New rear tires or full set? 12/11 Update!
12-09-2011, 04:13 PM
#16
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I use this online tool to check tire sizes. Very useful:
http://www.miata.net/garage/tirecalc.html
In your case the width difference between 205/55 and 205/45 is negligable, but the diameter difference is 24.9 inches versus 23.3 inches...so essentially what you have now is lowering the front of your car .8 inches. It might also make your wheel/tire look relatively small compared to the wheel well opening. But it won't hurt anything to run it.
http://www.miata.net/garage/tirecalc.html
In your case the width difference between 205/55 and 205/45 is negligable, but the diameter difference is 24.9 inches versus 23.3 inches...so essentially what you have now is lowering the front of your car .8 inches. It might also make your wheel/tire look relatively small compared to the wheel well opening. But it won't hurt anything to run it.
12-09-2011, 04:41 PM
#17
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I use this online tool to check tire sizes. Very useful:
http://www.miata.net/garage/tirecalc.html
In your case the width difference between 205/55 and 205/45 is negligable, but the diameter difference is 24.9 inches versus 23.3 inches...so essentially what you have now is lowering the front of your car .8 inches. It might also make your wheel/tire look relatively small compared to the wheel well opening. But it won't hurt anything to run it.
http://www.miata.net/garage/tirecalc.html
In your case the width difference between 205/55 and 205/45 is negligable, but the diameter difference is 24.9 inches versus 23.3 inches...so essentially what you have now is lowering the front of your car .8 inches. It might also make your wheel/tire look relatively small compared to the wheel well opening. But it won't hurt anything to run it.
Great info, thanks!
12-09-2011, 05:28 PM
#18
Race Car
If I may be the devil's advocate here. I agree with all stated above...primarily the safety issue. Now the wrong size tires will not give up and leave you in a ditch, but ride and handling will be severely affected. Furthermore, the area inside the tire that's occupied by air is critical in cooling the tire and determines how the tire responds to tire pressures and the constant flexing of the sidewall. This can get a bit technical, but I would want the correct size tire on the rim. I'm a little surprised that the shop that sold/brokered the car would let a buyer fly in and drive the car for 2200 miles with the wrong size tires. I would never put that size tire on a 911, and would demand they be correct under my watch of the car weather I owned, were selling, or servicing the car. If nothing else, the car will ride like crap, and will disrupt handling quickly as you approach the limits of the chassis in spirited driving. Plus they look silly.
The second number in the tire size is the aspect ratio. It is the percentage of the width(the first number in millimeters...205 in this case) that denotes the hight of the sidewall from the rim. .8 of an inch may not sound like a lot, but it is when it comes to sidewall flex and the handling/ride of the car.
As for the Porsche factory tire recommendations, take it for what it's worth. It's like their oil recommendations; subject to supplier contracts. According to the factory, we should all be running 0w-40 oil in any production Porsche. Yea, sure...I'l believe it when I see them dumping Mobile1 0w/40 in 356/1 or a 356 Carrera 4 cam, or a 911RS or any other vintage Porsche in their museum collection. Bridgestones are outstanding tires IMO. The torsion bar 911 likes a rounded sidewall and tread corners which is hard to find in todays high performance tires. There is lots of debate on this issue and a visit to the search function may be needed.
Bottom line, I would put a complete set of tires on the car after reading the recommendations and experience of others. It will make you very happy with your new 911 in a number of different ways including the way it drives/rides and looks.
The second number in the tire size is the aspect ratio. It is the percentage of the width(the first number in millimeters...205 in this case) that denotes the hight of the sidewall from the rim. .8 of an inch may not sound like a lot, but it is when it comes to sidewall flex and the handling/ride of the car.
As for the Porsche factory tire recommendations, take it for what it's worth. It's like their oil recommendations; subject to supplier contracts. According to the factory, we should all be running 0w-40 oil in any production Porsche. Yea, sure...I'l believe it when I see them dumping Mobile1 0w/40 in 356/1 or a 356 Carrera 4 cam, or a 911RS or any other vintage Porsche in their museum collection. Bridgestones are outstanding tires IMO. The torsion bar 911 likes a rounded sidewall and tread corners which is hard to find in todays high performance tires. There is lots of debate on this issue and a visit to the search function may be needed.
Bottom line, I would put a complete set of tires on the car after reading the recommendations and experience of others. It will make you very happy with your new 911 in a number of different ways including the way it drives/rides and looks.
12-09-2011, 09:28 PM
#19
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Tires are the number one piece of safety equipment on your car.
1) Always replace your tires with the most expensive ones the dealer has on hand. Otherwise, you're asking for a blow-out at 80mph, which is not easy to recover from, and could harm you and your loved ones.
2) Always replace all of the tires on the car -- and on all of your other cars -- and your spares -- at the same time. Otherwise the tread depths simply will not match. You don't get a hair cut on just one side of your head, do you?
I'm kidding, of course. But for some reason the tire industry (like the mattress industry) has a lot of people convinced of a lot of voodoo.
For a street-driven car, you can run just about any combination of 205/225 tires and be fine. Your tire pressures will be more important, safety-wise, than the brand of tire. And even on pressures, it's easy to get carried away.
1) Always replace your tires with the most expensive ones the dealer has on hand. Otherwise, you're asking for a blow-out at 80mph, which is not easy to recover from, and could harm you and your loved ones.
2) Always replace all of the tires on the car -- and on all of your other cars -- and your spares -- at the same time. Otherwise the tread depths simply will not match. You don't get a hair cut on just one side of your head, do you?
I'm kidding, of course. But for some reason the tire industry (like the mattress industry) has a lot of people convinced of a lot of voodoo.
For a street-driven car, you can run just about any combination of 205/225 tires and be fine. Your tire pressures will be more important, safety-wise, than the brand of tire. And even on pressures, it's easy to get carried away.
Shouldn't you also have the entire neighborhood or town, if small enough, change their tires and the tires on all of their kid's play toys at the same time to assure a reasonable level of "known" safety within said Porsche owner's community???
(My Life!)
12-10-2011, 10:03 AM
#21
the fronts are probrobly fine. id just look at the age on the dot stamp. if theyre more than 6 or 7 years old your probrobly better off replacing them all. especially since its from the south
12-10-2011, 01:47 PM
#23
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this is a great opportunity to train your wife as well....
see if you get one tire fixed for $30 she will think this is going to be a cheap car and when you tell her an oil change at home cost $100 she might go ballistic
on the other hand if you get a full set of tires because you "had a flat" and it cost north of $600 the oil changes will seem like a bargain...
Porsche/wife philosophy 101
see if you get one tire fixed for $30 she will think this is going to be a cheap car and when you tell her an oil change at home cost $100 she might go ballistic
on the other hand if you get a full set of tires because you "had a flat" and it cost north of $600 the oil changes will seem like a bargain...
Porsche/wife philosophy 101
12-10-2011, 01:50 PM
#24
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[quote=Fonz0;9090784]ROTFL. Also, make certain to have all potholes in a 3 state radius patched before you leave your driveway.
New England is like 7 states so I think we need to expand! I knew I was getting closer to home by how bad the roads were getting!
I think you and Birdman are right. For the extra $400 it will be worth it to establish a baseline on the tires and start off on the right foot!
New England is like 7 states so I think we need to expand! I knew I was getting closer to home by how bad the roads were getting!
12-10-2011, 05:25 PM
#25
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this is a great opportunity to train your wife as well....
see if you get one tire fixed for $30 she will think this is going to be a cheap car and when you tell her an oil change at home cost $100 she might go ballistic
on the other hand if you get a full set of tires because you "had a flat" and it cost north of $600 the oil changes will seem like a bargain...
Porsche/wife philosophy 101
see if you get one tire fixed for $30 she will think this is going to be a cheap car and when you tell her an oil change at home cost $100 she might go ballistic
on the other hand if you get a full set of tires because you "had a flat" and it cost north of $600 the oil changes will seem like a bargain...
Porsche/wife philosophy 101
I think I'll use the latter example. She's pissed off enough already so getting her use to spending $$$ on it won't hurt things much more!
12-10-2011, 07:34 PM
#26
While you may find a set of matching rears on Ebay, I would consider a full set of Falkens, and you could look for Vulcan Tire on a Google search if you want a good price, less than 400 a set.
I like you Tim, but I will have to tell you tat MANY people have come on this forum searching to cure ill handling Porsche issues, only to find that they screwed up by not getting a set of matching tires. The engine is in the rear of your car, in case you did not notice, and this makes the rear very heavy, and the front very light. I DNGAF what your neighbor runs on his clapped out Chevy Nova, but I can tell you I will have no sympathy for you if you do not make an attempt to listen to the advice given to you here, or use the search function.
Tires for our cars are cheap for a decent quality tire. Many 911 owners who will otherwise lavish care and attention on their car will often cheap out on tires. Running a fresh matching set is ALWAYS recommended on 911s.
ALWAYS. Also, joining the PCA and doing a few DE events would be highly to your advantage, if you want to know your car better.
BTW, I just purchased a 2001 Impreza as a winter car for my wife. It had mismatched tires, and a STRONG pull to the left under acceleration, almost as if the front end was screwed up. A new set of tires, and the car drives like new. No pull, and very nice handling.
Of course, if you put a used tire on there, and saved your pennies for spring, no one would fault you.
I like you Tim, but I will have to tell you tat MANY people have come on this forum searching to cure ill handling Porsche issues, only to find that they screwed up by not getting a set of matching tires. The engine is in the rear of your car, in case you did not notice, and this makes the rear very heavy, and the front very light. I DNGAF what your neighbor runs on his clapped out Chevy Nova, but I can tell you I will have no sympathy for you if you do not make an attempt to listen to the advice given to you here, or use the search function.
Tires for our cars are cheap for a decent quality tire. Many 911 owners who will otherwise lavish care and attention on their car will often cheap out on tires. Running a fresh matching set is ALWAYS recommended on 911s.
ALWAYS. Also, joining the PCA and doing a few DE events would be highly to your advantage, if you want to know your car better.
BTW, I just purchased a 2001 Impreza as a winter car for my wife. It had mismatched tires, and a STRONG pull to the left under acceleration, almost as if the front end was screwed up. A new set of tires, and the car drives like new. No pull, and very nice handling.
Of course, if you put a used tire on there, and saved your pennies for spring, no one would fault you.
12-10-2011, 08:10 PM
#27
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Welcome to the world of "while you're in there...."........do check your calipers, rotor (spec ok?) and pads......how do the brake lines look?.......(original?),..----you get the drift, in being "thorough"...
Rubber? Gotta' be fresh (obviously matched) or all bets are off!!!!!!!!!!-in your case-
BRAND NEW RUBBER!!!!!!!!!! MAYBE SANTA IS LISTENING?
Doyle
Rubber? Gotta' be fresh (obviously matched) or all bets are off!!!!!!!!!!-in your case-
BRAND NEW RUBBER!!!!!!!!!! MAYBE SANTA IS LISTENING?
Doyle
12-11-2011, 10:18 AM
#28
Instructor
Tires
I just had a similar situation. I found a flat front tire (cheap Kuhmos) and chose to replace all four with Conti DW, 205 55 front and 225 50 rear on sevens and nines (few choices in 245 45 16). I only have about a thousand miles on them, but I am very pleased. Took her for a spin (figuratively) in the rain and they were great.
Larry in Georgia
1988 Carrera Targa
1991 Volvo 740 wagon (mit V8 conversion)
1967 Chevy C 10
2003 Audi A4 Avant (wifey)
Past:
5 Audi
7 Alfa
1 '66 Chrysler Newport (Grandma's)
Larry in Georgia
1988 Carrera Targa
1991 Volvo 740 wagon (mit V8 conversion)
1967 Chevy C 10
2003 Audi A4 Avant (wifey)
Past:
5 Audi
7 Alfa
1 '66 Chrysler Newport (Grandma's)
12-11-2011, 10:37 AM
#29
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While you may find a set of matching rears on Ebay, I would consider a full set of Falkens, and you could look for Vulcan Tire on a Google search if you want a good price, less than 400 a set.
I like you Tim, but I will have to tell you tat MANY people have come on this forum searching to cure ill handling Porsche issues, only to find that they screwed up by not getting a set of matching tires. The engine is in the rear of your car, in case you did not notice, and this makes the rear very heavy, and the front very light. I DNGAF what your neighbor runs on his clapped out Chevy Nova, but I can tell you I will have no sympathy for you if you do not make an attempt to listen to the advice given to you here, or use the search function.
Tires for our cars are cheap for a decent quality tire. Many 911 owners who will otherwise lavish care and attention on their car will often cheap out on tires. Running a fresh matching set is ALWAYS recommended on 911s.
ALWAYS. Also, joining the PCA and doing a few DE events would be highly to your advantage, if you want to know your car better.
BTW, I just purchased a 2001 Impreza as a winter car for my wife. It had mismatched tires, and a STRONG pull to the left under acceleration, almost as if the front end was screwed up. A new set of tires, and the car drives like new. No pull, and very nice handling.
Of course, if you put a used tire on there, and saved your pennies for spring, no one would fault you.
I like you Tim, but I will have to tell you tat MANY people have come on this forum searching to cure ill handling Porsche issues, only to find that they screwed up by not getting a set of matching tires. The engine is in the rear of your car, in case you did not notice, and this makes the rear very heavy, and the front very light. I DNGAF what your neighbor runs on his clapped out Chevy Nova, but I can tell you I will have no sympathy for you if you do not make an attempt to listen to the advice given to you here, or use the search function.
Tires for our cars are cheap for a decent quality tire. Many 911 owners who will otherwise lavish care and attention on their car will often cheap out on tires. Running a fresh matching set is ALWAYS recommended on 911s.
ALWAYS. Also, joining the PCA and doing a few DE events would be highly to your advantage, if you want to know your car better.
BTW, I just purchased a 2001 Impreza as a winter car for my wife. It had mismatched tires, and a STRONG pull to the left under acceleration, almost as if the front end was screwed up. A new set of tires, and the car drives like new. No pull, and very nice handling.
Of course, if you put a used tire on there, and saved your pennies for spring, no one would fault you.
Welcome to the world of "while you're in there...."........do check your calipers, rotor (spec ok?) and pads......how do the brake lines look?.......(original?),..----you get the drift, in being "thorough"...
Rubber? Gotta' be fresh (obviously matched) or all bets are off!!!!!!!!!!-in your case-
BRAND NEW RUBBER!!!!!!!!!! MAYBE SANTA IS LISTENING?
Doyle
Rubber? Gotta' be fresh (obviously matched) or all bets are off!!!!!!!!!!-in your case-
BRAND NEW RUBBER!!!!!!!!!! MAYBE SANTA IS LISTENING?
Doyle
12-11-2011, 10:42 AM
#30
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Think I'm going to go with the Michelin Exalto's since they are in Porsche's recommended booklet which Pavegeno so graciously provided and the set that is on the car already provides a nice firm, smooth ride. Will also do Doyle's checklist if not for anything else to familiarize myself with these patrs. Thanks again and Happy Sunday!