Wheels and tires 101
#1
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Wheels and tires 101
Gang,
There are many things about tires and wheels I don't know and I think I'm not alone so I'm starting this thread as an education thread with a post I'm copying from another thread.
Explanation of the numbers on your tires:
245/40/19 is our example.
245, 275, that's the WIDTH of the tires in mm. so 245 means a tire that's 245mm wide.
the second number is the sidewall height, which is a % of the width.
the third number is the diameter of the RIM that the tire will fit on.
so for example, 245/40/18, that means the tire is 245mm wide, the sidewall is 245 x 0.40 = 98mm, and it's for 18" wheels. if you add everything together, i think the overall diameter of the wheel will be around 26"
now say you go to 19" wheel, you need 245/35/19. that means the tire is still 245mm wide, but the sidewall is not 245 x 0.35 = 85.75mm (instead of 98mm), and it's for 19" wheel. if you add everything together, the overall diameter is around 26" again
the goal is to have the overall diameter of the wheel being about the same as stock, that way the speedo will not be off. so just another example, if you get 20" wheel, the tire will be 245/30/20, if you want to stay with the same overall diameter
and 275/30/19 is not a missprint. that's a tire of 275mm width (much wider than 245), and the sidewall ratio is 30% (instead of 35%). since the tire is wider, although the % is lower, but if you do the math, the sidewall height will be very similar to that of the 245/35/19. try to do it, you will understand
and as long as you get wheels that's of the right offset, width, and also get tires of the right spec, you are good to go.
There are many things about tires and wheels I don't know and I think I'm not alone so I'm starting this thread as an education thread with a post I'm copying from another thread.
Explanation of the numbers on your tires:
245/40/19 is our example.
245, 275, that's the WIDTH of the tires in mm. so 245 means a tire that's 245mm wide.
the second number is the sidewall height, which is a % of the width.
the third number is the diameter of the RIM that the tire will fit on.
so for example, 245/40/18, that means the tire is 245mm wide, the sidewall is 245 x 0.40 = 98mm, and it's for 18" wheels. if you add everything together, i think the overall diameter of the wheel will be around 26"
now say you go to 19" wheel, you need 245/35/19. that means the tire is still 245mm wide, but the sidewall is not 245 x 0.35 = 85.75mm (instead of 98mm), and it's for 19" wheel. if you add everything together, the overall diameter is around 26" again
the goal is to have the overall diameter of the wheel being about the same as stock, that way the speedo will not be off. so just another example, if you get 20" wheel, the tire will be 245/30/20, if you want to stay with the same overall diameter
and 275/30/19 is not a missprint. that's a tire of 275mm width (much wider than 245), and the sidewall ratio is 30% (instead of 35%). since the tire is wider, although the % is lower, but if you do the math, the sidewall height will be very similar to that of the 245/35/19. try to do it, you will understand
and as long as you get wheels that's of the right offset, width, and also get tires of the right spec, you are good to go.
#3
exclusive matchup
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thread like these are good. i will probably keep them here for now, over time i will probably move them over to the tires/wheels forum, which is more generic
regarding your second question on lip. a lot of aftermarket wheels they have lips right? there are two type, stepped and reverse.
the reverse lip is probably the "normal" lip setup most people have seen so far. it's just a big flat lip. so someone says he got a 4" reverse lip in the back, then you will see a flat 4" wide lip. that's easy
stepped is the other kind of setup. which is, instead of a flat lip, there is actually a step in between. the part of the lip that's closer to the center face of the wheel, it's a bit higher than the outside, creating a "step" look.
that's the difference between the two.
for the definition of offset and so, read my sticky thread here:
https://www.clublexus.com/forums/sho...d.php?t=175288
when i have enough information on the sc430 setup, i will probably add that to the content as well
regarding your second question on lip. a lot of aftermarket wheels they have lips right? there are two type, stepped and reverse.
the reverse lip is probably the "normal" lip setup most people have seen so far. it's just a big flat lip. so someone says he got a 4" reverse lip in the back, then you will see a flat 4" wide lip. that's easy
stepped is the other kind of setup. which is, instead of a flat lip, there is actually a step in between. the part of the lip that's closer to the center face of the wheel, it's a bit higher than the outside, creating a "step" look.
that's the difference between the two.
for the definition of offset and so, read my sticky thread here:
https://www.clublexus.com/forums/sho...d.php?t=175288
when i have enough information on the sc430 setup, i will probably add that to the content as well
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more questions, guess I'm the only one who needs this education:
- When I see 20x8.5 I know what the 20 means, what does the 8.5 mean?
- I see a lot of cars that have 20x8.5 in the front run 20x10 in the back why?
- Is there a benifit to a multi-piece wheel?
- I typically don't get chrome wheels because I hear they require much more care and in areas where there is snow the salt will do real damage to them. Is this true?
- When I see 20x8.5 I know what the 20 means, what does the 8.5 mean?
- I see a lot of cars that have 20x8.5 in the front run 20x10 in the back why?
- Is there a benifit to a multi-piece wheel?
- I typically don't get chrome wheels because I hear they require much more care and in areas where there is snow the salt will do real damage to them. Is this true?
#7
The One
iTrader: (3)
Originally Posted by Addiction2
- When I see 20x8.5 I know what the 20 means, what does the 8.5 mean?
Originally Posted by Addiction2
- I see a lot of cars that have 20x8.5 in the front run 20x10 in the back why?
Originally Posted by Addiction2
- Is there a benifit to a multi-piece wheel?
Originally Posted by Addiction2
- I typically don't get chrome wheels because I hear they require much more care and in areas where there is snow the salt will do real damage to them. Is this true?
Trending Topics
#8
rim depth
Here we go again!
So if you have different rim depths, say 9 in the front and 10 in the back is there a visual difference of where the rubber meets the rim or does the 275 instead of the 245 compensate for this?
So if you have different rim depths, say 9 in the front and 10 in the back is there a visual difference of where the rubber meets the rim or does the 275 instead of the 245 compensate for this?
#10
The One
iTrader: (3)
Originally Posted by camillian
So if you have different rim depths, say 9 in the front and 10 in the back is there a visual difference of where the rubber meets the rim or does the 275 instead of the 245 compensate for this?
The width of a tire when mounted on a rim with a particular width can be visually different. Some will fit comfortably and some will seem flatter as the tire is stretched out. The latter is when a tire width is slimmer than the rim width.
What are you asking in terms of this "visual difference"?
#11
Yes that's it.
So finally if the overall diameter of a rim and tire combined remains pretty much the same as stock (around 26" when upgrading from a 18" to a 19" or even 20" rim because tire height gets reduced. Why does it look like the 20" fills in the space more than the 18". (diameter not depth). I mean when standing back from the car at a side profile the gap around thIe wheel well looks filled up with the 20" as opposed to the 18" where it looks like you can fit atleast 4 fingers. Is this an illusion or are these cars just lowered?
I want to thank everyone for their patience.
Mario
So finally if the overall diameter of a rim and tire combined remains pretty much the same as stock (around 26" when upgrading from a 18" to a 19" or even 20" rim because tire height gets reduced. Why does it look like the 20" fills in the space more than the 18". (diameter not depth). I mean when standing back from the car at a side profile the gap around thIe wheel well looks filled up with the 20" as opposed to the 18" where it looks like you can fit atleast 4 fingers. Is this an illusion or are these cars just lowered?
I want to thank everyone for their patience.
Mario
#12
Originally Posted by camillian
So finally if the overall diameter of a rim and tire combined remains pretty much the same as stock (around 26" when upgrading from a 18" to a 19" or even 20" rim because tire height gets reduced. Why does it look like the 20" fills in the space more than the 18". (diameter not depth). I mean when standing back from the car at a side profile the gap around thIe wheel well looks filled up with the 20" as opposed to the 18" where it looks like you can fit atleast 4 fingers. Is this an illusion or are these cars just lowered?
Mario
Mario
and the wheel tend to come closer to the outside.
Factory wheels are tucked in when aggressive aftermarket setups sit very close to the fender
arch, I guess that is why the illusion happens.
Speaking about the benefit of a multi-piece wheel, another point would be that you can choose
from a wider range of variation.
3 piece wheels are composed of an outer rim, inner rim and center disk, usually wheel
manufacturers carry several size specs of each piece and you can combine these to get
the best setup for your specific vehicle.
The concern about salt and harsh weather is true.
But that is not a problem just for chrome wheels, it gives damage to any kind of finish.
I also hear problems when you clean your wheel with some kind of cleaner but it isnt rinsed
enough and the cleaner remains on the surface leaving a stain when it dries off.
I personally think that is the worst and ironic thing you could possibly do as to damage the
wheel when you meant to clean it.
So I'd say its not the color of wheel or where you live, its how much you care about the wheel
#13
rims don't fit?
Wow I went to another shop like Rominl said.
This guy told me the Opera 2 PL by OZ in 19 and 20" are for Audi and mercedes fit only. The Opera 1 PL which only comes in 18" fit lexus.
That would be 18x 8 with +35 offset front and rear. I know the 18 x 8 is factory but what about the +35 offset. Is that also the same or does it come out a bit more?
Can I make these wheels work by going 245/40/18 in the front same as factory and maybe play with the numbers in the back. Say 265/35/18 and add some spacers to bring them out a bit. Can I go with a wider tire in the back if the rim depths are the same all around at 8"
These wheels are too good of a deal to pass up and they are alot nicer than the factory ones even though they are the same size?
Thanks,
Mario
This guy told me the Opera 2 PL by OZ in 19 and 20" are for Audi and mercedes fit only. The Opera 1 PL which only comes in 18" fit lexus.
That would be 18x 8 with +35 offset front and rear. I know the 18 x 8 is factory but what about the +35 offset. Is that also the same or does it come out a bit more?
Can I make these wheels work by going 245/40/18 in the front same as factory and maybe play with the numbers in the back. Say 265/35/18 and add some spacers to bring them out a bit. Can I go with a wider tire in the back if the rim depths are the same all around at 8"
These wheels are too good of a deal to pass up and they are alot nicer than the factory ones even though they are the same size?
Thanks,
Mario
#14
You're already pushing the tire limit with a 245 tire on an 8" wheel IMHO, so you'd have to stick to stock tire size. My sincere opinion is 'why bother'.
If you insist in size 18" for ride reasons, at least go wider on the rear. I'd also ask here if the offset is not problematic. One reason I don't like to fit my cars with aftermarket wheels is the additional offset (wheels pushed out to the corners). Car looks great, but the additional stress on the suspension might be a problem in the long run, and who knows if the warranty would cover such thing. Since I'm not into 'cheating', and putting back stock tires if something happens, I just stick to stock. Certainly wish our car was like BMWs (with sport package) from the factory; they fit perfect from the factory, and most wheel designs are great looking too.
JC
If you insist in size 18" for ride reasons, at least go wider on the rear. I'd also ask here if the offset is not problematic. One reason I don't like to fit my cars with aftermarket wheels is the additional offset (wheels pushed out to the corners). Car looks great, but the additional stress on the suspension might be a problem in the long run, and who knows if the warranty would cover such thing. Since I'm not into 'cheating', and putting back stock tires if something happens, I just stick to stock. Certainly wish our car was like BMWs (with sport package) from the factory; they fit perfect from the factory, and most wheel designs are great looking too.
JC