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Anybody find a source for decent 13 inch tires?

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Old 04-11-17, 06:03 AM
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It felt to me like 205/60s had less grip than 185/70s did because the 6" rim wasn't properly supporting them. In a way this made the chassis (an SA with stock springs/shocks/swaybars) feel a lot more balanced, nimble, and chuckable, since the tires weren't able to make the suspension do things it wasn't able to do.

I had another set of 205/60s - RE71R super sticky tires on 13x7 wheels. Those highlighted the chassis' shortcomings! The car understeered massively because of two things, having only 100hp meant full throttle was corner maintenance throttle and accelerating in a corner = understeer, and the front suspension wasn't stiff enough to keep off of the bumpstops. (Sounds backwards, doesn't it?)
Old 04-11-17, 07:53 AM
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Ah! I can see why you had squirrelly handling with the rear tires being at a higher pressure than the
fronts. That would make the front definitely feel squishy compared to the rear and it would make the
rears more skittish. I generally run lower pressure in the rear to keep it sticking better. For example,
33 fronts and 31 rears. Seems to handle great at those pressures with my tires. Its an old autox trick to
maximize rear wheel traction.
Old 04-11-17, 07:56 AM
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Originally Posted by peejay
It felt to me like 205/60s had less grip than 185/70s did because the 6" rim wasn't properly supporting them. In a way this made the chassis (an SA with stock springs/shocks/swaybars) feel a lot more balanced, nimble, and chuckable, since the tires weren't able to make the suspension do things it wasn't able to do.

I had another set of 205/60s - RE71R super sticky tires on 13x7 wheels. Those highlighted the chassis' shortcomings! The car understeered massively because of two things, having only 100hp meant full throttle was corner maintenance throttle and accelerating in a corner = understeer, and the front suspension wasn't stiff enough to keep off of the bumpstops. (Sounds backwards, doesn't it?)
I had those same RE71 on my waffles and they were awesome tires. I wish they still made
them for 13" and I wouldn't have to run 15" wheels to get good street rubber.
Old 04-11-17, 12:49 PM
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Originally Posted by t_g_farrell
I had those same RE71 on my waffles and they were awesome tires. I wish they still made
them for 13" and I wouldn't have to run 15" wheels to get good street rubber.
This was 1998 or thereabouts... a different species of RE71R than available today! Treadwear 50 R-compounds.
Old 04-11-17, 01:04 PM
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Originally Posted by t_g_farrell
Ah! I can see why you had squirrelly handling with the rear tires being at a higher pressure than the
fronts. That would make the front definitely feel squishy compared to the rear and it would make the
rears more skittish. I generally run lower pressure in the rear to keep it sticking better. For example,
33 fronts and 31 rears. Seems to handle great at those pressures with my tires. Its an old autox trick to
maximize rear wheel traction.
The whole thing seemed counter-intuitive to me. The tires felt loose and sloppy, so I imagined lowering the pressure would make things worse, but it actually improved things drastically. I wasn't expecting it to remove all the steering play too though!

I took the tire pressure down in the front originally to see if it improved anything, assuming I wouldn't be able to tell the difference with the pressure stagger, but I sure did. Would have made sense if I was driving a Corvair . The car has not been this enjoyable to drive since last year when I was considering selling it, so I'm definitely going to try and not touch anything for awhile. I'm just hoping this isn't a false-positive and it gets nasty again, we'll see.
Old 04-12-17, 10:07 AM
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Originally Posted by peejay
This was 1998 or thereabouts... a different species of RE71R than available today! Treadwear 50 R-compounds.

Mine were from the early 90s and there wasn't an R rating yet I don't think. They had a real
low treadwear rating, had to be 200 or below by todays standards. They were excellent
tires. Even after sitting for years. My new Dunlop Direzza *II are about the same level but
of course on 15" rims.
Old 05-24-17, 01:19 PM
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Okay,

So my Federal 595's got to the point where I couldn't really even drive on them. It felt like I was driving on 4 flats. It was awful.

I decided to get the Kumho Solus TA11 in the stock size. Driving impressions:

The steering is a ton lighter and a bit more precise. You can feel the tall sidewall on the tires, and turn in is still a bit vague. In terms of roadholding, there's definitely less available grip, but honestly I hardly think it matters. The amount of grip probably far exceeds what you can actually use on the road, and furthermore I find the slight loss of traction or gradual slip of the tires much more entertaining. While the corning attitude of the car could barely be touched with the throttle on the 205's, I find it much more throttle steerable, more so than my Civic now, which I was using as a reference point before. Wet traction is good, and much better than the Michelin's on my Civic (you can get the tail out on the Civic almost at will, RX-7 feels glued down). Steering feel is the best it's ever been on this car, cornering feels unreal and better than any other car I've driven, mid-corner adjustability is great - more throttle and it goes wide, less and it tightens the line.

The car almost has a split personality though, in corners it feels fantastic. However, going in a straight line the car feels totally inept and out of it's element. While wander is less than the 205's the steering is still horribly imprecise and vague on-center. There's maybe max 1/4" of play at the steering wheel (realistically more like 1/8" maybe). I'd say it's about 50/50 when going straight whether you feel like the steering wheel is connected to the wheels or not. Loads of confidence corning, and almost none in a straight line. What I don't get is that a lot of GT cars (even modern BMW's) have steering boxes which were all about straight lines, surely it can't be that bad.

Overall I'm much happier though.
Old 05-24-17, 03:18 PM
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How many miles on those Federals before they started feeling sloppy? How much tread was left?
Old 05-24-17, 09:18 PM
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Originally Posted by t_g_farrell
How many miles on those Federals before they started feeling sloppy? How much tread was left?
They lasted about 6,300 miles. They started getting iffy around Winter of last year, so I kind of stopped driving the car for awhile because I couldn't figure out what the problem was.

I don't remember what the tread was at, other than there was still a fair amount, they weren't bald or anything. I remember the grip and handling being very good when I first got the tires, but they didn't seem to last long I suppose.
Old 05-25-17, 10:43 AM
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A few things.

First off, the Federal 595 is a 240 treadwear tire. 6,300 miles isn't bad, but then again it isn't great.

Second, you mentioned you stopped driving it around winter time. Summer performance tires are not designed for grip in cold temperatures. If the temps go below 50 degrees, grip will fall off dramatically since they are designed to provide grip at hot track temps, not cold cruising temps.

Third, you really should have looked at the tread wear on the tires before tossing them. If you still have them it's not too late. Check the inside and outside wear to make sure you were running proper air pressures and you didn't have an alignment issue.

Finally, I'm glad you are now enjoying the Kuhmos but I think anyone who plans on aggressive driving, be it autocross, track, or canyon runs won't be satisfied with a tire that handles with your definition of throttle steer. You've got things backwards. What you are describing is understeer, and throttle steering in a RWD car should do the opposite, induce oversteer. Using a FWD car as a reference point doesn't help. If the car goes wide when you get on the throttle, the front end doesn't have enough grip. If the car rotates into the turn, that is throttle steer, meaning you can use less steering input and more right foot to turn the car, hence the name throttle steer.

For solely street driving, I'm sure the Kuhmos are a decent choice. My only worry for me personally, which is why I removed the all seasons from my car, is emergency braking performance. Being surrounded by cars with wider tires and ABS brakes, and driver's who aren't paying attention, I'd rather be equipped with more grip to handle those situations. It was far to easy for me to lock up the rear tires with skinny all seasons.
Old 05-25-17, 11:16 AM
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For the 205/60-13 Federal 595 it is really like peejay says, too wide a tire for the stock 5.5" wide wheels.

The spec wheel for these Legends tires is 13x7 and my experience with 15, 16. 17, and 18" Federal 595-RSR is that that the tire would feel even better on a 13x8.

But if you are getting new wheels, might as well get 15x8s.

Federal does make a 595 in 185/60-13, but it isn't the same performance compound at 460 treadwear.

Then again, like peejay says the stock suspension is not set-up to work with a sticky tire anyways so 185/60-13 595 might be fine.
Old 05-25-17, 06:01 PM
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185/60R13 probably is the better option, but they'll look small if your car isn't lowered and your speedo will be off a bit, but the trade off is slightly shorter final drive for better acceleration.
Old 05-26-17, 07:11 AM
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Originally Posted by hcaulfield57
They lasted about 6,300 miles. They started getting iffy around Winter of last year, so I kind of stopped driving the car for awhile because I couldn't figure out what the problem was.

I don't remember what the tread was at, other than there was still a fair amount, they weren't bald or anything. I remember the grip and handling being very good when I first got the tires, but they didn't seem to last long I suppose.
You drive it in the winter in CO? Shame on you!

Seriously, Chuyler1 makes some very good points. If you insist on driving in the winter
you should switch to all seasons or swap tires fall and spring.
Old 05-26-17, 05:08 PM
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Originally Posted by chuyler1
A few things.

First off, the Federal 595 is a 240 treadwear tire. 6,300 miles isn't bad, but then again it isn't great.

Second, you mentioned you stopped driving it around winter time. Summer performance tires are not designed for grip in cold temperatures. If the temps go below 50 degrees, grip will fall off dramatically since they are designed to provide grip at hot track temps, not cold cruising temps.

Third, you really should have looked at the tread wear on the tires before tossing them. If you still have them it's not too late. Check the inside and outside wear to make sure you were running proper air pressures and you didn't have an alignment issue.

Finally, I'm glad you are now enjoying the Kuhmos but I think anyone who plans on aggressive driving, be it autocross, track, or canyon runs won't be satisfied with a tire that handles with your definition of throttle steer. You've got things backwards. What you are describing is understeer, and throttle steering in a RWD car should do the opposite, induce oversteer. Using a FWD car as a reference point doesn't help. If the car goes wide when you get on the throttle, the front end doesn't have enough grip. If the car rotates into the turn, that is throttle steer, meaning you can use less steering input and more right foot to turn the car, hence the name throttle steer.

For solely street driving, I'm sure the Kuhmos are a decent choice. My only worry for me personally, which is why I removed the all seasons from my car, is emergency braking performance. Being surrounded by cars with wider tires and ABS brakes, and driver's who aren't paying attention, I'd rather be equipped with more grip to handle those situations. It was far to easy for me to lock up the rear tires with skinny all seasons.
Oh, I'm not writing the Federal's off as a bad tire, a lot of people have had good experiences with them it seems. But they did get the point where I wasn't even driving the car they were so miserable to drive on. I drove them in cold temperatures (low 30's) and a few times when the roads iced over (not snow) which couldn't have been good for them. Interestingly enough I had no problems on those days, people in SUVs were sliding all over the place though.

I've always seen people refer to throttle steer as any adjustment in corning attitude based on throttle position - but I could be totally wrong. The car does seem to oversteer with throttle in 1st gear, but it's very mild. These are very mild slip angles anyways, just enough to be noticeable I guess. The point I was trying to make is that the car feels much more responsive that before. I've done a few canyon runs on the tires so far, and I'm quite happy with them. My only real complaint is the large sidewall is noticeable and quick transitions sometimes feel sloppy. These are quite clearly not a performance tire by any stretch of the imagination, but I probably don't push the car the way many people do. I take back what I said about straight-line stability though, the car is fine unless it's windy outside.

I don't feel any difference in braking with the new tires, but I haven't had to do any sort of emergency stops. The rear drums almost always lock up first in my experience. I hear what you're saying about braking though, the majority of drivers here are not paying attention. Most people don't even see my car since it's way below eye level.

Originally Posted by t_g_farrell
You drive it in the winter in CO? Shame on you!

Seriously, Chuyler1 makes some very good points. If you insist on driving in the winter
you should switch to all seasons or swap tires fall and spring.
I don't drive the car in the snow. The roads in the Winter in Colorado either have snow on them or they don't. It's usually only a few weeks out of the year with snow on the ground. So if the roads are clear, the car usually comes out of the garage. If I decide to keep my car long term (it's really a beautiful car and drives well, but I dunno I'm fickle kinda want a Miata or X1/9), I'll probably buy a second set of wheels for Summer driving. I like the stock 13" wheels, but there just aren't a lot of good options for them.
Old 06-12-17, 11:02 AM
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New 185-70R13 Options

I recently noticed my DD tires are 11 years old, so I've been looking at replacements. I was curious, so I checked out 185-70r13 tires I could get locally, and found a couple labelled "performance".
​​​​Hercules Raptis TR1
460 A A, T speed rating, listed as High Performance All Season
Hercules is made by Cooper Tires in Findlay, OH (according to Wikipedia)

Petlas Elegant PT311
No wear ratings, T speed rating, listed as High Performance Summer Tires
Petlas is a Turkish tire manufacturer that have recently broken into passenger tires from tractor tires.
Anybody ever had any experience with these? Any opinions, educated or otherwise?
Old 06-12-17, 10:45 PM
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Does anyone have some thoughts on tire pressure with stock size tires? I got the tires from Discount Tire and they were at 33 psi, and I drove around like that for awhile, but it started feeling skittish. I lowered to 30 psi and that felt a lot better. It says 27 psi on the door, but that seems a little low.

I ask because tire design has probably changed a bunch in 30+ years, and the trend seems to be for higher tire pressures now, but that may just be market expectations. People also like 20" wheels on "sports cars"
Old 06-12-17, 11:39 PM
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I stick with the pressure on the door, or slightly above for regular driving, usually around 32-34 for racing. I'd say the main reason for higher pressures in new cars is the combination of lower profile tires and higher weight. If you aren't pushing the limits of traction and causing the tire to scrub on the sidewall, I think the stock pressure is fine.
Old 06-15-17, 08:39 AM
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Originally Posted by hcaulfield57
I don't feel any difference in braking with the new tires, but I haven't had to do any sort of emergency stops. The rear drums almost always lock up first in my experience. I hear what you're saying about braking though, the majority of drivers here are not paying attention. Most people don't even see my car since it's way below eye level.
As an aside, if the drums are locking up then they aren't adjusted correctly and the brake
bias doo-hicky up by the master cylinder may be stuck as well. I think your car has
auto-adjusters but don't rely on them. I would manually adjust them every 5K miles or
so. Sometimes the drums just need a good overhaul with new hardware and brake grease
to make them work well.
Old 07-21-17, 08:37 PM
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Possible source for 13" tires

Toyo Proxes R888
225/45/13
$132.00 a piece
They are for racetrack/autocross but I'd run em on street. Now if I could just find a good set of old school deep dish rims...13x7? Or 8? Maybe
Old 07-24-17, 07:49 PM
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Well, steering and handling feel like crap again. No idea why. Just two weeks ago I literally had the best drive in the mountains I've ever had in the car, and now it feels like a slop-fest again.

Changing the tire pressure (up or down) seems to help temporarily, but other than that there's really nothing I can do. It feels better in the morning and when it's colder outside, but beyond that it's really nasty. Maybe my problem was something other than the Federals I was running.
Old 07-24-17, 10:40 PM
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Check for an exhaust leak that is heating up a bushing Front or Rear or the steering box.

This is actually more common than you would think. Also common cause of overheating transmission.
Old 07-25-17, 11:31 AM
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Thanks for the response. While slightly off-topic, I brought it up, because the Federal's I was having problems with may have not actually been the problem. The wear is definitely different on the outside edges of the front tires versus the rear tires, I'll have to rotate to see if that cures the problem.
Old 09-12-17, 12:09 AM
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I finally came to the conclusion that if I'm keeping the car, I've got to upgrade to 15" wheels. There's just no choices in 13" tires. Just got some Dunlop Star Specs on my Civic, and wow what a difference.

Meanwhile, I've got Illumina's, RB front swaybar and Spec-RX7 springs on my RX-7 and it feels like it's on marshmallows. The suspension is just not matched to the tires, might be okay on stock suspension, but not working like this. On vintage cars I really like the look of wide 13" wheels, but it seems all the tire manufacturers have abandoned vintage cars, so if I want to enjoy the car, I've got to upgrade. Took me long enough to realize that, we'll see.
Old 09-12-17, 10:22 AM
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Originally Posted by hcaulfield57
I finally came to the conclusion that if I'm keeping the car, I've got to upgrade to 15" wheels. There's just no choices in 13" tires. Just got some Dunlop Star Specs on my Civic, and wow what a difference.
Wise decision. Just look at the sidewall deflection on my 205/50R15 Yokohama S.Drives. Can you imagine a 70 series 13" tire would do with that much grip? These are UHP class while your Star Specs should be a notch stickier since they are EP class. I'm thinking of trying Star Specs next season...it's that or going all in with Toyo R888R.


PS, jump to about half way through the video to see me chase down a Miata. Sure it's a NA and probably a 1.6L, but I'm still a stock port 12a, take 'em when you can. He gave me the point by on the next lap after the video...but we were both working are respective machines pretty hard.

Last edited by chuyler1; 09-12-17 at 10:25 AM.
Old 09-12-17, 12:24 PM
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Originally Posted by chuyler1
Wise decision. Just look at the sidewall deflection on my 205/50R15 Yokohama S.Drives. Can you imagine a 70 series 13" tire would do with that much grip? These are UHP class while your Star Specs should be a notch stickier since they are EP class. I'm thinking of trying Star Specs next season...it's that or going all in with Toyo R888R.

PS, jump to about half way through the video to see me chase down a Miata. Sure it's a NA and probably a 1.6L, but I'm still a stock port 12a, take 'em when you can. He gave me the point by on the next lap after the video...but we were both working are respective machines pretty hard.
Cool video! Yea, you can feel sidewall flex even just driving at the speed limit and changing lanes, it's not too inspiring. Star Specs are pretty cool so far, but haven't driven much on them due to driving my RX-7 right now mostly.


Quick Reply: Anybody find a source for decent 13 inch tires?



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