Great Cobra Tires

[RallySnake]

I have been having trouble making up my mind which tires to buy for my Arntz Cobra. The Yokohama Avid S/T's have been on it for too many years and even though there is about 3/32" tread left before the wear bars reach the surface, the rubber has hardened up so much that they had no grip any more.

Thanks to the ClubCobra member who wrote that the Mickey Thompson Sportsman S/T's are softer than the S/R's and are recommended by their tire technicians. I installed 255/60R15's (fronts) and 275/60R15's (rears) yesterday and I am very glad I did.

We ran Santa Monica Sports Car Club's First Friday Night rally this evening and the tires were fantastic. We ran down Balcom Canyon and up Grimes Canyon using Stockton and many other fun roads in the Santa Paula area and just had a blast! These roads have severe altitude and camber changes and are a perfect test of a tire's ability to grip in every dimention. The rounded profile of the Mickey Thompson tire gives it a smooth breakaway which only happens when you push it VERY hard. You get a little noise and then a little "dead" feeling in the steering and then the front tires start to slide gradually. I never got the rears to squeel at all. The speeds I was running through the curves felt like at least one "G" and I got a little motion sick. That hasn't happened since I had Hoosier race tires on the car. The Hoosiers would occasionally try to jerk the steering wheel out of my hands on the freeway, too, but the radial S/T's have none of the bias ply race tire's bad traits. I am really excited about my purchase and feel like I have been on a two hour roller coaster ride.

I bought them at Discount Tire on Parthenia in Northridge, CA for $670.00 mounted and balanced. Best money I have spent in a long time (except for my Apple stock). What really made the evening perfect was receiving the First Place Plaque for the best score in the rally. The evening was so much fun I had to go for another drive to burn up the excitement after I dropped off my Navigator, even though it was after midnight. The loop around Woolsey Canyon to Black Canyon and back on Santa Susanna Pass gave me a chance to push the tires hard through 180 degree downhill loops and hard breaking points. I got home with a really big smile on my face and tired enough to sleep.

Good Night,
RS

[undy]

I love my M/T ET Street Drag Radials. The hook well and last a reasonable amount of time. They bit good enough for me to embarrass a new hi-dollar Ducati to 60 mph the other day They do faily well in the twisties too!

[RallySnake]

Undy,

Have you pushed them hard enough to slide through a curve? How do they handle? Do you have the drag tires on front and rear? I really like the way the tread looks on those but wonder about the soft sidewall and how it works when pushed sideways.

[undy]

I'm running the 315/35/17s M/Ts and they do very well under hard side loading. A set of tall sidewall 15s probably would be a different story. Believe it or not there's not a whole lot of sidewall flex with mine. I run a standard set of front tires, 255/45/17s.

[vatdevil]

I made an autocross run in a cobra with 15 inch SRs, total junk in my opinion. Glad the STs work well for you. There are few good choices in the 15 size anymore so I'm switching to 18 inch and Nittos Nt01 R compound tire....315/30 and 275/35.

[mdross1]

When my car was near finished spent a lot of time trying to decide on what tires to run.Most of the driving was to be street so the car was shode with BFG's.Once the car proved itself to me picked up a set of DOT racing tires.You can bet the car was a whole nother animal.Aside from the sand blasting the wheel wells take when hitting patches of sand these tires would be on the car all the time.

[FatBoy]

Hi,
I've just looked at the Mickey Thompson website and it states that the Sportsman S/T Radials are only rated to 118mph. Do you guys simply ignore that, or not drive that fast?
I currently have Billboards, but I would like to try something that doesn't pull and tug at every imperfection in the road, but I also want retain the Billboard look as much as possible.
Paul

[Silverback51]

Originally Posted by FatBoy

Hi,
I've just looked at the Mickey Thompson website and it states that the Sportsman S/T Radials are only rated to 118mph. Do you guys simply ignore that, or not drive that fast?
I currently have Billboards, but I would like to try something that doesn't pull and tug at every imperfection in the road, but I also want retain the Billboard look as much as possible.
Paul

Avons.

The funny thing is I have had both the BB's and the Avons on my car. Currently has the Avons and I'm going back to either the BB's or the G-7's.

[SPF1061]

Hey John,
I think your's is the first post I have ever read of an Avon user ever going back to something else. Fill me in. Thanks.
Steve

[ERA Chas]

Originally Posted by Silverback51

Avons.

The funny thing is I have had both the BB's and the Avons on my car. Currently has the Avons and I'm going back to either the BB's or the G-7's.

Why dissatisfied with the Avons and switching back to G'Years?

[SPF1061]

Hey John /Silverback,
I think your's is the first post I have ever read of an Avon user ever going back to something else. Fill me in. Thanks.
Steve

[Dwight]

I think the rating of 118 mph is "118 mph for one hour". Most of us don't drive that fast for an hour.

Dwight

[Silverback51]

Originally Posted by Dwight

I think the rating of 118 mph is "118 mph for one hour". Most of us don't drive that fast for an hour.

Dwight

That rating is also at 100% of the rated load capacity. Depending on the tire, some of them could support the entire weight of a Cobra.

[Silverback51]

Originally Posted by ERA Chas

Why dissatisfied with the Avons and switching back to G'Years?

Originally Posted by SPF1061

Hey John /Silverback,
I think your's is the first post I have ever read of an Avon user ever going back to something else. Fill me in. Thanks.
Steve

Avons are great tires, and are without a doubt the best DOT rated 15 inch radial tire available for a Cobra bar none. So I'm not dissatisfied with them.

I have three reasons for going back to the GY's.

First is I prefer the looks.

Second is the feel as you approach the limits. The GY's are a little more forgiving. And don't get me wrong. The Avons are pretty good also, it's just that the GY's are a little better in my opinion.

Third is probably the biggest reason. There is a 45 pound difference in weight between a full set of GY's and Avons. That's a boat load of unsprung mass you can save just by going with the GY's.

The front tires save 12.5 pounds each. 17.0 vs 29.5. And the rears save 10 pounds each. 21.0 vs 31.0.

Since my wife and daughter both refuse to even drive the Cobra, I do not have to worry about them being surprised with the twitchy aspect of the GY's. Me? I'm used to them and it does not bother me.

I suppose I should add that I try to put 4000 to 7000 miles a year on my car, so it's not a garage queen or show car. The tires get used up in about 2 seasons of driving.

Hope that answers your questions.

[ERA Chas]

Originally Posted by Silverback51

Third is probably the biggest reason. There is a 45 pound difference in weight between a full set of GY's and Avons. That's a boat load of unsprung mass you can save just by going with the GY's.

The front tires save 12.5 pounds each. 17.0 vs 29.5. And the rears save 10 pounds each. 21.0 vs 31.0.

Thanks for a comprehensive answer. I agree about the weights. With my mags, the combined tire/wheels weigh 35 front, 42 rear. The wheels are 18 and 21 alone.
Not a factor street Avon users care about but significant on the track for controllability.

[SPF1061]

Originally Posted by Silverback51

Hope that answers your questions.

Yes, and good answers to boot. The weight is especially significant if doing serious tracking. I drive my Cobra, too. 62,000 miles in a bit over 10 years so far. I do a lot of open track events, but I don't want to fool with a separate set of wheels and tires for track use. The Avons just can't be beat for street and track use. They are expensive. I'll be looking at set number four pretty soon.

[RallySnake]

Fatboy,

To answer your question about the 118 mpg rating of the Mickey S/T tires, I am getting older and the "Need for Speed" has diminished. When you get over 60, it's more of a fight with what you can do and what hurts too much. I play tennis at least one a week and work out to stay in shape so that I can drive the Cobra on 12 hour events. However, these events do not require high speeds and can be run at legal speed limits. Driving a Cobra at over 100 requires a lot of focus and is physically draining. So, I keep the speed down and focus on winning events with precise timing. We have a big rally coming up on March 17 from Riverside to Palm Springs. If you really want to have some fun with your car, join us. The rules have been changed to make the course very easy for beginners. See the information here: ITNRALLY.ORG.

RS

[FatBoy]

Rallysnake,

Thank you very much for the invite and I would dearly love to take you up on it. However, as I live in England, I'm unlikely to have the opportunity I'm afraid.

Although I have done a couple of track days where the speeds can get pretty high, my question was less about the reality of high speeds and more about the "suitability" of the tyres for a Cobra as viewed by an insurance company in the unfortunate event of having to make a claim.

Thanks again.

Paul

[RallySnake]

Just a quick update. I have been rebuilding the top end of my engine and rewiring the car since December. It's easy to inspect the tires from under the car. The Mickey S/T tires are wearing very evenly and the rears are about 1/2 tread. I probably have 20K miles on them and did not expect them to last so long.

During the Stardust rally in November, we ran from Palmdale to Las Vegas and spent more than 12 hours in the car. There was one occasion where we pushed the speed a little to get to a checkpoint in time, but mostly it was back road cruising. My Navigator is over 60 and has a heart condition so I take it pretty easy.

After driving all night, I was getting a little tired and wanted to raise the excitement level a little. On one tight negative camber right hand turn in south Las Vegas, I pushed the accelerator a little harder through the curve and was surprised that the rear end slid out. It was easy to catch and I expected that the right rear tire had lost some pressure. I got out to check it at the next checkpoint. The tire was fine and the problem remained a mystery until I got home and slid under the front of the car to pull the oil pan. That's when I saw the right hand sway bar bracket was broken in half and bent wide open. It had scraped over too many parking barriers, I guess.

The point is that these are great tires and I highly recommend them.

[BevanWright]

I used to suffer with Dunlop d40 tyres for road and track, lack of traction and sliding a lot.

Replaced these with Kumho ecsta semi slicks, and what a transformation. Give them a quick wheelie to heat up and they are as good as some slicks I have used. Totally improved acceleration, able to use full power under acceleration now. I used to wheelspin at 100 mph if slight damp.