Can ACR's new Kumho Tires be that fast?

[Bruce]

Dodge is advertising the new Kumho V720 tires are "1.5 seconds faster than off-road only race tires", is this just marketing BS or can this be real? I've driven Hoosier A/R series tires, Kumho V700, V710 and XS (the V720 is suppose to be the XS replacement), and how could the treaded V720 (or improved version of the XS) be "1.5 seconds faster than off-road only race tires" which are even faster than DOT slicks like their own V710 and Hoosier's A7 or R7's??? I would really like to believe them but will have to call it BS. Please someone proof me wrong.

[TrackAire]

I can't wait to find out too....the number one thing that makes the car fast is the tires. Everything else is built from there. If SRT wanted the ultimate track beast, the tires would have to be incredible gumballs. I would not be surprised if these tires were stickier than a Hoosier R7.

It is not just the stickiness of the tread that matters, sidewall stiffness, belt design, etc all will contribute when tenths of seconds are on the line.

The downside of this type of performance is a tire that might wear out in 2500 miles of street driving. Very exciting times ahead.

[sammyv]

Funny, I had just read that and was thinking the same thing! Maybe 1.5 sec. faster than the corsa's?

[FrgMstr]

Loved my Kumho Exsta XS tires back in the day.

[99RT10]

Loved my Kumho Exsta XS tires back in the day.

Still have the XS on my 99, can't wait for the 720's to be available.

[AZTVR]

Dodge is advertising the new Kumho V720 tires are "1.5 seconds faster than off-road only race tires"
I would think that they are referring to one specific model of tire; not, a generic, nebulous reference. They just don't say which tire.

[Bruce]

I would think that they are referring to one specific model of tire; not, a generic, nebulous reference. They just don't say which tire.

They were probably referencing some off-road mud tires for the Jeep Wranglers...:lame:

[VENOM V]

The Trofeo R upped the game. A racer friend tested Nitto NT01s against them and said the Trofeos are faster, so I would not be surprised if the V720s have yet again raised the bar to be the fastest street R compound available.

I'd be shocked if the 720s are faster than Hoosier R7s, but will try both and report lap times 👍

It's gonna be a while, gotta wait for Extreme Aero ordering to open up.

[Darius]

Riding in Chris's white TA after driving mine I didn't feel much of a difference between the stock Pirelli's and my hoosiers. It could have been the fact I was in the passenger seat but the car stuck extremely well.

[XSnake]

The current 720's are a 200 treadwear tire. I'm going to assume that the ACR specific tires will be the same pattern but a different compound.

[TrackAire]

The current 720's are a 200 treadwear tire. I'm going to assume that the ACR specific tires will be the same pattern but a different compound.

That is what I'm thinking too.....hopefully Kumho is smart and makes them very reasonably priced so they can grow some market share for the track day crowd and not just for Viper but Vettes, Mustangs, Camaros, etc. This could give Hoosier a little competition, especially if they are sticky and have a bit of lifespan to them.

[Bill Pemberton]

If it states Off Road Only Race Tires then Trofeos, R7s , Sport Cups, etc. are a moot point , since this would mean they are essentially referring to Slicks.If taken off of an old story , we can assume the writer in stating 1.5 seconds faster than other race tires, could be referencing the DOT brands above ,as most generally call these race tires. If a new story, or Dodge direct reference, and it specifically states Off Road Only Race tires ( slicks ), then this improvement is beyond amazing --- hopefully the tests will appear in the near future, as rumored.

[LA STIG]

I made a call to "Deepthroat" about two months ago when I first heard of the V720. Apparently it is not a carry-forward of the V710 (which is too bad because that was a hell of a tire on my C6 Z06) and I got the impression that it would be more along the lines of the Ecsta XS of which I ran many sets and got good results. But the XS was no V710, either.

I'm really looking forward to the V720 in Viper sizes because I like choices. I've run the Zero's, Corsa's, and R7's over the last six months and I'm still interested in trying something new, especially now that I've got enough negative camber in the front to work with the stickier tires.

I agree with one of the earlier posts that tires are the number one variable and now that I've run out of talent I can assure you that grip is all I've got going for me.

[VENOM V]

Riding in Chris's white TA after driving mine I didn't feel much of a difference between the stock Pirelli's and my hoosiers. It could have been the fact I was in the passenger seat but the car stuck extremely well.

Darius,

Having put many laps on my Corsas and mixing in Hoosiers, I think you'd find the Hoosiers to be night and day grippier than the Corsas. Love the Corsa for its longevity, but the Hoosier is the new drug that Huey Lewis wanted!

So if the V720 is even in the same zip code as a Hoosier, that will be one awesome tire. Drive to the track, open a can of whoop ass, then go to Carmel for a steak dinner and enjoy 17-mile drive. My kind of tire, if it measures up to the hype.

[roadrunner]

The press photos show:
Treadwear 20
Traction AA
Temperature A

For what it's worth! :)

[VENOM V]

The press photos show:
Treadwear 20
Traction AA
Temperature A

For what it's worth! :)

I had heard 20 treadwear too! Hoosier R7s are treadwear 40, LOL. The Corsas are rated at 60, although I got thousands of miles out of them and many track days. I don't put a lot of weight in treadwear numbers.

But you know if they're rating it at 20, it's gonna stick like crazy :icon_devil:

[TrackAire]

Unfortunately there is not set standard when tire companies put a treadwear rating on the side of a tire. A 60 rating may have a softer durometer reading than a 40 rating. It depends on the manufacturer....at least that is what I have been taught.

Belt, sidewall and carcass design will have a lot to do with the success of this tire (and the ACR) if they are matched up correctly to the ACR's camber curve, spring rates, downforce, etc.

Tread compound softness is only a part of the equation. Lateral grip is important, but having a tire that can accelerate hard (with 640 hp that really comes into play) and can harness the energy of the ACR's new brake package, that is where tenths are shaved off your lap time. The Hoosier is a great tire but it is a universal designed not specifically made for the new ACR. I'm hoping that Dodge and Kumho really worked hard together to extract the most out of both the tires and cars capability. Lets just hope they don't come in a $800.00 per tire.

[AZTVR]

The press photos show:
Treadwear 20
Traction AA
Temperature A
Are there photos of the tire, or is that just annotations to the photo? Just wondering because Kumho already has a V720 on the market (not Viper sized) with a treadwear rating of 200. It seems very strange of them to market a specialized version with such different specification but still use the same model number. Perhaps they are keeping the same general construction and tread pattern? It will be interesting to see.

[roadrunner]

11667

http://www.autoblog.com/2015/05/12/2016-dodge-viper-acr-pricing/#image-52

Autoblog has the high resolution pics... zoom in... you can read the numbers for your self. It is a custom tire... even has the ACR logo on it. Appears not to be a stock shelf V720...

[Gonabite]

Unfortunately there is not set standard when tire companies put a treadwear rating on the side of a tire. A 60 rating may have a softer durometer reading than a 40 rating. It depends on the manufacturer....at least that is what I have been taught.

Belt, sidewall and carcass design will have a lot to do with the success of this tire (and the ACR) if they are matched up correctly to the ACR's camber curve, spring rates, downforce, etc.

Tread compound softness is only a part of the equation. Lateral grip is important, but having a tire that can accelerate hard (with 640 hp that really comes into play) and can harness the energy of the ACR's new brake package, that is where tenths are shaved off your lap time. The Hoosier is a great tire but it is a universal designed not specifically made for the new ACR. I'm hoping that Dodge and Kumho really worked hard together to extract the most out of both the tires and cars capability. Lets just hope they don't come in a $800.00 per tire.

You are 100% correct. You can not compare tread wear from one manufacturer to the next. Its a standard exclusive to each manufacturer and their brand, not an automotive standard.

[Eachey51]

Treadwear rating is just a generic number. I autox alot and the rules state i must run at least a 200 treadwear tire. Do they all wear the same or grip the same? Nope

[rw99]

...just wish Kumho would do a charity run of these new tires in "old" sizing for the previous ACR :D

[AZTVR]

http://www.autoblog.com/2015/05/12/2016-dodge-viper-acr-pricing/#image-52

Autoblog has the high resolution pics... zoom in... you can read the numbers for your self. It is a custom tire... even has the ACR logo on it. Appears not to be a stock shelf V720...

Thanks. Definitely does not look like the V720 now on the market. From what I can see of the outer quarter of the tread pattern, that is different also (less grooves, as one would expect for its advertised performance target)

[VENOM V]

It's not new for tire manufacturers to market a different construction tire under the same name. The C6 ZR1's MPSC run-flats were specificially designed for the ZR1 and yield much faster lap times than the MPSCs that came on the Gen IV ACR. This was confirmed by the Viper engineers who tested the tires back to back.

So I'm not expecting that the new ACR's V720 perform similarly to any existing Khumo, likely much better as they put the ACR name on them. Can't wait to see how they do. I'm cautiously optimistic, but knowing that marketing hype can get carried away I will wait to see the tests and lap times. I will still likely track my ACR with Hoosier R7s, unless these V720s pull off a small miracle and actually yield better lap times than the Hoosiers. Other factors will be important too, such as how many sessions they remain fast before heat cycling out and losing grip, how good they are in varying temps, how quickly they heat up on track, how they perform 20 minutes into a session. Hard to beat a Hoosier. Even if they aren't as fast as a Hoosier, if they are close and are a true streetable R-compound, then they've hit a home run.

[Dusty1]

With the newer Hoosier R7's that will be an interesting comparison. We need to get them in the 18" fronts for the rest of us to find out though.

Richard

[Bill Pemberton]

Good call Dusty, I kept wondering about this also, since no provision for all the older cars using an 18 inch front rim will really limit the number of drivers who would even consider switching to this tire.

[V10LEE]

It's not new for tire manufacturers to market a different construction tire under the same name. The C6 ZR1's MPSC run-flats were specificially designed for the ZR1 and yield much faster lap times than the MPSCs that came on the Gen IV ACR. This was confirmed by the Viper engineers who tested the tires back to back.

.

Glad you brought this up. I think this was overlooked by a lot of people . Especially at the time when Randy Pobst ran the TA vs the ZR1, and then when he did the 1:33 record lap in the TA. Nobody knew it was the ZR1 cups that they put on the TA when it was mentioned in their testing of tires..