Road course/auto cross tires on 15" rim

[68 Sport Satellite]

That is some funny ****. VERY true. The 15" street tires are fine for cruising and such but the tread doesn't grip and the sidewalls flex way too much for great cornering.


For the enthusiast that wants real steering response and grip, the sidewalls need to be shorter and the tread needs to be a lot softer.
I run Nitto NT-05s with a 100 treadwear rating. They flat out ......stick!

17-inchers, correct KD?

 

[SlinktRR]

My favorite track day tire (road course) is the Toyo R1R, it is 200 tread wear so can run on the street. The Toyo RR is like the Hoosier r7. Toyo has several 15" options.

 

[Kern Dog]

I am not the authority on the matter but I can attest to what feels right for me.
It looks like 17” diameter wheels are the point where availability of good/great tire sizes are plentiful.
I chose 18s.
I don’t recall exactly why I skipped over the 17” size. I bought mine in2003 so this isn’t really a new trend.

 

[SlinktRR]

Yes 17" is the sweet spot, 15" exists mainly for spec Miata and small momentum cars like it so you will be limited on section width for rear tires on a high horsepower car.

 

[sam dupont]

185 60 13 ?? I think an 89 base model civic had those.

7 1/4 tread works on a 1,300 pound car. I recently bought an excellent carcass, a straight and solid former race car that was always indoors. I might tub it while I can get to everything easily.

One of the most noticeable mods I did was go to Revolution wheels that weigh 9 pounds. A 15x6 Revolution race wheel weighs 16 pounds. A Mopar cop wheel is said to weigh 26 pounds.

If you look at old race wheels, keep in mind outdated metallurgy and age. Be safe

 

[j-c-c-62]

"most noticeable mods I did was go to Revolution wheels that weigh 9 pounds."

From, a Go Kart?

 

[sam dupont]

"most noticeable mods I did was go to Revolution wheels that weigh 9 pounds."

From, a Go Kart?

Kind of... a Lotus Super Seven

I bought them used from Hemmings when we had to go by descriptions over the phone. Had not heard of them so the guy was trying to describe them. To cut the conversation short, I asked: How much do they weigh? He said: On the bathroom scale, wheel and race rubber weigh 13 pounds... I'll take them

 

[weedburner]

I used to build/race Dirt Latemodels, so please forgive me if anyone thinks this is just plain wrong...

I just bought a set of these for one of my cars (15x12 w/ 5"bs), 275/60-15 M/T drag radials...

I also bought a set of wide 5 adapters to adapt them to a 5 on 4.5" pattern. Anybody here try an M/T drag radial on an autocross track?

I also have a '71 Charger, thinking of dropping it in the dirt, radiusing the crap out of the wheelwells, and installing some wide 5 wheels on it as well

Grant

 

[SlinktRR]

Adapters aren't great but you have a lot of backspace so maybe ok for a few autox runs. I wouldn't run them on a road course. Drag radials have a good amount of sidewall flex, and I don't know of any 15" tires that would be optimal for corners that come in a typical muscle car size but if you have them you can run them and see, autox is pretty low risk. 15" road course tires are all Miata sizing, for our cars in 15" you are confined to drag tires or hard as a rock street tires for the era look (bfg radial t/a or cooper cobras). I would get bigger diameter wheels 17-18" and look at something like a Toyo r888r or equivalent sticky autox tire, they offer up to 315/35's. R1R is the most I would drive frequently on the street and I have, maybe 10k miles out of them, R888R is more of a dedicated track tire.

 

[sam dupont]

Used race rubber. 3/4 tread for $100

27.5/11.0/15 Hoosier TDR Vintage – UsedRacingTires

27.5/11.0/15 Hoosier TDR Vintage 3/4 Tread

usedracingtires.com

new: Hoosier Vintage Tire 27.5/11.0-15 HOTD R - 44317HOTDR

 

[Rusty knuckles]

Used race rubber. 3/4 tread for $100

27.5/11.0/15 Hoosier TDR Vintage – UsedRacingTires

27.5/11.0/15 Hoosier TDR Vintage 3/4 Tread

usedracingtires.com

These are exactly what I'm kinda leaning toward. Just curious if anyone else has run them. I'm ok with sidewall flex. The vintage or stock car look is important to me. So absolutely no 17's or 18s even though I know that would make life easier and performance significantly better.

 

[j-c-c-62]

Before you get excited, if used is your goal, understand that listing is only for one tire offered.

 

[33 IMP]

I'm used to driving to the track (dragstrip) and putting on race rubber when I get there, so......
I'd get the cheapest 17" or 18" wheels I could find (with the right backspace) and get the autocross rubber you want, use that at the track, and then throw your tall retro 15" rubber on it for the drive home, and the trips to McDonald's (or wherever).
I believe what you're asking for doesn't exist anymore. Drag tires in 15 by the thousands, tall handling 15" tires...... not so much.

 

[Rusty knuckles]

Before you get excited, if used is your goal, understand that listing is only for one tire offered.

Used tires isn't the goal. But the Hoosier TDR is what I'm curious about.

I'm used to driving to the track (dragstrip) and putting on race rubber when I get there, so......
I'd get the cheapest 17" or 18" wheels I could find (with the right backspace) and get the autocross rubber you want, use that at the track, and then throw your tall retro 15" rubber on it for the drive home, and the trips to McDonald's (or wherever).
I believe what you're asking for doesn't exist anymore. Drag tires in 15 by the thousands, tall handling 15" tires...... not so much.

I'm considering this. And it might be the smartest thing to do. But I is not always smart.

 

[sam dupont]

14 inch perfomance tire (25") $437 ea.

SascoSports Inc is a full-function racecar preparation restoration shop

Same tire in 15": $500 ea. I like Dunlop tires

 

[Rusty knuckles]

14 inch perfomance tire (25") $437 ea.

SascoSports Inc is a full-function racecar preparation restoration shop

Same tire in 15": $500 ea. I like Dunlop tires

View attachment 1624761

Now we're talking!

 

[Rennkafer]

14" Tires, Please. Nobody here is using Miata size tires.
And 265 today is not a very serious a tire size with our cars for track use, however I will admit it might be better than F60's from back in the day.

Miatas also came with 15's, and the serious track rats are running 245s and 275s. Welcome to 2023.

 

[j-c-c-62]

Miatas also came with 15's, and the serious track rats are running 245s and 275s. Welcome to 2023.

A Miata is a great car, and one we all can aspire to handling wise, but your point backfires in the this conversation somewhat being a race Miata might weigh in the 2400lb range, and the most tricked out Miata might be running a 275 tire, us running our unbalanced 3400lb cars comparatively would need to be running say a 390+ series tire to try and be even in the same league for grip, meaning, it is in reality a pointless comparison for reference. A 275 tire is the min for any serious track use for our cars.
Has the OP changed his mind on not wanting a short sidewall tire? I define a short sidewall in this context as anything under 60 aspect.

 

[Rennkafer]

A Miata is a great car, and one we all can aspire to handling wise, but your point backfires in the this conversation somewhat being a race Miata might weigh in the 2400lb range, and the most tricked out Miata might be running a 275 tire, us running our unbalanced 3400lb cars comparatively would need to be running say a 390+ series tire to try and be even in the same league for grip, meaning, it is in reality a pointless comparison for reference. A 275 tire is the min for any serious track use for our cars.
Has the OP changed his mind on not wanting a short sidewall tire? I define a short sidewall in this context as anything under 60 aspect.

I wasn't comparing grip for grip, I was responding to the incorrect information you gave on the availability of 15" tires.

 

[sam dupont]

at autocrosses around here, there is usually a Miata(s) battling for fast time of the day and sometimes get it. bastards are not far from stock either. A guy works hard using factory competition manuals, the internet, and sourcing cool parts to have a fat Lotus Elan clone Miata, spank you.

I wasn't comparing grip for grip, I was responding to the incorrect information you gave on the availability of 15" tires.

I've looked for tall, wide, 15" tires to replicate the tires that came on a special edition Binder.
Until I stumbled onto SascoSports today, I thought my only choices were a Milestar or Goodyear Polyglas GT from Coker. I would like a square edge, like the original H-70's