Cooper STT vs Toyo Open Country 315's
- Thread starter Romer
- Start date
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MaddBaggins
Remember the KnightRider!
hme hmmm hmmm hmmm, dodoooo doododo, hummmhummm
Come on Alvin, we don't have all day
I was using the word run loosely
I don't know what that means.
This is why:
http://www.toyojapan.com/tires/pdf/TTT_05.pdf#search=" tire molds"
I have never heard of a mold with that many joints???
MaddBaggins
Remember the KnightRider!
I don't know what that means.
No seam down the middle. Having done my fair share of fiberglass molds for concrete way back when, I would say the mold for these has 2 sides and 10 pieces for the rolling surface of the tire.
MaddBaggins
Remember the KnightRider!
After looking at your link, yup Coopers are segmented 12 pieces
The only segmented mold process I have heard of used by Michelin, Goodyear, Pirreli, Bridgestone, etc. has two side plates and center segments around the circumference. The only clamshell mold process I have heard of uses two halfs. That's why I am scratching my head. I need one of those smilies that scratches their heads...
I know that Cooper was taking alot of heat few years back because of defects and I did see in my research that they were at least using the segmented process on some of their tires. I just can find specifically which ones...
Ken, Iverness has the 315 Toyo's on his truck with the OME 850/863 spring combo (+ spacers up front). I believe the wheels are the same backspacing as stock. You can see several pics of his truck wheeling with those tires here. The single best comment, that I think he would share, that I can make about them is their "on road" manners compared with comparable trail tires. They are the most quiet tire with this much tread void I've experienced. I believe the Toyo's may allow you to run a higher tire pressure on the road? My only complaint is exactly what's been pointed out already - the bigger sizes are too wide. The Toyo Open Country A/T's I got for the road are 355/70R17 and if you can believe it, they seem to run a little wider than that spec.
smittycrusher
"Hey big guy, you a golfer" - Roger Dorn
I think I am going to go with cooper b/c of the knights on the sidewall. End of arguement.
j/k.. i love this thread as these are the two I am narrowed down to also. As it stands Cooper will get the nod for me...price is important to me. Any weight I can save is nice also. I have not really heard any negative opinions on either...which is what makes it so tough. I do like that they are both siped. Anyone ever had either in snow (deep, medium, shallow), slush, or mud? What did you think?
j/k.. i love this thread as these are the two I am narrowed down to also. As it stands Cooper will get the nod for me...price is important to me. Any weight I can save is nice also. I have not really heard any negative opinions on either...which is what makes it so tough. I do like that they are both siped. Anyone ever had either in snow (deep, medium, shallow), slush, or mud? What did you think?
- Thread starter
- #29
Thanks Mike. I'm still not sure if the the 3" additional width of the Toyo is a good thing or bad thing. It would be closer to the flares. Where is MOJ when you need him.
- Thread starter
- #31
I doubt the coopers would rub. My 285 BFG AT KOs have no issues and there is plenty of clearance for the additional height. It's the width I was thinking about. Now you guys got me thinking about Toyo's.
But I am just comparing the specs in the first post. I think the tread pattern is similar so the specs for weight, width and height are the differences. Height isn't a big enough delta to matter. The additional weight bothers me and I am concerned that the extra 3 inches would rub the flares at certain points. These were the points I wanted to discuss.
But I am just comparing the specs in the first post. I think the tread pattern is similar so the specs for weight, width and height are the differences. Height isn't a big enough delta to matter. The additional weight bothers me and I am concerned that the extra 3 inches would rub the flares at certain points. These were the points I wanted to discuss.
I just measured my 315 Toyos. 10" tread and 12.5" section (317mm), best I can measure.
I don't know where this 3" additional width of the Toyo is coming from? Ain't happening, bro
3 inches is 75MM. These would be 390's!!These tires are very quiet. Essentially the same as my 1/3 worn BFG AT KO that Citadel just bought. They track and turn every bit as well as the smaller tire.
I can tell the difference between the 295 BFG and the 315 Toyo from a power standpoint, but I don't think that will surprise anyone.
I only have 150 miles on the tires, so my views must be taken with that in mind (except for the tread measurements....they are as accurate as a half-blind man can make them).
Oh, I should mention. They are one sweet looking tire
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Ahhh, Google. Interesting article on rotating mass:
http://forums.evolutionm.net/showthread.php?t=225495
Unsprung Weight - Part 2
By: Eric Albert
Introduction
In the first part of this series, we took a look at the effects of high unsprung weight on suspension and handeling. In this part, we will look at rotating mass. Be careful not to confuse unsprung mass with rotating mass. Reducing both is good, but they are not the same. Let's take a look.
Rotational Inertia (or Momentum)
Rotational inertia is a concept a bit more difficult to deal with than unsprung weight. Inertia can be thought of as why a car wants to keep rolling once moving, or remain in place once stopped (unless you forget to set the parking brake on that hill). I believe the terms momentum and inertia are interchangeable. The term “flywheel effect” also refers to these concepts. In a car, there are a number of rotating masses which require energy to accelerate. Up front, ignoring the internal engine components like the crankshaft, we have to worry about the flywheel, clutch assembly, gears, axles, brake rotors and wheel/tire. Out back its a little simpler (for FWD) with just the brakes and wheel/tire contributing most of the mass.
The more mass an object has, the more energy it takes to accelerate it. To accelerate a rolling object such as a wheel, you must both accelerate its mass plus overcome its rotational inertia. As for braking, you must overcome its rotational inertia plus decelerate its mass. By reducing the weight of the vehicle's rotational mass, lightweight wheels provide more responsive acceleration and braking.
Before continuing with our informal analysis here, I want to point out something very important about rotational inertia. We’ve all seen the ice skating move where the skater starts spinning. She pulls her arms in and speeds up, then extends them again and slows down. Why is this? Well, the further a mass is from the center of rotation, the faster it must travel for a given angular speed (how many degrees of an arc it traverses per time unit). The faster anything moves, the more energy it has, so when the arms are pulled in, conservation of energy says that the rotation rate must increase due to equal energy being applied to the same mass over a smaller diameter. Applying this to wheels and tires, which have most of their mass spread as far as possible from the rotation center, I think you’ll agree that it naturally takes more energy to accelerate them. Example: Take a two identical masses, but one is a solid disk of diameter D, the other is a ring of diameter 2D. The ring will require more force to accelerate it (in a rotational manner). Therefore a heavier rim with a smaller diameter could have less rotational mass than a lighter rim of a larger size, and accelerate faster with the same force applied.
The effect of rotating mass can be calculated using Moment of Inertia (MOI). MoI is related to not only the mass of the rotating object, but the distribution of that mass around the rotational center. The further from the center, the higher the MoI. The higher the MoI, the more torque required to accelerate the object. The higher the acceleration, the higher the torque required.
Because of this, the weight of rotating mass such as wheels and tires on a car have a bigger effect on acceleration than static weight such as on the chassis on a car. When purchasing new wheels and tires for a performance car, it can be useful to compare the effects of different wheel and tire combinations. This is especially true when considering upgrading to larger wheels or tires on a car.
The use of light-weight alloys in wheels reduces rotational mass. This means that less energy will be required to accelerate the wheel. Given that each pound of rotational mass lost provides an equivalent performance gain as a 10 pound reduction in vehicle weight, the benefits of light alloy wheels on vehicle performance cannot be overlooked.
For example:
***A reduction in the weight of the rim/tire assembly of 5lbs x 4 (all around the car) is equivalent to a 200lb weight reduction in vehicle weight (thats worth 0.200 in the 1/4 mile)***
So What's the Point?
The point of this discussion is as follows: There is a great deal of rotational mass to deal with in a car and tires and wheels may only make up half of it. Estimates for weight (o.k. for comparison since they’re all in the same gravity field, therefore the mass would be a similar ratio)
Front: Rear:
Wheel/tire: 30-35 lbs each 30-35 lbs each
Flywheel: 15-20 lbs
Clutch: 15 lbs
Halfshafts: 7-10 lbs each
Gears: 5-7 lbs
Rotors: 3-5 lbs 3-5 lbs
Misc: 3-5 lbs 3-5 lbs
------------------------------------------------------------------
Total: 115-148 lbs 76-90 lbs
So a couple pounds here and there on wheels and tires will make a difference, but that difference is magnified because that weight is placed further from the axis of rotation than any other mentioned (remember the ice skater). All these masses must be accelerated, so any reduction is a good thing. Now you know why we always say don't get those 18" rims for your civic. Not only are the heavier, they have a larger overall diameter. Even with lower profile tires, most plus sizing leaves us with a slightly larger wheel.
http://forums.evolutionm.net/showthread.php?t=225495
Unsprung Weight - Part 2
By: Eric Albert
Introduction
In the first part of this series, we took a look at the effects of high unsprung weight on suspension and handeling. In this part, we will look at rotating mass. Be careful not to confuse unsprung mass with rotating mass. Reducing both is good, but they are not the same. Let's take a look.
Rotational Inertia (or Momentum)
Rotational inertia is a concept a bit more difficult to deal with than unsprung weight. Inertia can be thought of as why a car wants to keep rolling once moving, or remain in place once stopped (unless you forget to set the parking brake on that hill). I believe the terms momentum and inertia are interchangeable. The term “flywheel effect” also refers to these concepts. In a car, there are a number of rotating masses which require energy to accelerate. Up front, ignoring the internal engine components like the crankshaft, we have to worry about the flywheel, clutch assembly, gears, axles, brake rotors and wheel/tire. Out back its a little simpler (for FWD) with just the brakes and wheel/tire contributing most of the mass.
The more mass an object has, the more energy it takes to accelerate it. To accelerate a rolling object such as a wheel, you must both accelerate its mass plus overcome its rotational inertia. As for braking, you must overcome its rotational inertia plus decelerate its mass. By reducing the weight of the vehicle's rotational mass, lightweight wheels provide more responsive acceleration and braking.
Before continuing with our informal analysis here, I want to point out something very important about rotational inertia. We’ve all seen the ice skating move where the skater starts spinning. She pulls her arms in and speeds up, then extends them again and slows down. Why is this? Well, the further a mass is from the center of rotation, the faster it must travel for a given angular speed (how many degrees of an arc it traverses per time unit). The faster anything moves, the more energy it has, so when the arms are pulled in, conservation of energy says that the rotation rate must increase due to equal energy being applied to the same mass over a smaller diameter. Applying this to wheels and tires, which have most of their mass spread as far as possible from the rotation center, I think you’ll agree that it naturally takes more energy to accelerate them. Example: Take a two identical masses, but one is a solid disk of diameter D, the other is a ring of diameter 2D. The ring will require more force to accelerate it (in a rotational manner). Therefore a heavier rim with a smaller diameter could have less rotational mass than a lighter rim of a larger size, and accelerate faster with the same force applied.
The effect of rotating mass can be calculated using Moment of Inertia (MOI). MoI is related to not only the mass of the rotating object, but the distribution of that mass around the rotational center. The further from the center, the higher the MoI. The higher the MoI, the more torque required to accelerate the object. The higher the acceleration, the higher the torque required.
Because of this, the weight of rotating mass such as wheels and tires on a car have a bigger effect on acceleration than static weight such as on the chassis on a car. When purchasing new wheels and tires for a performance car, it can be useful to compare the effects of different wheel and tire combinations. This is especially true when considering upgrading to larger wheels or tires on a car.
The use of light-weight alloys in wheels reduces rotational mass. This means that less energy will be required to accelerate the wheel. Given that each pound of rotational mass lost provides an equivalent performance gain as a 10 pound reduction in vehicle weight, the benefits of light alloy wheels on vehicle performance cannot be overlooked.
For example:
***A reduction in the weight of the rim/tire assembly of 5lbs x 4 (all around the car) is equivalent to a 200lb weight reduction in vehicle weight (thats worth 0.200 in the 1/4 mile)***
So What's the Point?
The point of this discussion is as follows: There is a great deal of rotational mass to deal with in a car and tires and wheels may only make up half of it. Estimates for weight (o.k. for comparison since they’re all in the same gravity field, therefore the mass would be a similar ratio)
Front: Rear:
Wheel/tire: 30-35 lbs each 30-35 lbs each
Flywheel: 15-20 lbs
Clutch: 15 lbs
Halfshafts: 7-10 lbs each
Gears: 5-7 lbs
Rotors: 3-5 lbs 3-5 lbs
Misc: 3-5 lbs 3-5 lbs
------------------------------------------------------------------
Total: 115-148 lbs 76-90 lbs
So a couple pounds here and there on wheels and tires will make a difference, but that difference is magnified because that weight is placed further from the axis of rotation than any other mentioned (remember the ice skater). All these masses must be accelerated, so any reduction is a good thing. Now you know why we always say don't get those 18" rims for your civic. Not only are the heavier, they have a larger overall diameter. Even with lower profile tires, most plus sizing leaves us with a slightly larger wheel.
- Thread starter
- #34
I don't know where this 3" additional width of the Toyo is coming from? Ain't happening, bro
I got it here from the toy site. Does the overall width column mean something else?
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Overall or section width is measured at the widest point of the tire, most times the sidewall, it has little to do with tread width. Toyo & Nitto don't publish tread width.
I really don’t think that the debate is witch tire is better and why but maybe it is witch tire is better for you. I have had Toyo mts for some time now and love them. In my opinion the to are not in the same class to compare quality wise. The Toyo in a 285 is the only off road type tire with a E load rating and the sidewall is just the strongest you will find and seems to be as good or better then the Goodyear MTR in off- road performance and yet it will last longer. The Copper looks almost as close of a copy as they could do without getting into trouble. The load rating, stronger stiffer sidewall, and heavier weight are all better for off-road and safer on road for a rig that can weigh in over 7,000 lbs fully loaded.
But the much narrower width of the copper on a almost 35” tire is good to see because a lot of people have been looking for a good tire that size that have a smaller lift like a 2.5” with ½” spacers up front or J spring because the wider 35” are hitting or rubbing.
Wider Vs. Narrow
It all depends on wow you talk to I think some like narrow some like wide. Personally I would rather have more ground clearance then width however, I am starting to see the advantage in more surface area. Again having more weigh low on the rig is a good thing.
But the much narrower width of the copper on a almost 35” tire is good to see because a lot of people have been looking for a good tire that size that have a smaller lift like a 2.5” with ½” spacers up front or J spring because the wider 35” are hitting or rubbing.
Wider Vs. Narrow
It all depends on wow you talk to I think some like narrow some like wide. Personally I would rather have more ground clearance then width however, I am starting to see the advantage in more surface area. Again having more weigh low on the rig is a good thing.
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i dnot have any discussion points. just thought id say i own the cooper stt and its awesome
thats all
thats all
- Thread starter
- #38
Thanks, I edited post 1 with the widths that seem to be pretty much the same based on what Tim measured. The means that height and weight are the only deltas.
So is the 13-16 lbs additional weight per tire a nit and a non factor.
So is the 13-16 lbs additional weight per tire a nit and a non factor.
Pro:
Better for stability more weight down low on the rig is a good thing
Con:
Harder on the truck and some loss of power to the road.
How much? Don't ask me my friend
Sam
MoJ
Moderator
Ken -
fwiw
I don't have any experience with the Coopers so can't say much about them.
You mention the sidewall is thicker on the Toyos - I didn't see how much - is it enough to make a difference? They're probably both great tires but if the sidewall thickness difference is significant than that would make the choice easy for me. The tread that extends down the sidewall on the Toyo's is pretty thick stuff. Just a swag but it looks like the Toyo siping might be a little better.
I've been happy with the Toyos 315's because they're very well mannered on the road and balanced out great. They don't feel any different than my 305/70 BFG A/T's did as far as handling. I did notice a power loss but it wasn't enough to concern me. If I lived in your area I'm sure I'd regear. If my 80 was my daily driver it might be more of an issue. Bet it won't be a problem with your SC. They weigh more but I figure the Japanese engineers didn't just accidently make that happen. Kind of like our heavy 80's, I assume it was necessary to achieve what was considered a superior design. I like that they're true to their sizing but it doesn't sound like that's a big issue for you. Mine measured 34 15/16th's when mounted on the rim with no weight load. Oh yeah, they're also pretty.
As far as rubbing - I have ome 2.5 medium all around with Mr G 1" up front. The rears will rub at full stuff, no denying it. At first I thought they were just rubbing on the inner flare lip and the mud flap. I trimmed a portion of the inner flare lip and the mud flap, both easy to do with a dremmel. I sanded the inner flare lip smooth with some fine paper. It takes a very close eye to tell that it's been done.
However, after all that they still rubbed. Finally figured out it was rubbing at the top of the wheel well cavity. I sorta expected that all along but wanted to avoid dropping the rear bump stops if I could. I installed Slee's 2 inch rear bump stop extensions and the problem went away. I haven't experimented yet but it may not be necessary to drop the bump stops a full 2". I'd like to play around with some shorter bump extensions and see if I can get back a portion of the rear flex that I lost when lowering the stops. It's probably not that big of a deal as I don't think anyone has ever complained about 80 series being short on rear flex. Despite trying like hell I've been unable to get the fronts to rub which amazes me.
Good Luck!
EDIT: Noticed the first post listed the Toyo load range as D. Just went and looked at the sidewall and mine are marked "LOAD RANGE E"
fwiw
I don't have any experience with the Coopers so can't say much about them.
You mention the sidewall is thicker on the Toyos - I didn't see how much - is it enough to make a difference? They're probably both great tires but if the sidewall thickness difference is significant than that would make the choice easy for me. The tread that extends down the sidewall on the Toyo's is pretty thick stuff. Just a swag but it looks like the Toyo siping might be a little better.
I've been happy with the Toyos 315's because they're very well mannered on the road and balanced out great. They don't feel any different than my 305/70 BFG A/T's did as far as handling. I did notice a power loss but it wasn't enough to concern me. If I lived in your area I'm sure I'd regear. If my 80 was my daily driver it might be more of an issue. Bet it won't be a problem with your SC. They weigh more but I figure the Japanese engineers didn't just accidently make that happen. Kind of like our heavy 80's, I assume it was necessary to achieve what was considered a superior design. I like that they're true to their sizing but it doesn't sound like that's a big issue for you. Mine measured 34 15/16th's when mounted on the rim with no weight load. Oh yeah, they're also pretty.
As far as rubbing - I have ome 2.5 medium all around with Mr G 1" up front. The rears will rub at full stuff, no denying it. At first I thought they were just rubbing on the inner flare lip and the mud flap. I trimmed a portion of the inner flare lip and the mud flap, both easy to do with a dremmel. I sanded the inner flare lip smooth with some fine paper. It takes a very close eye to tell that it's been done.
However, after all that they still rubbed. Finally figured out it was rubbing at the top of the wheel well cavity. I sorta expected that all along but wanted to avoid dropping the rear bump stops if I could. I installed Slee's 2 inch rear bump stop extensions and the problem went away. I haven't experimented yet but it may not be necessary to drop the bump stops a full 2". I'd like to play around with some shorter bump extensions and see if I can get back a portion of the rear flex that I lost when lowering the stops. It's probably not that big of a deal as I don't think anyone has ever complained about 80 series being short on rear flex. Despite trying like hell I've been unable to get the fronts to rub which amazes me.
Good Luck!
EDIT: Noticed the first post listed the Toyo load range as D. Just went and looked at the sidewall and mine are marked "LOAD RANGE E"
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