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TIRES


P 205 / 50 R 17     89 Y     M+S     DOT "UYZEDBC1301"



Click on the numbers to see that each stands for
:

P 205 / 50 R 17     89 Y        M+S       DOT "UYZEDBC1301"






Vehicle Type

P
= Passenger   vehicle type

P = Passenger Car   designed to meet North American passenger car standards
LT = Light Trucks
T = Truck

the lack of a preceding letter means a tire designed for European standards





Nominal Width of Tire
205
= 205 mm wide, sidewall to sidewall   nominal width of tire, in millimeters
           not exactly the same as tread width, but close
           to convert to inches, divide by 25.4





Tire Aspect Ratio
50 = 50%  tire aspect ratio
        the sidewall height, expressed as a percentage of the tread width
        in this case, 50% of 205mm = 102mm

• higher aspect ratios provide a softer ride
• lower aspect ratios have a faster response and a rougher ride

aspect ratio      qualities
70-75                low cost tire, less precise turn-in, lower stability at high speeds
65                     common profile, compromise between precision and comfort
60                     slightly more precise and harder riding
50-55                high performance, increased precision and grip
45 and lower    high performance, wears quickly





Tire Type
R
= Radial    tire type

R = Radial - the cords of the belting are perpendicular to the tire tread
D = Diagonal -
B = Bias belted




Wheel Diameter

17
= 17"   wheel diameter
, in inches





Load Index

89
= load index
        a measure of the load a properly inflated tire can carry

65 = 639 lbs.
66 = 661 lbs.

88 = 1235 lbs.
89 = 1279 lbs.
90 = 1323 lbs.
91 = 1356 lbs.
92 = 1389 lbs.
93 = 1433 lbs.
94 = 1477 lbs.

149 = 7165 lbs.
150 = 7385 lbs.





Speed Rating
Y
= Y speed rated   speed rating

           Speed Ratings - sustained speed, in miles per hour
B
= 50 km/h = 31 mph
C
= 60 km/h = 37 mph
D
= 65 km/h = 40 mph
E
= 70 km/h = 43 mph
F
= 80 km/h = 50 mph
G
= 90 km/h = 56 mph
J
= 100 km/h = 62 mph
K
= 110 km/h = 68 mph
L
= 120 km/h = 75 mph
M
= 130 km/h = 81 mph
N
= 140 km/h = 87 mph
P
= 150 km/h = 93 mph
Q
= 160 km/h = 99 mph
R
= 170 km/h = 106 mph
S
= 180 km/h = 112 mph
T
= 190 km/h = 118 mph
U
= 200 km/h = 124 mph
H
= 210 km/h = 130 mph
V
= 240 km/h = 149 mph
"Ultra-High Performance Tires":
W
= 270 km/h = 169 mph
Y = 300 km/h = 188 mph
Z = ZR = >240 km/h = >150 mph






M+S
= Mud + Snow






DOT Tire Specification
DOT "UYZEDBC1301"
= U.S. DOT (Department of Transportation) Tire Specification
                                             this code can be used in the event of a tire recall

UY = Plant Code
ZE = Tire Size
DBC = Compound Structure Code optional
13 = the week manufactured (13th week of the year)
01 = the year manufactured (01 = 2001) don't purchase tires that are more than a couple of years old






Traction and Temperature Ratings

Traction   a measure of wet stopping ability

AA = best
C = worst


Temperature   resistance to high temperatures

A = best
C = worst





Tread-Wear Rating


A tire rated 800 should last twice as long as a tire rated 400.

A tire rated 400 should last twice as long as a tire rated 200.


Winter tires do not carry a Tread-Wear Rating.

According to the guidelines of the SCCA (Sports Car Club of America), tires with a treadware
rating of 140 or greater are considered "street" tires.  Softer tires are considered "race" tires.







1966 PORSCHE 912

TIRES & WHEELS
The Porsche 912
uses equal size tires front and rear

quotes:
going to 185/65R15 throws speedometer off 10 mph
912 with original 5.5x14 wheels is running 205/60HR14 all around
my SWB 912 loves 185/65
195/65 work on swb 912s
on 4.5x15 wheels => 185/70VR15 Yoko A321 tires ('67 912)
a 1966 with 6" Fuchs wheels:
   185/65/15 => no rub
   185/70/15 => rub
as far as wheel height is concerned, 195/60/15 = 185/65/15
a 185 on a 4.5" wheel is pushing it, 185 better off using a 5.5" wheel
195 is top limit on 5.5" wheels
6" rims are good for 185->205
a 205 tire should be on a 7" rim
195/65x15 works with 5.5" wheels on a 1967
Dunlop SP A2 185/65R15 on 4.5" wheels on a 1965 gets a slight inner tire rub on full turns
a 215 is one inch wider than a 185/70
a 215 is 1/5" wider than a 205/60
do not use 215 in front - it will touch fender during turns
205x60 will work on 5.5" rims & will clear narrow-bodied 912
195x65 closer in size and appearance to original, try Tire Rack
Hoosier Vintage TD 5.50x15 tire equivalent of 185x70 period correct Bias Ply (non-radial)
    illegal for street use (not DOT approved) = default race tire the 356 racers use

on a 1966 912 with 6" Fuchs:
  185/65/15 doesn't rub
  185/70/15 rubs

tire height & wheel diameter
185/70/15 => 70% of 185mm = 129.5mm tire height   ///   640mm = 25.2" wheel diameter
195/65/15 => 65% of 195mm = 126.75mm tire height   ///   635mm = 25" wheel diameter
185/65/15 => 65% of 185mm = 120.25mm tire height   ///   622mm = 24.5" wheel diameter
195/60/15 => 60% of 195mm = 117mm tire height   ///   615mm = 24.2" wheel diameter

real life examples:
Hoosier Vintage 5.50x15 => 24.7" diameter / 7.7" section width (627mm / 196mm) [4.5"-7" rim]

Michelin XZX 165 SR 15 => 25.4" diameter (646mm / 167mm)
B.F. Goodrich 165 R 15 => 25.4" diameter (645mm)
***
165SR15 B.F.Goodrich W/W 635mm diameter / 161mm section width
165SR15 Dayton W/W 635mm / 161mm
165SR15 Michelin XZX 646mm / 167mm
165SR15 Firestone F560 646mm / 167mm
165HR15 Vredestein Classic 645mm / 165mm (25.4" / 6.5") my car originally came with 165HR15 tires
165HR15 Michelin XAS 646mm / 167mm (25.4" / 6.6") my car originally came with 165HR15 tires
165SR15 Vredestein 645mm / 165mm
180HR15 Michelin XAS 680mm / 175mm
185/70HR15 Avon CR6ZZ 635mm / 187mm
185/70VR15 Michelin XWX 641mm / 189mm
185/70HR15 Vredestein Classic 650mm / 188mm
***
Michelin XWX 185/70 VR 15 => 25.5" diameter
B.F. Goodrich P185/70 R 15 => 25.2" diameter

Pirelli P6000 195/65 ZR 15 => 25.1" diameter (638mm) 19lbs. $113.

Hoosier P185/65 R 15 => 24.2" diameter / 7.6" cross section (615mm / 193mm)

a treadware rating of 140 (or 200?) is required to avoid penalization in SCCA solo

Hoosier Vintage TD 5.50-15 dimensions:
   tread width 6.5"
   diameter 24.7"
   circumference 77.6"
   rim 4.5"-7"
   measured rim 4.5"


TIRE OPTIONS for 4.5"x15" rims:
165/15:
Vredestein http://www.vredestein.com/
      - Sprint Classic 165 HR 15   86H
      - Sprint 165 HR 15 $89
Michelin
       - XZX 165 SR 15 $137   diameter 25.40 / cross section 6.40

185/70x15:
Michelin
      - XWX 185/70 VR 15 $301  diameter 25.50 / cross section 7.70
Vredestein
      - Spirit Classic
      - Sprint +

sizes:
closest to 165/15 => 185/70x15 & 195/65x15
recommended => 185/70x15 & 185/65x15


TIRE OPTIONS for 5.5"x15" rims:
195/65x15:
      - Pirelli P6000 $113 diameter 25.10 / section width 8.0 / 19lbs.




1966 Porsche 912
tires on (5) 5.5Jx15 “gas burner” magnesium rims:

Pirelli P6000
195/65 ZR15    91W   SL   N1 (Porsche)
TREADWEAR 180
TRACTION A
TEMPERATURE A
weight = 8.6kg / 19 pounds

UTQG 180 A A
Max Load 1356 lbs.
Max Inflation Press. 51 psi
Tread Depth 10/32"
Tire Weight 19 lbs.
Rim Width Range 5.5-7"
Meas Rim Width 6"
Sect Width 8"
Tread Width NA
Overall Diam. 25.1"
Revs Per Mile 829




tires on (4) 4.5Jx15 steel rims:
?


spare tire on 4.5Jx15 steel rim:
Delta Eurosport 165R15 radial



previous tires on (4) 4.5Jx15 steel rims:
Dunlop SP 20 A/S METRIC
165R15   86S
MAX LOAD 530 KG (1169 LBS) AT 240 kPA (35 PSI) MAX PRESS
M&S TUBELESS
TREADWEAR 400
TRACTION A
TEMPERATURE A
SIDEWALL: 2 PLY POLYESTER
4 PLIES UNDER TREAD: 2 PLY POLYESTER + 2 PLIES STEEL
P058D5-A
CR3174-2
MADE IN NEW ZEALAND

current tires on (4) 5.5Jx15 magnesium rims:
Pirelli P6000
195/65ZR15
contact patch (measured by parking on pieces of paper) is 5"
Subaru Outback
tires:

BRIDGESTONE POTENZA RE950
P225/60R16   97H
M+S
TUBELESS STEEL BELTED RADIAL
TREADWEAR 400
TRACTION A
TEMPERATURE A
DOT H4A6 DFB1303



WHEELS
the OEM wheels are:
4½" x 15" silver painted steel wheels
tires are Dunlop SP 20 A/S METRIC 165R15 86S       in good condition.

my spare is:
silver painted steel wheel, marked "4½ Jx15", "6053A", "3.9", a circle with date 7/65, and a
   circle with the letters KpZ
the mounted spare tire is a old yet unused/new Delta Eurosport 165R15 radial

options in 1966 for the Porsche 912:

4.5x15 Steel, painted silver what my car was ordered with - weigh 17.1 pounds
4.5x15 Steel, chrome-plated
4.5x15 Fuchs Alloys [901.361.012.01]
steel wheels were either made by Lemmerz or KPZ

other options to consider:
4.5x15 Fuchs Alloys [901.361.012.01] as seen on 1967 911
5.5x15 Fuchs Alloys [901.361.012.04] as seen on 1968 911
5.5x15 Mahle Magnesium "Gas Burners" [901.361.017.00] as seen on the 1970-1972 914/6
        @ 9.7 lbs each, lightest wheels ever sold on a Porsche
        offset is 35


   from Pelican Parts:
"These wheels were optional on the 914-6, and are generally pretty difficult to find. Additionally, the five-lug
Mahle alloy is the lightest Porsche alloy ever made, and is consequently very sought after by racers who want
to lighten their car.
This wheel is sometimes called a gas-burner in reference to it's resemblance to a kitchen gas burner stove."

Mahle's wheelwerks became independent and is now BBS Kraftfahrzeugtechnik AG.


5.5x15 steel, 165 HR 15 tires as seen on the 1970 911T
5.5x14 Fuchs, 185 HR 14 as seen on the 911E
4.5x15 steel, 155 SR 15 as seen on the 1970-1972 914/4
5.5x15 steel, 165 SR 15 optional on the 1971 914/4

Fuchs = Fox in German





factors involved in how a car handles

1. grip level - how the car holds the road
2. steady-state balance - mid-corner balance
3. transitional balance - corner enty and exit balance

oversteer - the rear end breaks loose before the front end
understeer - the front end breaks loose before the rear end

a zip tie-on on the shock shaft can tell you how much suspension travel you're getting

1. grip is controlled by
-tire pressure


2. steady-state balance is controlled by
-weight balance
-sway bars
-springs
-alignment











PV = nRT

P = Pressure
T = Temperature






 




MOTOR VEHICLE ENDORSEMENT

DEFINITIONS

The definition of "motor vehicle" is replaced with the following:

     "motor vehicle", when used in Section II of this policy,
     means:

     a. a land motor vehicle designed for travel on public
         roads or subject to motor vehicle registration;

     b. a trailer or semi-trailer designed to travel on public
         roads and subject to motor vehicle registration;

     c. a "recreational vehicle" while off an insured location.
         "Recreational vehicle", means a motorized vehicle
         designed for recreation principally off public roads
         that is owned or leased by an insured. This includes,
         but is not limited to, a motorized all terrain vehicle,
         ambhibious vehicle, dune buggy, go-cart, golf cart,
         snowmobile, trailbike, minibike and personal assistive
         mobility device;

     d. a "locomotive" while off an insured location. "Loco-
         motive" means a self-propelled vehicle for pulling or
         pushing freight or passenger cars on tracks that is
         large enough to carry a person and is owned or
         leased by an insured;

     e. a bulldozer, track loader, backhoe, high-hoe, tren-
         cher, grader, crane, self-propelled scraper, excava-
         tor, pipe-layer, cherry picker, telehandler, logging
         vehicle, mining vehicle or road building vehicle that is
         owned or leased by an insured while off an insured
         location
;

      f. any vehicle while being towed or pushed by or carried
         on a vehicle included in a., b., c., d. or e.;

     g. the following are not motor vehicles:

         (1) a motorized land vehicle in dead storage on an
              insured location;

         (2) a boat, camp, home or utility trailer not being
              towed or pushed by or carried on a vehicle
              included in a., b., c., d. or e.;

         (3) a motorized golf cart while used for golfing pur-
              poses;

         (4) a motorized vehicle or trailer designed to assist
              the handicapped that is not designed for travel on
              public roads or subject to motor vehicle registra-
              tion;

     h. "leased" does not include temporary rental.

All other policy provisions apply.




FUEL OIL EXCLUSION ENDORSEMENT


The insurance provided under coverage L does not apply to bodily injury or property damage arising
out of the actual, alleged or threatened discharge, seepage, leakage, migration, dispersal, spill, release,
emission, escape, leaching or disposal of fuel oil.

All other policy provisions apply.

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