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One question for anyone running the 245/45ZR-18 Continental ExtremeContact DW XL what are you running for tire pressure?

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Thanks again!:)
 

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For street driving...

Factory recommends 29 all the way around, so 29psi it is for any brand tire.




:jm2c:
 

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Nice looking car!

The experts tell us to run the TP recommended by the manufacturer of the car. The suspension is designed to function best for road conditions at a specific pressure.
 

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I ALWAYS run 35 in all 4. To me, many tires get "heavy" feeling under 30. And a lot of high performance tire manufacturers recommend higher pressures to give the sidewalls support. My Toyos on my Mustang were always run at 40. Like I said I always run my tires at 35, unless I'm autocrossing. At which point I run 45-48 all the way around depending on track and temperature.
 

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Factory recommends 29 all the way around, so 29psi it is for any brand tire.
The experts tell us to run the TP recommended by the manufacturer of the car. The suspension is designed to function best for road conditions at a specific pressure.
No and no. That figure is set for the OEM tires. Different tire make/models (and different tire constructions) require different pressures.

For my Conti DWS's I found that 29PSI was WAY under-pressure. The tires squeal on corners and feel soggy and heavy. So I tested the temperatures across the width of the tires with an IR thermometer after some spirited driving and found the temps in the middle of the tires several degrees lower than the edges, supporting the low pressure assumption. I did a few experiments and found that 33-35PSI was 'just right' for my tires.

Since then I found this formula you can try for your tires over on KappaPerformance (coutesy of Critterman): At what pressure do I run my replacement tires at - A formula. Plug in the parameters from YOUR tires and go from there!
 

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Plug in the parameters from YOUR tires and go from there!
This last sentence is the key.
Even with the same tires your pressure may not be the same as someone else with the same tires.
The reason is your suspension setup may not be the same as theirs.
 

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No and no. That figure is set for the OEM tires. Different tire make/models (and different tire constructions) require different pressures.

For my Conti DWS's I found that 29PSI was WAY under-pressure. The tires squeal on corners and feel soggy and heavy. So I tested the temperatures across the width of the tires with an IR thermometer after some spirited driving and found the temps in the middle of the tires several degrees lower than the edges, supporting the low pressure assumption. I did a few experiments and found that 33-35PSI was 'just right' for my tires.

Since then I found this formula you can try for your tires over on KappaPerformance (coutesy of Critterman): At what pressure do I run my replacement tires at - A formula. Plug in the parameters from YOUR tires and go from there!
Absolutely correct TS.

I cannot stress enough that the car's recommendation stops when stock tires are not reinstalled. Manufaturers do not know that the recommended pressure will work with all tires of the same size due to huge difference in compounds. I think the DWs would be moderately underinflated at 29.

I put larger tires on most of my vehicles. I once had a Ford dealership manager attempt to inflate my Excursion tires to the recommended pressure (as a courtesy) from the door. I immediately stopped him and he tried to argue/fight me stating he was a Ford Certified blah blah blah and the door says blah blah ...long story shorter is that the truck came with E rated tires and a capacity of about 3600 lbs per tire and I put D rated tires with a load capacity of about 3500 lbs per which to me was not important, but the D rated tires have a maximum inflation of 50psi whereas stock E rated tires were rated to 80psi with a factory recommendation of 65psi.

You SHOULD not attempt to put 65psi into a tire with a max of 50 regardless what the dang door sticker says.

Another way to measure YOUR car is to use chalk and color a good portion across the tread and roll car 2-3 tire rotations and check. If chalk is not evenly worn off, then in/deflate to fix. It works best on a hill so u can gently let the car roll on its own. Straight paths only.

I keep the Sol at 33-35 psi
 

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Taz-
Your lar looks awesome. THe wheels really bring the stripes together. I think a black windshield surround and possibly black tulip panel? The silver thing between the waterfall and the trunk.

Either way, nice job!
 

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Thanks I appreciate the input. The stripes actually look better in real life because the Carbon fiber doesn't really show well in pictures. I was not sure on the wheels because I am more a Chrome bling person but the black seemed to work so I went with it. Only thing I can say I don't like about the car so far is it tends to make it hard to get my house stuff done. It is a BAD INFLUENCE because it always wants to be driven. LOL
 

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One question for anyone running the 245/45ZR-18 Continental ExtremeContact DW XL what are you running for tire pressure?

View attachment 20814

View attachment 20815

View attachment 20816

Thanks again!:)
Love that look, very nice. I'd love to have one just like that to match my Bronco's black/white, black/chorme wheels look.

No and no. That figure is set for the OEM tires. Different tire make/models (and different tire constructions) require different pressures.

For my Conti DWS's I found that 29PSI was WAY under-pressure. The tires squeal on corners and feel soggy and heavy. So I tested the temperatures across the width of the tires with an IR thermometer after some spirited driving and found the temps in the middle of the tires several degrees lower than the edges, supporting the low pressure assumption. I did a few experiments and found that 33-35PSI was 'just right' for my tires.

Since then I found this formula you can try for your tires over on KappaPerformance (coutesy of Critterman): At what pressure do I run my replacement tires at - A formula. Plug in the parameters from YOUR tires and go from there!
On your testing, was this running "spirited" in a straight line, or around curvy roads and then a quick test? I'd think you'd have higher readings on the outers first if it was curvy, then middle, then innard. Straight road at a higher speed would be my preference for seeing a contact patch with daily driving, checking all 3 zones again.

That formula would be just fine to get someone in the ballpark of where to run a tire. I will say it said something about coming from a truck site, so you have to remember there are known and unknown variables here, ok? Known variables:

it asks for gross vehicle weight (even apx. is fine if you are close)
Tire max load
Tire max pressure

I'll have to go back and look at the formula now that I am typing this, but the unknown here is why 35% was chosen from the "truck" site? All this formula is doing is looking at vehicle weight, dividing it up amongst the tires, and applying the variable as a % against the max. to come up with apx. what the tire PSI should be run at....which should provide good contact/long, even life, not necessarily performance, road feel, etc. YOU go from there. Butttt, being a truck site, we often deal in higher percentages/higher psi due to towing, load hauling, etc. so that variable might not be a good one to use for a little sports car, probably should adjust that a little.
 

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One question for anyone running the 245/45ZR-18 Continental ExtremeContact DW XL what are you running for tire pressure?

View attachment 20814

View attachment 20815

View attachment 20816

Thanks again!:)
Love that look, very nice. I'd love to have one just like that to match my Bronco's white/black, black/chrome wheels look.

No and no. That figure is set for the OEM tires. Different tire make/models (and different tire constructions) require different pressures.

For my Conti DWS's I found that 29PSI was WAY under-pressure. The tires squeal on corners and feel soggy and heavy. So I tested the temperatures across the width of the tires with an IR thermometer after some spirited driving and found the temps in the middle of the tires several degrees lower than the edges, supporting the low pressure assumption. I did a few experiments and found that 33-35PSI was 'just right' for my tires.

Since then I found this formula you can try for your tires over on KappaPerformance (coutesy of Critterman): At what pressure do I run my replacement tires at - A formula. Plug in the parameters from YOUR tires and go from there!
On your testing, was this running "spirited" in a straight line, or around curvy roads and then a quick test? I'd think you'd have higher readings on the outers first if it was curvy, then middle, then innard. Straight road at a higher speed would be my preference for seeing a contact patch with daily driving, checking all 3 zones again.

That formula would be just fine to get someone in the ballpark of where to run a tire. I will say it said something about coming from a truck site, so you have to remember there are known and unknown variables here, ok? Known variables:

it asks for gross vehicle weight (even apx. is fine if you are close)
Tire max load
Tire max pressure

I'll have to go back and look at the formula now that I am typing this, but the unknown here is why 35% was chosen from the "truck" site? All this formula is doing is looking at vehicle weight, dividing it up amongst the tires, and applying the variable as a % against the max. to come up with apx. what the tire PSI should be run at....which should provide good contact, and long, even life, not necessarily performance, road feel, etc. YOU go from there. Buttt, that variable is 35%. So if you are dividing weight among 4 tires that's 25%, so this builds in a safety factor, it still makes sense though running this calc with other vehicles I own and the pressures I run the tires at.

The calc should read (W *.35/Y) * Z = psi to run

W= weight of vehicle gross (running weight of car plus anticipated passenger/cargo)
.35 is divvy up amongst 4 tires, so notice it's not 25% and also assumes each tire sees the same weight)
Y= max load stated on tire
Z = max psi stated on tire

W is where you can play with adjusting the outcome of the results:

If my coupe is 3018 lbs
(3018*.35/1565)44= 29.7lbs

If coupe is 3200 lbs (person in it)
(3200*.35/1565)44= 31.48 lbs

ANY tire change is going to change Y and Z most likely and affect the outcome as to where you should start playing around with base psi and adjust to your driving/liking.
 

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Sorry I'm late to the party. What brand, model and size wheels are they? They look fantastic.
 
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