Sumitomo HTR Z
Thread Starter
Melting Slicks
Joined: Mar 2008
Posts: 2,453
Likes: 347
From: SC
i am still amaized how people can enjoy this tire. it breaks hard when you're at the limits. traction can be adaquite if you air them down and warm them up. the tires are plain scary in cold weather, better warm. in all honesty they are the worst tire i have ever had on a sports car. my gripe is more based on other available choices than it is in pure hate of the tire. in dry weather applications the falken rt-615 will kill it, simply put. in wet/cold weather the yokohama s-drive will slaughter it. both of those run under $150 a tire in 275 40 17. i've been lucky enough to try a variety of tires on both my corvette and my integra. the sumi is the worst based on non burn out traction, road handling and ease of control at the limit. doing burn outs at 65mph in dry weather on a 315 with a car that only runs 12.3-12.4 just sucks, at least when i'm not trying to. not being able to get on the gas after the apex of a corner also sucked, normally you can transition to the throttle after the apex & blast out of it in my c4 pretty easy. after a few 70mph back end drifts that were not even throttle induced i threw on a pair of nitto 555R's in the same 315. the car is easy to control, doesn't wash out, actually hooks up cold and does not inspire the sense of fear when i drive that the sumi did. that's part of my soap box with the sumi. got me, if you like em, hey, i'm just another guy on the net. i just can't figure out how decent cheap tires like the rt-615 don't get mentioned and the sumis come up frequently.
Race Director
Joined: Jan 2008
Posts: 16,028
Likes: 170
From: oregon
LOL i read the part about not racing, it was just hard for me to process. like a foreign language or something...n-o-t ...race. okay, got it 
i honestly just like seeing people enjoy what they have & if the sumis provide that, all the better. even in a non racing environment i would think that a person would desire the best tire available for your dollar. 315 is a very hard size to buy & i can understand it a bit there since the plain nitto 555 {treadwear 300} is the only other "street" tire being produced. the 555R has a 100 treadwear and extremely small water grooves which i'm sure keeps more than one person away.
i honestly just like seeing people enjoy what they have & if the sumis provide that, all the better. even in a non racing environment i would think that a person would desire the best tire available for your dollar. 315 is a very hard size to buy & i can understand it a bit there since the plain nitto 555 {treadwear 300} is the only other "street" tire being produced. the 555R has a 100 treadwear and extremely small water grooves which i'm sure keeps more than one person away.
Last edited by racebum; Jun 7, 2008 at 03:04 PM.
Thread Starter
Melting Slicks
Joined: Mar 2008
Posts: 2,453
Likes: 347
From: SC
No offense,but in the civilized world there is a lot more to life than Nascar and racing! Just because you have a sweet car, why drive it around in circles or straight down a track? Just enjoy a nice ride down the highway now and then.
Pro
Joined: Mar 2005
Posts: 666
Likes: 0
From: Walton KY
I agree with RACEBUM to an extent. I have not been to the strip or autocross course with the Sumis on so I cannot comment on their performances. I agree that the Sumis don't grip very well in the cold air. I compensate by dropping pressure in cooler temps. I have never had a problem at the limit. They suck in the snow, but I think that is mostly the car. I don't mind them in the rain which is something I don't drive in very often. I LOVED my BFG KDWS but just kept going thru them like crazy (one set of fronts and 3 sets of rears in 22k miles). The turn in on the Sumis is not quite what the BFGs were but do find the overall ride smoother. For $100, the Sumis cannot be beat.
I looked up specs on TireRack.com. 315 Sumis measure 12.6 section width and 11.6 tread width on 11" rims whereas Goodyear Eagle F1 GS-D3 measure 12.3 section width and 11.2 tread width on 11" rims. With that said, I am not too sure about the pic of the two tires stacked side by side. Could it be that Sumis in the pics are 275s that measure out to 10.9 section and 10.2 tread on 9.5 rims?
I looked up specs on TireRack.com. 315 Sumis measure 12.6 section width and 11.6 tread width on 11" rims whereas Goodyear Eagle F1 GS-D3 measure 12.3 section width and 11.2 tread width on 11" rims. With that said, I am not too sure about the pic of the two tires stacked side by side. Could it be that Sumis in the pics are 275s that measure out to 10.9 section and 10.2 tread on 9.5 rims?
Pro
Joined: Mar 2008
Posts: 702
Likes: 0
LOL i read the part about not racing, it was just hard for me to process. like a foreign language or something...n-o-t ...race. okay, got it i honestly just like seeing people enjoy what they have & if the sumis provide that, all the better. even in a non racing environment i would think that a person would desire the best tire available for your dollar. 315 is a very hard size to buy & i can understand it a bit there since the plain nitto 555 {treadwear 300} is the only other "street" tire being produced. the 555R has a 100 treadwear and extremely small water grooves which i'm sure keeps more than one person away.
i honestly just like seeing people enjoy what they have & if the sumis provide that, all the better. even in a non racing environment i would think that a person would desire the best tire available for your dollar. 315 is a very hard size to buy & i can understand it a bit there since the plain nitto 555 {treadwear 300} is the only other "street" tire being produced. the 555R has a 100 treadwear and extremely small water grooves which i'm sure keeps more than one person away.In all reality, getting a good quality tire is more about safety on the streets than anything. It might give you an extra 10 feet of stopping distance that could keep you out of an accident. also can really help in a quick emergency type move. A good tire may not struggle at all, where a lesser tire might send you spinning. What you mentioned about how the sumis react in colder weather is also a safety issue... some people will never get it. The tire is the only contact between you and the road!
Team Owner
Joined: Dec 2000
Posts: 21,094
Likes: 282
From: Phila., PA burbs
I looked up specs on TireRack.com. 315 Sumis measure 12.6 section width and 11.6 tread width on 11" rims whereas Goodyear Eagle F1 GS-D3 measure 12.3 section width and 11.2 tread width on 11" rims. With that said, I am not too sure about the pic of the two tires stacked side by side. Could it be that Sumis in the pics are 275s that measure out to 10.9 section and 10.2 tread on 9.5 rims?
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Safety Car
Joined: Oct 2007
Posts: 3,816
Likes: 0
From: :45 minutes from everywhere / E-I-E-I-O
I have 4 with 3k on 'em too. I'm glad the 315's out back are NOT the same size as the GY 315 - mine are outside the wheelwell in back by about 1/4 ".
Mine isn't a DD, so the rears do set a good flat spot after a week of sitting, and it takes a half mile to even up.
I'll get over it.
Mine isn't a DD, so the rears do set a good flat spot after a week of sitting, and it takes a half mile to even up.
I'll get over it.
Le Mans Master
Joined: Oct 2003
Posts: 7,625
Likes: 4
From: Director of Bands
St. Jude Donor '08
My biggest gripe with the Sumitomo tires is that (after two different sets) I cannot get them to road force balance and there is an annoying vibration between 65-75mph. We don't even take the car on the expressway anymore because of the vibration.
BTW I got the wheels (ZR1 chromies 9/11) and tires as a package deal from a forum vendor and have had nothing but problems with them...
BTW I got the wheels (ZR1 chromies 9/11) and tires as a package deal from a forum vendor and have had nothing but problems with them...
Le Mans Master
Joined: Mar 2004
Posts: 8,700
Likes: 298
From: Ft. Lauderdale Fl
Team Owner
Joined: Sep 2001
Posts: 62,153
Likes: 1,731
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
I am running them now, they are fine for a driver. So far I think theyre about equal to the Kumhos I had on before.
However, I have not pushed them in autox yet, and dont know if they get slippery as they age like the Kumhos did.
However, I have not pushed them in autox yet, and dont know if they get slippery as they age like the Kumhos did.
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
Ive pushed them fairly hard in the canyons and am happy with them. For some reason they give a little "warning" before the car will go away which I like in a Vette (to avoid the dreaded "snap")...
For the money, whaddya want?
Personally dont drive it much so they will probably get "hard" before they wear out. That and if I do light em up I dont wanna feel bad about wearing out a $300 tire. If I do, no biggie just get some more.
For the money, whaddya want?
Personally dont drive it much so they will probably get "hard" before they wear out. That and if I do light em up I dont wanna feel bad about wearing out a $300 tire. If I do, no biggie just get some more.
Drifting
Joined: Apr 2007
Posts: 1,339
Likes: 2
From: port charlotte fl
My biggest gripe with the Sumitomo tires is that (after two different sets) I cannot get them to road force balance and there is an annoying vibration between 65-75mph. We don't even take the car on the expressway anymore because of the vibration.
BTW I got the wheels (ZR1 chromies 9/11) and tires as a package deal from a forum vendor and have had nothing but problems with them...
BTW I got the wheels (ZR1 chromies 9/11) and tires as a package deal from a forum vendor and have had nothing but problems with them...
I much prefer my Sumi's to the Falkens I had before.
