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My tire "guy" at Discount tire ran some numbers for me for my purchase. Going by weight (load) distribution at the corners, etc. etc.

He said my stock 17" on my EX should be at 33 PSI. After crunching the numbers for my 245/40-19s, he said the minimum PSI should be 33 and the MAX should be 36.

I don't know what these numbers mean exactly, but he said with the stock at 33 PSI, the load at the corners is at 1330. With the new tires at 36 that would be 1363.
Hmm.. The recommended PSI for stock 18s are at 35 IIRC and I always ran mine at 40 for better fuel economy and better tire wear and I had no issues.
 

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Hmm.. The recommended PSI for stock 18s are at 35 IIRC and I always ran mine at 40 for better fuel economy and better tire wear and I had no issues.
The load index on the 245/40-19's are higher, so you don't have to run as much pressure. I used the tire pressure calculator posted by ohiomoto a few posts up and it also said for my 245/40-19 to run 34 psi. The load index on my new 245/40's is 98w xl, and my old 215/55/-17 is a 93v.

I'm sure you can run more psi then that, just like you would for stock tires.
 

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I'm not the best when it comes to configuring wheels.. So hopefully some of you wheel heads will be able to help me out.
I'm debating between two different setups.. the first (Wheel/Tire/Offset):
20x9 - 225/35/20 - 38et all the way around (I want to stretch my tires a bit on this setup so I can get as flush as possible to the fender(s).

or

Front: 20x9 - 225/35/20 - 38et
Rear: 20x10 - 245/35/20 - offset?

I really want to run the second setup because I want a concave look to the rear wheels. I don't believe the concavity of the wheels will be as noticeable on a 20x9 wheel as it would be on a 20x10. -Correct me if I'm wrong. My problem is determining offset for the rear on a 20x10 wheel. What offset would I need to run on the rear wheels to tuck it under the fender and have enough poke from the wheel to make it flush?
 

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2019 Mercedes-Benz Sprinter 170
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I'm not the best when it comes to configuring wheels.. So hopefully some of you wheel heads will be able to help me out.
I'm debating between two different setups.. the first (Wheel/Tire/Offset):
20x9 - 225/35/20 - 38et all the way around (I want to stretch my tires a bit on this setup so I can get as flush as possible to the fender(s).

or

Front: 20x9 - 225/35/20 - 38et
Rear: 20x10 - 245/35/20 - offset?

I really want to run the second setup because I want a concave look to the rear wheels. I don't believe the concavity of the wheels will be as noticeable on a 20x9 wheel as it would be on a 20x10. -Correct me if I'm wrong. My problem is determining offset for the rear on a 20x10 wheel. What offset would I need to run on the rear wheels to tuck it under the fender and have enough poke from the wheel to make it flush?
Here's what I can tell you. First, offset is offset. Rim width doesn't change where the tread lines up inside the fender. This means that the tread of a 245 tire on a 10" rim will be the same as it is on a 9" wheel if the wheels have the same offset. But the sidewall comes into play on a stretched tire. Since the max rim width for a 245 is 9.5" and the sidewall will be less than 3.5", you will be stretching the tire a good bit. So it would be nice to know how much room you have between the wheel and fender when the suspension is fully compressed.

I used a 245 on a an 8.5" wheel with a 40mm offset without issues. Using that as a baseline, you can assume the tread will clear on a 10" wheel with a 40mm offset but you will have 3/4" more poke. Now, you need to figure out a few things. First, will the tire actually stretch all the way to the outer edge of the wheel or will it leave the bead of the wheel exposed? This affects the amount of stretch. If the tire sits inside of the outer edge of the wheel it will be no more stretched that if it where on a wheel almost 1" narrower. Second, will the sidewall clear the fender when the suspension is fully compressed? Third, are able/willing to adjust camber, change springs, buy coilovers, roll the fenders or buy new wheels if you need to? Also, what do you want the wheel/tire to look like? Do you want maximum poke and stretch or just want the concave wheel to fit?

I would look at some of the setups on to get an idea of what will work or seek advise from a wheel shop that does a lot of this kind of work. My guess is that you'll have no issues with a ET42 or higher. If you want poke try to keep it at 45mm or less. If you want less stretch, think about a wider tire on the 10" wheel and increase the offset as needed.
 

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I have a staggered set of wheels off my last car (BMW 335i) that I think will be too wide for the SX, but wanted to get a opinion on. They are 19x9.5 ET40 5x114.3 and 19x8.5 ET30 5x112. I want to get the stretched look but think even if I roll the fenders and go with a 225/245 combo, I would still have issues. The car is staying stock height. Thoughts?
 

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I have a staggered set of wheels off my last car (BMW 335i) that I think will be too wide for the SX, but wanted to get a opinion on. They are 19x9.5 ET40 5x114.3 and 19x8.5 ET30 5x112. I want to get the stretched look but think even if I roll the fenders and go with a 225/245 combo, I would still have issues. The car is staying stock height. Thoughts?
It would probably work fine if you are talking about a if the profile or aspect ratio of the tires are 35 or 40. But I don't think the bolt pattern will be correct. As nuke0907 pointed out, you should have a 5x112 bolt pattern on all 4 wheels if they were on a BMW and you need a set of 5x114.3 for the Kia.
 

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Sorry about that... They are all 5x114.3. I think I am just going to try them on and see how it looks. I need a set of tires on them so was hoping if I went with the stretched look it would work beacuse i love these wheels. I had a 245/ 275 tire setup on them with the BMW. I know there's no way I can do that with this car.


What's the general guideline for stretched tires? Would I go with a 225/245 setup for a 8.5/9.5 width rim combination?
 

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I had 225/40-19 on 19x8.5" et35 wheels and you should have no issues there. At one used a set of 245s on 19x8.5 et40 wheels and had no issues in the back You might be able to squeeze a 255/30 in there but it will be real close. The nice thing about the 225/40 - 255/35 combo is that they have the same sidewall height. The 245/40 is a little taller.
 

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Hey guys, I'm hoping I can get some input here. Just bought a set of 20x8" wheels with a 35 offset. I've narrowed it down to either 235/35/20 or 225/35/20. I may lower in the future but it won't be a drastic lowering. Less than an inch on each side. Which tire would be better? I was leaning towards the 235 because I hate the stretched tire look and I'm worried about curbing. Any suggestions would be appreciated.
 

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Best curb protection would be to go with a good amount of carefull driver :)

With that, 35% sidewall wont save the wheel from curbs.

So go with what will give u the look or ride u want!

Neither of those are even close to stretching.so its just personal preference.
Check the wheel picture thread to find both those specs and maybe brand u want and see them to help u choose
 

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Like Jammin said, you will be fine with either one. I'm running 20x8.5 35 offset wanted to go with 235s but they got backordered so I went with 245s, still no curb protection. I don't care for a lot of stretch either so going 245s was not that big a deal. Go 235s and be careful, a drop should be no problem. I'm going to be real close if lowered.
 

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So if i run 20x8.5 up front with a 235/35/20 and a 20x10 in the rear with a 245/35/20 on stock
with no suspension mods I shouldn't rub right? I think the offset is +40 or 46...

Thanx
 

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So if i run 20x8.5 up front with a 235/35/20 and a 20x10 in the rear with a 245/35/20 on stock
with no suspension mods I shouldn't rub right? I think the offset is +40 or 46...

Thanx
no suspension mods it wont rub at all with either offset. when you lower it with ET46 it might not rub either. ET 40 on 20x10 with 245 will rub when you lower but you can add some camber to fix that. front setup is fine with no issues.
 

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Lots of good info here, but what is missing is the tire load index and speed ratings, like 95V on my stock SX.
As I consider wider and taller tires next time, I wondered what the min would be.
It turns out to be 93 for load index for a turbo ex, IIRC. As for speed, that is up to you.
If it is less than that, beware for ride and safety.
 

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will 245/35 fit a 20x8 wheel or is the 235/35 best bet?...I have a 2013 LX and not loweing it but is currently sitting on some 20" Avenue a604 in black 40+mm offset on 225/35/20 want to go a lil wider and in turn a lil taller so dunno which tire size to go with and dunno if a 245 will even fit an 8" wheel...any info is greatly appreciated thanks!
 

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Hey guys. Quick question. Would 19x8.5 et45 work in the front if Im lowered on coils? I have no finger gap all arounf right now and i currently have 19x8.5 et35 in the front but to make it work, i have to have it a little more than -2 camber to not rub against the bolt that holds the bumper to the fender and it does wear my tire out in the inside faster than the outside at the end of front tires life. Thanks in advance everyone.
 
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