Folks I have a few tire related questions. First off, the Goodyear F1 run flats don't seem to perform to their price. To me they are too hard and the rear of my C5 seems to be too jumpy because of this. Am I wrong or are we paying more for the run flat capability rather than the adhesion to the road? I am not only looking for more adhesion to the road but a good value if there is one as well. I have heard good things about the Kumho tires yet they seem to be the cheapest of the lot. I can't fathom the cheapest tires being anything but that. The Avon and Sumitomo are relatively cheap as well. I am not looking for the cheapest tire but I am looking at what is the best value for what I want, which is adhesion. Any input would be great.

 

...then check a recent edition of Car & Driver. Although they used "only" a 325 BMW as a test mule, you are very likely to experience similar results with your C5. To minimize variables such as driving techniques, track surface temps, etc, C&D enlisted the help of the Tire Rack and their test mule vehicle. Although the track used was small, it's lined with sprinklers that can soak the asphalt. "It took three days to perform all the tests. We accerated to 50 mph and then braked to a standstill. There was a benefit to that lower speed: It ensured that we were measuring the braking performance of the tires and not just brake fade."

"In addition to factoring the wet and dry scores, we gave points based on a tires's price and tread-wear grade, which is a rough estimate of how long a tire will have usable tread." "Our test focused on measuring performance, so we decided that results in the dry-lateral grip, for example - would carry the most weight."

So, without further adeau, here're the results:

(Best to worst):

NUMBER 1: Goodyear GSD3: "As an all-around performance tire, you can't beat this Goodyear. It was the best performer in all three wet-track tests and was very competent in the dry. It generated .94g on the dry skidpad, only .01g off the first place (dry) BFGoodrich and tied with the Yokohama and Hankook.
The Goodyear gripped so well, that you might not have been certain that the road was wet. It held onto the wet track with .82g of stick, an impressive figure considering the worst tire in that test made only .67g.
...And like the Continental, the Goodyear had a high 280 trad-wear grade. At $145, ieach, it's $34 cheaper than the most expensive (guess which tires have THAT distinction!).

2nd place: Continental ContiSportContact 2: "It simply didn't feel as sporty as the others.....on dry surfaces, the Conti never rose above third from last among 11 tires. It felt soft and imprecise. But in the wet, the spread from best to worse was 15 percent, which made for a larger point spread (giving the Contis a boost). Plus the Continental had a 280tread-wear grade that was the highest (tied) for this test.

3rd place: Yokohama Advan Neova AD07: Excellent dry performance, but a bit on the slippery end in the wet stuff - expensive at $175 apiece.

4th place: Michelin Pilot Sport PS2: "At $179, the PS2 is the most expensive tire in the test." Competent, but expensive sums up this tire.

5th place: Hankook Ventus R-S2 Z212: At $99 each, these are the least expensive tires - very good on dry pavement, but "greasy and slow to recover" on the wet stuff.

6th place: Dunlop SP Sport Max: "In the dry, the tire seemed to lose its confidence..."

7th place: Pirelli P Zero Rosso Asimmetrico:"In the dry-lateral-grip test, the Pirelli tied for second to last, and it finished seventh in the dry-braking test.

8th place: Toyo Proxes T1R: "...the Proxes never placed higher than eighth in any test"...nuff said!

9th place: Bridgestone Potenza RE050A: "it felt dull and disconnected and was somewhat soft and imprecise when driven hard."

10th place: BFGoodrich g-Force T/A KD: Outstanding performance on dry surfaces, but very scary on wet surfaces - don't get caught in a rainstorm wearing these shoes...

11th place: Kumho Ecsta MX: "They didn't offer much grip and the time of 30.28 seconds in the dry autocross was .62 second slower than the fastest tire. That may not seem like much, but our course was only 0.3 mille long, and on a longer track, that gap would be commensurately greater." "And although the MX - at $136 per - was the third-least-expensive tire in our test, the high score in the price category wasn't enough to regain ground lost in the performance tests."

On a congratulatory note, the first place tire is made right here in the USA by an American tire company


....boy, here's three cheers for the Ctrl-C and Ctrl-V keys....

BTW, I agree with you about the somewhat dangerous side-hopping we had with runflats. They are heavier (by 6 lbs each), require special equipment to dismount and mount, cost more, and wear faster than most non-runflats.

 

I'm very pleaes with my Michlen run flats.

 

I just got rid of my run-craps..... I had heard all the hype about how much better your ride was & how much quieter was..... well that's not hype.... its true.... I did a lot of research and decided on BFG - KDW IIs.. I love them.... awesome look.... great dry traction, I don't know about the wet, mine is not a daily driver. Got the set mounted and balanced for less than a grand! I'm happy with them.

 

I have GoodYear GS-D3's.... a great tire

 

I've always had the runflats by goodyear so I can't compare to for instance GSD3's but I'm sure they do ride nicer. Guess I just have never thought the runflats ride bad as most of my vette driving is highway.

I hang with the goodyears primarily because the stiff sidewall has saved damage to my $ BBS wheels more than once when I've encountered some vicious potholes here in beautiful Ohio. Maybe a little weird but that stiff sidewall is something I view as a benefit to reducing any damage to the wheels..........

 

All runflats have stiff sidewalls. I had the Firestone Firehawks and noticed they have a lip that sticks out slightly past the edge of the wheel to protect it against damage. They're also quieter than the Goodyears.The runflats will always be more money. But that's the price you pay for peace of mind against flat tires. I have runflats for cruises and am getting a second set of wheels for in-town driving with non-runflats for more traction.
BTW, the Firestones were a little cheaper last time I checked. The tread width is also a little narrower if I remember correctly. But they still stick better than the Goodyears.

 

I agree with Dave68, the Goodyear F1 GS-D3 tire is a real sleeper. In fact, Goodyear is in the process of bringing out a 295/35ZR18 GS-D3. It should be available in April. That means that C5 Z06 owners can also switch over to the GS-D3 when their original tires wear out.

.

 

You know - all this admiration for the GY GS-D3 is swell, but the offerings in aftermarket sizes is a major limiting factor in my mind. I wanted a tire made in the USA too. In "plus" sizes the offerings become very limited.

Lots of folks like the Nitto 555 - seems like a nice tire and it's pricing is favorable, but if you start to stray away from OEM sizing, limited or no availability.

The other question in my mind - is many folks here complain about the GY OEM EMT's, but if you understood that tire's capability you'd understand why it exhibits the characteristics that it does. The C5 has tires that can be driven up to 200 miles with no air pressure at speeds up 55 mph. There is no other tire with that capability. There are other run flats made by Michelin, etc. but they cannot be driven on for that distance. In order for the GY - EMT to perform to those parameter, the sidewalls have to be very stiff so that the tire does not roll off the rim. But the stiff sidewall transmits road noise and vibrations that a softer sidewall will absorb. Also - because of it's stiffness it has a reputation for being a poor handling tire, it doesn't flex at all.

As long as we are going to refer to articles - take a look at this one....

http://corvetteactioncenter.com/kb/q....php?qstId=515

For some - the run flats are the only answer. For others they are not. If my wife was driving the car as a daily driver - I'd want runflats on the car in case she got a blow out or flat. For me - I want more rubber and better ride/handling characteristics. I chose a different tire in "plus sizes".

Bottom line - there is no right or wrong answer to "Which tire?" It depends what you're looking for.....

BTW - I have the #4 tire in the highly acclaimed and C & D article, I guess I spent too much.......

 

I just purchased the Falken's for my ride and added the Bilsteins Spot Shocks! My car is still at the tuner getting th H/C, 3:42 and 3200 T/C so I will not know how it feels yet. THe tires were ordered yesterday and should be here by wedsday! I will keep you posted, but I hope to get more traction and eliminate the road noise and wheel hop!

 

Kumhos here, i would be anything else unless fuzion comes out with the proper tire sizes for what i want.