They wouldn't fit in a door jam and most people would never read them.
Joe
 

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My AO48 rears have worn in the center at 29psi cold, I've dropped to 27psi but the damage is done. The fronts are looking good at 26psi.
 

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I ran 23/26 cold in AO48's on the street and then around 25-27 hot on track. As others said, running the higher pressures on the street ends up burning out the center of the tires over time.
 

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In order to get balanced wear, pressure may also need adjusted based on the relationship of rim width to tire width. For example, if you run the exact same brand and make of tire on the same rim but try out two different sizes... 225/45 vs. 245/40, you'll usually need a little less pressure in the 245's vs. the 225's to keep them wearing evenly.

Max pressure listed on the tire itself, as others have said is just that... it's only really intended to be run at that max pressure if you also have the max load on the tire. It's more obvious on LT tires where load range C tires usually max pressure at 40-50psi, load range D (for heavier loads) is usually 60psi, and load range E (even heavier rated) is usually 80psi.

When i switched rims and tires (from C rated to D rated) on my g500 i found i needed to go from roughly 30psi to 40psi to keep them wearing evenly.

One thing is for sure, the settings in the door are just guidelines at best, and the 29psi cold definitely seems to be too much air for even tread wear on the tires i've had back there. I'm starting with 24/27psi cold in my new Toyo T1-R's to see how that goes.
 

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In order to get balanced wear, pressure may also need adjusted based on the relationship of rim width to tire width. For example, if you run the exact same brand and make of tire on the same rim but try out two different sizes... 225/45 vs. 245/40, you'll usually need a little less pressure in the 245's vs. the 225's to keep them wearing evenly.

Max pressure listed on the tire itself, as others have said is just that... it's only really intended to be run at that max pressure if you also have the max load on the tire. It's more obvious on LT tires where load range C tires usually max pressure at 40-50psi, load range D (for heavier loads) is usually 60psi, and load range E (even heavier rated) is usually 80psi.

When i switched rims and tires (from C rated to D rated) on my g500 i found i needed to go from roughly 30psi to 40psi to keep them wearing evenly.

One thing is for sure, the settings in the door are just guidelines at best, and the 29psi cold definitely seems to be too much air for even tread wear on the tires i've had back there. I'm starting with 24/27psi cold in my new Toyo T1-R's to see how that goes.
I think you are in the ballpark on typical street pressures. I'm getting pretty good wear in that range.

:up:
 

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my tire pressure

I run 28 front, and 29+ rear.

I get better milage at 29+ in the rear with Goodyears - currently on 3rd set of rears. Only got 12K miles on the OEM rear tires at 28 lbs (also seemed to wear more in the middle), around 15K on the Goodyears with even wear at higher pressure.

Today I replaced the original fronts after 35K miles (even wear) - saw no reason to use a different brand.
 
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