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Old Nov 9, 2015 | 08:40 AM
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Default Sigma Tires

I'm looking at getting these from my local Les Schwab tire dealer for my 1973 stingray. Does anyone have any insight or opinion on these?

I've looked at getting BFG's again but its a bit of a hassle trying to order them online; these Sigma tires are sold right down the street but there are not many reviews on them.


Amazon.com: Sigma GRAND PRIX PERFORMANCE G/T Performance Radial Tire - 255/60R15 102T: Automotive Amazon.com: Sigma GRAND PRIX PERFORMANCE G/T Performance Radial Tire - 255/60R15 102T: Automotive
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Old Nov 9, 2015 | 08:44 AM
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What company makes them?
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Old Nov 9, 2015 | 08:57 AM
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Looks like they are made by Cooper. Not sure if that helps. Almost all tyre (tire) manufacturers will have budget ranges with different names.
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Old Nov 9, 2015 | 12:30 PM
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The brand is Sigma but I think jotto is right, they are really made by Cooper.

I have stock 15" rims and its getting difficult to find a decent tire anymore in that size. I guess I'll have to bite the bullet and get new rims at some point but for now I'm going to try these and see how they run. I'm going to try 295/50-15 in the rear and 245/60-15 in the front. I really like the stock rally rims, I'll be upset when I have to upgrade!
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Old Nov 9, 2015 | 05:04 PM
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Originally Posted by vetteus
The brand is Sigma but I think jotto is right, they are really made by Cooper.

I have stock 15" rims and its getting difficult to find a decent tire anymore in that size. I guess I'll have to bite the bullet and get new rims at some point but for now I'm going to try these and see how they run. I'm going to try 295/50-15 in the rear and 245/60-15 in the front. I really like the stock rally rims, I'll be upset when I have to upgrade!

Except for summer only Mickey Thompson S/R radials, pretty much all 15" street tires I've seen are just very basic tires which will get you around if you're getting groceries. Any bit of performance driving would make it well worth upgrading to a modern performance tire. Just about the best move I've made with my car and this is one part not worth compromising in my opinion.
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Old Nov 9, 2015 | 05:44 PM
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Originally Posted by Silvertone
Except for summer only Mickey Thompson S/R radials, pretty much all 15" street tires I've seen are just very basic tires which will get you around if you're getting groceries. Any bit of performance driving would make it well worth upgrading to a modern performance tire. Just about the best move I've made with my car and this is one part not worth compromising in my opinion.
Good Advice. I'm contemplating upgrading to newer rims but I'm more of a weekend cruiser type guy and not really into all out performance. At this point still thinking to stick with the old school look for now.

Silvertone, just curious what rim and tire setup you went with.
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Old Nov 9, 2015 | 06:02 PM
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Originally Posted by vetteus
Good Advice. I'm contemplating upgrading to newer rims but I'm more of a weekend cruiser type guy and not really into all out performance. At this point still thinking to stick with the old school look for now.

Silvertone, just curious what rim and tire setup you went with.
Tires: Bridgestone Potenza RE-11, 275/40/18 rear and 245/45/18 front.

Wheels: Coys C5 Chrome, 18x9.5 rears with 5.5" backspace and .25" hubcentric billet spacers. They don't stock the 5" backspace anymore or that would be the best choice. Moved the parking brake cable brackets to the top of the trailing arms just in case.

Same wheels but 18x8 in front with the proper 4" backspace. Fits exactly like stock. A lot of people are OK with the very easy to find 4.5" backspaced rims on the market but to me that makes it look like you got too much fender hanging out over them, and they probably get some inner frame contact.

To share a ton of research, the RE-11 was the best summer street performance tire that comes in the sizes I need. Not cheap! Super stiff sidewalls and the tread pattern will tolerate some water on the road. The Michelin Pilot Sport something or other was as about good but even more expensive. "Ratings" mean I have read hundreds of comments from sponsored track comparisons as well as individual users, many of whom race their cars.

I almost went with 17" wheels but there is less tire selection available and that trend could continue. I could not be happier with my 18s.

Last edited by Silvertone; Nov 9, 2015 at 06:37 PM.
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Old Nov 9, 2015 | 06:35 PM
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Originally Posted by vetteus
The brand is Sigma but I think jotto is right, they are really made by Cooper.

I have stock 15" rims and its getting difficult to find a decent tire anymore in that size. I guess I'll have to bite the bullet and get new rims at some point but for now I'm going to try these and see how they run. I'm going to try 295/50-15 in the rear and 245/60-15 in the front. I really like the stock rally rims, I'll be upset when I have to upgrade!
I'm pretty sure you'll need a 9.5" to 10" wheel width to run a 295 tire. Then depending on your backspacing, it may either stick out of the wheel well or contact the brake cable on the trailing arm(this can be relocated cheaply). I've heard of others using them with fender flares or offset trailing arms. Both ideas seem costly to me. Best to see if your tire dealer can do a test fit before committing to payment.
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Old Nov 9, 2015 | 10:39 PM
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I've got Sygma tires on the front of my car. They've been there for quite a few years now. I needed a 205/70-15 to fit the fender correctly and that was what I found. They've made cross country trips and been over 140 MPH at the dragstrip many times. been 160 or so on some "testing" excursions. The good news is my car gets there quickly and they don't get exposed to the extremes for very long.

They show minimal wear (lots of tread left) and recently I was looking them over in general and there are no signs of funky stuff, cracking, ozone etc.

So for a normal driver car, I wouldn't be scared of them.

JIM


Last edited by 427Hotrod; Nov 9, 2015 at 10:53 PM.
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Old Nov 10, 2015 | 09:00 AM
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Originally Posted by 427Hotrod
I've got Sygma tires on the front of my car. They've been there for quite a few years now. I needed a 205/70-15 to fit the fender correctly and that was what I found. They've made cross country trips and been over 140 MPH at the dragstrip many times. been 160 or so on some "testing" excursions. The good news is my car gets there quickly and they don't get exposed to the extremes for very long.

They show minimal wear (lots of tread left) and recently I was looking them over in general and there are no signs of funky stuff, cracking, ozone etc.

So for a normal driver car, I wouldn't be scared of them.

JIM

Thanks for the feedback Jim and great looking car!!! I'll post pics of my car before and after as well...
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Old Nov 10, 2015 | 09:41 AM
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Originally Posted by Silvertone
Except for summer only Mickey Thompson S/R radials, pretty much all 15" street tires I've seen are just very basic tires which will get you around if you're getting groceries. Any bit of performance driving would make it well worth upgrading to a modern performance tire. Just about the best move I've made with my car and this is one part not worth compromising in my opinion.


I switched my OEM aluminum 15 inch rims about 9 years ago after finally giving up on finding a decent tire in a 255/60/15 (almost all tires for C3's now in 15 inch rims are not very good). I did the switch to 255/45/17 ZR Summer only ultra performance tires for the performance improvement (which was substantial...I would NEVER go back to a S/T rated tire) BUT I was immediately shocked within 100 feet of leaving my driveway about how much BETTER the ride was with these tires versus the former BFG Radial TA. In everyday driving, the car tracks better, steering response is better, and normal handling (not high performance driving) is much improved. The point is that for everyday driving high performance ZR tires make a big difference in the driving characteristics of a C3...even a cruiser, putting aside any performance enhancements these tires bring to the equation. I would switch just for the ride improvement....

Last edited by jb78L-82; Nov 10, 2015 at 09:42 AM.
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Old Nov 10, 2015 | 09:20 PM
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Originally Posted by jb78L-82


I switched my OEM aluminum 15 inch rims about 9 years ago after finally giving up on finding a decent tire in a 255/60/15 (almost all tires for C3's now in 15 inch rims are not very good). I did the switch to 255/45/17 ZR Summer only ultra performance tires for the performance improvement (which was substantial...I would NEVER go back to a S/T rated tire) BUT I was immediately shocked within 100 feet of leaving my driveway about how much BETTER the ride was with these tires versus the former BFG Radial TA. In everyday driving, the car tracks better, steering response is better, and normal handling (not high performance driving) is much improved. The point is that for everyday driving high performance ZR tires make a big difference in the driving characteristics of a C3...even a cruiser, putting aside any performance enhancements these tires bring to the equation. I would switch just for the ride improvement....
I agree that bigger rims will improve the ride substantially and open the door to a wider selection of tires, just can't afford it right now Plus I could see it turning into a "while I'm at it" scenario with getting new rotors, then I'd need new brake calipers since they'll now been seen more, etc, etc lol
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Old Nov 10, 2015 | 10:44 PM
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295/50/15 You may need to relocate the e-brake bracket to the top of the trailing arm . That is last year with 295/50/15 and thay DO not stick out past quarter panel lip.. PM me i have a virtually new set of cooper 295/50/15
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Last edited by diehrd; Nov 10, 2015 at 10:44 PM.
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Old Nov 11, 2015 | 08:48 AM
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Those 295's look bad ***! So it doesn't sound like there are a lot of opinions on the Sigma tires. I guess I'll try them.
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Old Nov 17, 2015 | 03:30 PM
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Originally Posted by vetteus
Those 295's look bad ***! So it doesn't sound like there are a lot of opinions on the Sigma tires. I guess I'll try them.
Name:  sigma.jpg
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Here is a pic of the Sigma tires. So far so good. Hopefully someone else finds this useful.
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