Okay, so this is the 4 millionth thread on tires, but I guess when we're all ready to plunk our cash down we want to get all the opinions besides our own, especially when you plan to buy the tires from tirerack where they are not the sharpest axes in the shed when it comes to information (at least in my experience).
I'm adding these tires to a set of 17" rims I picked up and I want to get the 97' handling better (I know, the ugly step sister Q but she's mine and paid for!). Here are the choices that I've narrowed it down to in the prices ranges I can afford, all in 245/45 17 size:
BF Goodrich G-Force TA YR Rated for $177Bridgestone S-03 YR Rated for $181Yokohama AVS Sport WR rated for $146Kumho ECSTA Supra WR rated for $98
I know there are others, I'm not going over $190 per tire so the Michelins are out. I was leaning towards the S-03's but I had a friend tell me he thought that Kumho's are just as good just not a well known name.
What do you guys think??
97 Q45 Tire Selection
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greg_atlanta
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I've always been a Yokohama fan, but my beloved AVS Intermediate aren't available in your size anymore. Looks like they were replaced by the AVS ES100, 280 treadwear (kinda soft). They're only $109 each.
I think you should stay near the $100 mark. If you buy $175 tires, you'll try to make them last forever (and have 10,000 miles of poor performance). If you buy $100 tires, you don't feel bad tossing them after 20,000 miles and trying something else.
The AVS sport and Bridgestones are 51 max psi, and that usually means the sidewall is weaker and more damage prone??
Some of the techs at T-3 are big on Sumitomo, good for the money. Not sure which tire though, several in that size.
I think you should stay near the $100 mark. If you buy $175 tires, you'll try to make them last forever (and have 10,000 miles of poor performance). If you buy $100 tires, you don't feel bad tossing them after 20,000 miles and trying something else.
The AVS sport and Bridgestones are 51 max psi, and that usually means the sidewall is weaker and more damage prone??
Some of the techs at T-3 are big on Sumitomo, good for the money. Not sure which tire though, several in that size.
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Q45tech
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"I want to get the 97' handling better "Since the 97Q came with tires that were 200 treadwear index, anything harder will diminish handling. Sure going to a wider or stiffer sidewall will help a little [in the feel department] and you can probably trade a little hardness [220-260] for width and end up with the same oem real handling [peak G's in a slalom].
I believe the oem tire was a 94V so select a tire that has a higher load index [95,96,97,98 maximum carrying load index] .....roughly half of the extra load rating in pounds can be translated to a percentage increase.for example: 1640/1521= 1.078 so the extra strength will allow a 8% lower slip angle under equal load....this means that a 4% increase in cornering power is obtainable.....0.8G x 1.04= 0.83G.
Apples to apples a very soft 15" tire can out handle a hard 17" tire of the same treadwidth and diameter even more so if the 15" has a higher load index.Sure the 17" will feel better in turn in [stiffer sidewall] but it is just a feel not necessarily a measurable G number. A lot depends on the drivers ability to handle a less forgiving tire.
Remember the actual tread patch area is always the same [in square inches] based on vehicle weight.......a wider tire has a wider but narrower lengthwise patch......1200 pounds on a 44 psi tire means the patch is always 27.2727 square inches.
The tread and sidewall area is what dissapates the frictional heat which controls the C of F.
I believe the oem tire was a 94V so select a tire that has a higher load index [95,96,97,98 maximum carrying load index] .....roughly half of the extra load rating in pounds can be translated to a percentage increase.for example: 1640/1521= 1.078 so the extra strength will allow a 8% lower slip angle under equal load....this means that a 4% increase in cornering power is obtainable.....0.8G x 1.04= 0.83G.
Apples to apples a very soft 15" tire can out handle a hard 17" tire of the same treadwidth and diameter even more so if the 15" has a higher load index.Sure the 17" will feel better in turn in [stiffer sidewall] but it is just a feel not necessarily a measurable G number. A lot depends on the drivers ability to handle a less forgiving tire.
Remember the actual tread patch area is always the same [in square inches] based on vehicle weight.......a wider tire has a wider but narrower lengthwise patch......1200 pounds on a 44 psi tire means the patch is always 27.2727 square inches.
The tread and sidewall area is what dissapates the frictional heat which controls the C of F.
[QUOTE]Originally posted by Q45tech [Remember the actual tread patch area is always the same [in square inches] based on vehicle weight.......a wider tire has a wider but narrower lengthwise patch
I'm having trouble getting my mind around this concept. Wouldn't this be true for the same width wheel, but wouldn't a wider wheel permit a larger contact patch? I'm imagining a very skinny tire on a narrow wheel vs a very wide tire on a commensurately wide wheel. It doesn't seem like the skinny one would mash down far enough to equal the wide set up's contact patch.
I'm having trouble getting my mind around this concept. Wouldn't this be true for the same width wheel, but wouldn't a wider wheel permit a larger contact patch? I'm imagining a very skinny tire on a narrow wheel vs a very wide tire on a commensurately wide wheel. It doesn't seem like the skinny one would mash down far enough to equal the wide set up's contact patch.
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Q45tech
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Sure a wider wheel has [could allow] a wider tread but Geometry is geometry [finding the area of different shapes].The pressure on the tread is generally fairly equal except at the extreme edges [where the side wall connects to the tread.
The air pressure [from 25-44 psi] controls the shape obviously the VOID areas are not in contact with the road only the rubber portion."Tyre width has no direct relation to the amount of grip generated; it is a secondary factor, and the width basically relates to cooling potential and so the tyre compound that can be used. The size of the contact patch has no bearing on the amount of grip generated at all, apart from the extreme of where the compound is getting so hot that it no longer acts as a solid (and therefore doesn't follow Amonton's Law). The tyre pressure has no direct bearing on the level of grip (apart from aquaplaning), but it does have a bearing on the heating and cooling characteristics of the tyre. Having a lower tyre profile gives improved handling through reduced sidewall stress and improved contact patch shape stability."
http://www.autospeed.com/A_0996/page1.html
So much of the hype about 17-18-19" wheels is non sense and a marketing ploy to equate SIZE with performance.....what a wonderful thing figuring out how to SELL $300 tires to go on $1,000 each wheels that fail soon so you can sell another set.
Much of the BIG wheel, Big shoe, Big other things myth seems to be related.
Car manufacturers have just gone along with what the public wants
The air pressure [from 25-44 psi] controls the shape obviously the VOID areas are not in contact with the road only the rubber portion."Tyre width has no direct relation to the amount of grip generated; it is a secondary factor, and the width basically relates to cooling potential and so the tyre compound that can be used. The size of the contact patch has no bearing on the amount of grip generated at all, apart from the extreme of where the compound is getting so hot that it no longer acts as a solid (and therefore doesn't follow Amonton's Law). The tyre pressure has no direct bearing on the level of grip (apart from aquaplaning), but it does have a bearing on the heating and cooling characteristics of the tyre. Having a lower tyre profile gives improved handling through reduced sidewall stress and improved contact patch shape stability."
http://www.autospeed.com/A_0996/page1.html
So much of the hype about 17-18-19" wheels is non sense and a marketing ploy to equate SIZE with performance.....what a wonderful thing figuring out how to SELL $300 tires to go on $1,000 each wheels that fail soon so you can sell another set.
Much of the BIG wheel, Big shoe, Big other things myth seems to be related.
Car manufacturers have just gone along with what the public wants
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Q45tech
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Of course you need larger diameter wheels for bigger diameter brake rotors but Nissan has generally been lacking [until recently]in going to large rotors since they don't improve single normal stop braking distance [60 to zero] but now that mags have started testing from 80 or 100 mph they are moving into the 90's finally.
Autospeed
I've noticed a couple of articles from the Austrailian on-line magazine http://www.autospeed.com quoted on the list. Those of you who haven't looked, check it out.
This looks like an on-line format that just might work. I would like to see a US equivalent. As it is, its fun to see the cars they have in the land of oz and what they do to them. We are not the only ones addicted to speed.
This looks like an on-line format that just might work. I would like to see a US equivalent. As it is, its fun to see the cars they have in the land of oz and what they do to them. We are not the only ones addicted to speed.
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BadQ45t
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Well Q45Tech no sure if I know the take-away from your advice, I have purchased the 17" rims and plan to install them and keep my old stock OEM rims just in case. I think I will take the advice from above and give the Kumho's a try, at 400 and change delivered it is hard to beat the value.
I think I'm going to try the S-03's on my 15" stock 84' 300ZX, the old Bridgeston RE71's are finally getting bald on the sunday driver and I want try those out somewhere (since it is a sunday car it gets maybe 3-4k a year so tires last a long time).
I think I'm going to try the S-03's on my 15" stock 84' 300ZX, the old Bridgeston RE71's are finally getting bald on the sunday driver and I want try those out somewhere (since it is a sunday car it gets maybe 3-4k a year so tires last a long time).
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AZhitman
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At some point this gets ridiculous. Not to dispute what Dennis is relating by any means, but the treadwear numbers are RELATIVE only within the brand. In other words, theoretically, a 340 treadwear brand A tire could be the same "hardness" as a 200 treadwear brand B tire. So many Q's out there are running around on skinny, hard tires... Sad that they're missing out.
My new 245/50/16 Yoko's are a 96V with a 400 treadwear rating (Traction AA, Temp A) and outperformed the highly-recommended BFG KDWS of the same size. I intend to replace them at around 20K, regardless of their wear.
If there's a Discount Tire store in your area, you can get a set of those in that size for around $100 each. I've enjoyed putting the first 2K miles on 'em... So that's my recommendation for what it's worth.
My new 245/50/16 Yoko's are a 96V with a 400 treadwear rating (Traction AA, Temp A) and outperformed the highly-recommended BFG KDWS of the same size. I intend to replace them at around 20K, regardless of their wear.
If there's a Discount Tire store in your area, you can get a set of those in that size for around $100 each. I've enjoyed putting the first 2K miles on 'em... So that's my recommendation for what it's worth.
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Q45tech
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Quite easy to compare the rubber compound hardness with a Shore Durometer. As each hot cold cycle makes them harder and harder and harder and harder!http://www.racerpartswholesale.com/long ... 21-tc.html
Generally the practice of buying AS tires just before Summer is counterproductive since the summer heat fries the rubber making it significantly worse [harder] for winter [cold] driving when you need soft the most.
The point I was making is that generally oem tires are soft BECAUSE mileage is not a factor [within reason] and the factory is only interested in showing off good braking [wet and dry] and handling numbers for magazines.....coupled with what ever ride standards are appropriate for the class of vehicle. Everybody involved in the tire business knows there are trade off.
Since most people don't want REAL performance tires but desire low cost and long life......the higher numbers are more suspect than the lower ones.
The problem with tread wear index is that it is extrapolated from the 8,000 mile runs on the Texas Highway Test Track and only shows a relative number compared to other tires in a single company's line......but with lower numbers [100-220] in all likelyhood you are getting a soft tire -- as to my knowledge there has never been a race to see who can make the FASTEST wearing passenger tire!If you are doing around town driving only [without significant extended highway] these index numbers mean little or nothing!Since agressive turning, braking, and WOT acceleration are what wear tires not 20,000 miles at a steady 70 mph [assuming the aligment is correct].
Sometimes the least expensive 17" is good enough especially if you change them every 10,000 miles instead of trying to get 20,000 out of them. Since on a wider tire tread depth is very important in turning in the rain at least till the standing water exceeds the depth then the compound softness takes over as the limiting parameter.
I subscribe to this policy if tire rack is having a special on an obsolete model [that had a good reputation in the past] I jump on it knowing that at half price 10-15,000 miles is getting my moneys worth.
It would be great if TireRack would do some half worn wet tests on the same tires they tested new but I doubt they could get their drivers to do it for safety reasons.
Remember the US DOT reported that over 66% of the tires currently sold will not meet the new proposed safety standards when brand new. So my guess is less than 10% will do so when half used!http://www.rma.org/newsroom/20...s.pdf
Generally the practice of buying AS tires just before Summer is counterproductive since the summer heat fries the rubber making it significantly worse [harder] for winter [cold] driving when you need soft the most.
The point I was making is that generally oem tires are soft BECAUSE mileage is not a factor [within reason] and the factory is only interested in showing off good braking [wet and dry] and handling numbers for magazines.....coupled with what ever ride standards are appropriate for the class of vehicle. Everybody involved in the tire business knows there are trade off.
Since most people don't want REAL performance tires but desire low cost and long life......the higher numbers are more suspect than the lower ones.
The problem with tread wear index is that it is extrapolated from the 8,000 mile runs on the Texas Highway Test Track and only shows a relative number compared to other tires in a single company's line......but with lower numbers [100-220] in all likelyhood you are getting a soft tire -- as to my knowledge there has never been a race to see who can make the FASTEST wearing passenger tire!If you are doing around town driving only [without significant extended highway] these index numbers mean little or nothing!Since agressive turning, braking, and WOT acceleration are what wear tires not 20,000 miles at a steady 70 mph [assuming the aligment is correct].
Sometimes the least expensive 17" is good enough especially if you change them every 10,000 miles instead of trying to get 20,000 out of them. Since on a wider tire tread depth is very important in turning in the rain at least till the standing water exceeds the depth then the compound softness takes over as the limiting parameter.
I subscribe to this policy if tire rack is having a special on an obsolete model [that had a good reputation in the past] I jump on it knowing that at half price 10-15,000 miles is getting my moneys worth.
It would be great if TireRack would do some half worn wet tests on the same tires they tested new but I doubt they could get their drivers to do it for safety reasons.
Remember the US DOT reported that over 66% of the tires currently sold will not meet the new proposed safety standards when brand new. So my guess is less than 10% will do so when half used!http://www.rma.org/newsroom/20...s.pdf
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AZhitman
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Speaking of this topic, Dennis, you had mentioned an "optimal" inflation practice of something like 39/44 front to rear (?). Obviously, since mine say max press 35psi, the tire retailer won't allow me to leave the shop with those numbers, but I have a set of gauges (one digital, one conventional) and monitor my own pressures.
Given the specs for the tires I'm running, what's your cold/hot pressure recommendation (keeping in mind the temps here in the summer).
As always, more great stuff from the Master.
Also, any thoughts on a staggered combo of 255 rears/245 fronts?
Given the specs for the tires I'm running, what's your cold/hot pressure recommendation (keeping in mind the temps here in the summer).
As always, more great stuff from the Master.
Also, any thoughts on a staggered combo of 255 rears/245 fronts?
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Q45tech
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1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
You measure or guess the weight on each tire, then you take the max load and divide by MAX PSI to get a pound of support per psi......1521/35= 43.45 pounds per psiSay each front tire has 1180 so divide by 43.45= 27.15 psi to just support the static weight COLD.
OR 1180/1521=77.5% of 35 equals the same thing 27.15 psi! because the sidewall is stronger and supports weight unlike a 44 psi tire
Now as the tire heats up expect a 3 psi gain or 30-31 psi hot after 20 minutes at speed.
Since the unloaded weight balance is 52/48 each rear tire has 220 less pounds or 160 full of gas no passengers......the rear could be 3-4 psi less [but adjusted upward with trunk junk or rear passengers
But you need to add a fudge factor equal to the amount of weight shift during cornerning/braking you will normally see......for racing the factor would equal the max load 35psi for normal driving maybe 3 psi would be enough so [27+3]= 30 psi cold front 28 cold rear.
I have 1640 load index reinforced 35 psi tires on my front and this [30 psi cold] seems to work best never had lower load rating 35 psi tires on front but you'll just have to start with 32 psi cold and experiment downward
OR 1180/1521=77.5% of 35 equals the same thing 27.15 psi! because the sidewall is stronger and supports weight unlike a 44 psi tire
Now as the tire heats up expect a 3 psi gain or 30-31 psi hot after 20 minutes at speed.
Since the unloaded weight balance is 52/48 each rear tire has 220 less pounds or 160 full of gas no passengers......the rear could be 3-4 psi less [but adjusted upward with trunk junk or rear passengers
But you need to add a fudge factor equal to the amount of weight shift during cornerning/braking you will normally see......for racing the factor would equal the max load 35psi for normal driving maybe 3 psi would be enough so [27+3]= 30 psi cold front 28 cold rear.
I have 1640 load index reinforced 35 psi tires on my front and this [30 psi cold] seems to work best never had lower load rating 35 psi tires on front but you'll just have to start with 32 psi cold and experiment downward
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greg_atlanta
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BadQ45t
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'16 Mercedes Benz S550e V8 Power & 35 MPG - Location: Half Moon Bay, CA
Thanks for the info, I will check them out. I'm actually going to have to buy them in LA since that is where the Rims are sitting, in my mechanic shop. I scored the rims from a guy on this board (maybe he's still around) for 200 bucks but they were in LA. I had my Dad check out the rims, and the guy dropped them off in Marina Del Rey. I've just gotta get the energy now to drive to LA and get them mounted.
Isn't tires.com discount tires in AZ and some other name in LA? I bought plenty of tires from them when I lived in San Diego and than when I did my 3 years in Phoenix (did my doctoral work at Arizona State). I miss AZ but not those summers!
Isn't tires.com discount tires in AZ and some other name in LA? I bought plenty of tires from them when I lived in San Diego and than when I did my 3 years in Phoenix (did my doctoral work at Arizona State). I miss AZ but not those summers!
q45dallas wrote:badq45t, I just got a 99 Q45T, the original tire size 225/50/17 is an odd size and I wanted to change to 245/45/17 but the tire rack rep does not know this size will fit without some rubbing on the fender. Since you got the 245/45/17 on your car, can you tell me does it fit OK. Thank you.
There will be no rubbing.
Fred...
Thank you for the quick response.I just ordered the Sumitomo HTRZ+ from Tire Rack. They called me right away after they received the order to warn me about the size of the tire. Just looking at the car visually, I don't think it should be a problem.The second generation Q may not be as fast or distinctively looking than the first generation but it is still a great car for the money.
BadQ45t wrote:Isn't tires.com discount tires in AZ and some other name in LA? I bought plenty of tires from them when I lived in San Diego and than when I did my 3 years in Phoenix (did my doctoral work at Arizona State). I miss AZ but not those summers!
Tires.com is the same company as Discount iTire n most of the country, and they do business as America's Tire in CA because there already was a "Discount Tire" chain in CA before they started doing business there. I did a double take the first time I walked into an America's Tire when I moved here. It looked very familiar.