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dynolou2
03-06-2007, 10:35 PM
For a 62 Hawk GT what modern size corresponds to the 670-15 old bias ply, in a radial. Thanks Lou[8D]

Dick Steinkamp
03-06-2007, 10:40 PM
quote:Originally posted by dynolou2

For a 62 Hawk GT what modern size corresponds to the 670-15 old bias ply, in a radial. Thanks Lou[8D]


Here's Coker's conversion chart...

http://resources.coker.com/tire-tech/tire-installation/bias-ply-to-radial-conversion-chart.html



http://thenobot.org/images/s2d/s2d_01.jpg

53k
03-07-2007, 11:20 AM
quote:Originally posted by Dick Steinkamp


quote:Originally posted by dynolou2

For a 62 Hawk GT what modern size corresponds to the 670-15 old bias ply, in a radial. Thanks Lou[8D]

Here's Coker's conversion chart...
http://resources.coker.com/tire-tech/tire-installation/bias-ply-to-radial-conversion-chart.html

I'm not quarreling with Dick's answer, but I disagree with Coker's conversion. I think they are covering themselves against anyone mounting a larger tire on a stock wheel. A 205x75x15 is enough "shorter" (smaller in diameter) to throw off your speedometer quite a bit. I found that a 225x75 is virtually the same height as a 6.70, but it is much too wide for a stock wheel and can cause some rubbing problems even on a wider wheel (I ran 225s on 6.5 inch MoPar wheels on my '64 Avanti with no clearance problems except when turning and hitting a bump at the same time). IMHO a 215x75x15 is a good compromise (on a wider rim). This picture shows from right to left a 205x75x15, a NOS 6.70x15 (not repro), and a 225x75x15. http://www.frontiernet.net/~thejohnsons/225,%20670,%20205.JPG


[img=right]http://www.frontiernet.net/~thejohnsons/Forum%20signature%20pix/R-4.JPG[/img=right][img=right]http://www.frontiernet.net/~thejohnsons/Forum%20signature%20pix/64L.JPG[/img=right][img=right]http://www.frontiernet.net/~thejohnsons/Forum%20signature%20pix/64P.jpg[/img=right][img=right]http://www.frontiernet.net/~thejohnsons/Forum%20signature%20pix/53K.jpg[/img=right]Paul Johnson
'53 Commander Starliner (since 1966)
'64 Daytona Wagonaire (original owner)
'64 Daytona Convertible (2006)
Museum R-4 engine

MagikDraggin
03-07-2007, 02:32 PM
quote:
I'm not quarreling with Dick's answer, but I disagree with Coker's conversion. I think they are covering themselves against anyone mounting a larger tire on a stock wheel. A 205x75x15 is enough "shorter" (smaller in diameter) to throw off your speedometer quite a bit. I found that a 225x75 is virtually the same height as a 6.70, but it is much too wide for a stock wheel and can cause some rubbing problems even on a wider wheel (I ran 225s on 6.5 inch MoPar wheels on my '64 Avanti with no clearance problems except when turning and hitting a bump at the same time). IMHO a 215x75x15 is a good compromise (on a wider rim). This picture shows from right to left a 205x75x15, a NOS 6.70x15 (not repro), and a 225x75x15. http://www.frontiernet.net/~thejohnsons/225,%20670,%20205.JPG


Some interesting information. What is the width of the OEM wheels? And while I'm thinking of it, if you happen to know, what is the offset of the factory wheels?

You say you had some "contact" issues with the 6.5" Mopar wheels/tires....contact where, if I may ask? Front only or on the rear also? And would the same sort of clearence issues be present on a '62 Hawk?

And finally, last but not least....do you see any problem with going to a somewhat smaller sidewall height (like say a 45) on a little larger diameter wheel in order maintain the same overall height, with say a 6.5" dia wheel.

Sorry for all the questions.....I'm new at this.

http://img.photobucket.com/albums/v147/MagikDraggin/Other%20Stuff/62StudebakerGTHawk1-small.jpg
1962 GT Hawk 4sp

N8N
03-07-2007, 04:08 PM
Look at the interchange document on my web site, I've attempted to include width and offset info. for all the factory wheels that I've had a chance to measure. To specifically answer your question, Hawk wheels were either 5" wide (early style or "Super Hawk") or 4.5" (late, non-"super") the early 5" wheels were about 3/4" offset, don't recall off the top of my head what the late ones were (and I don't have access to my own web site from work)

If anyone can help me flesh out that table with more or better info, I'd appreciate it.

nate

--
55 Commander Starlight
http://members.cox.net/njnagel

hank63
03-08-2007, 08:29 AM
Every tire has a "rolling radius" or "rolling diameter". To avoid messing up the speedo, get a tire with the same (or close) rolling diameter as the old one. Tire manufacturers publish these numbers, your local tire shop should be able to dig 'em out for you.
On my brand X, I went from 5.90 x 17 to 205 x 16 (series 85) and ended up with a rolling diameter change of about 3mm (mind you, I also needed wider rims).
/H

Dick Steinkamp
03-08-2007, 09:29 AM
quote:Originally posted by MagikDraggin

And finally, last but not least....do you see any problem with going to a somewhat smaller sidewall height (like say a 45) on a little larger diameter wheel in order maintain the same overall height, with say a 6.5" dia wheel.



IMHO, there are very few older cars that the "rubber band" type tires and large diameter wheels look good on. I did see a few 30's hot rods at the Seattle Roadster show that looked fine with them, but they were BIG bucks cars by big name builders with reshaped wheel wells and other substantial changes that helped them look right.

Again, IMHO, that "look" fits fine on the cars that were designed for it...late model BMW's, Corvette's, etc. The wheel well opening, lip, body shape, stance, suspension design, wheel offset all works together and looks right.

On a car like your Hawk, to me they just look silly. They don't fit the design and style of the car. They don't fit in the wheel well. Usually the car ends up looking like it is on its tip toes. If the car is lowered enough to try to make it look even somewhat correct, you run into clearance problems.

Just my 2 cents. I'm somewhat "old skool" :)

http://thenobot.org/images/s2d/s2d_01.jpg

MagikDraggin
03-08-2007, 12:15 PM
quote:Originally posted by Dick Steinkamp
IMHO, there are very few older cars that the "rubber band" type tires and large diameter wheels look good on.
On a car like your Hawk, to me they just look silly. They don't fit the design and style of the car. They don't fit in the wheel well. Usually the car ends up looking like it is on its tip toes. If the car is lowered enough to try to make it look even somewhat correct, you run into clearance problems.

Just my 2 cents. I'm somewhat "old skool" :)



Old skool, ehh? Well, I guess I'm a little bit of both. I have tried and tried to mentally visualize what the Hawk would look like with those sorts of tire/wheel combinations. But honestly, I kinda like the way it looks now, with the wide Coker whites and factory full wheel covers.

Your 2 cents worth and opinion are very valuable to me. Enough that it has served to convince me to, leave "wheel enough" alone, heh, heh, heh.

Karl


http://img.photobucket.com/albums/v147/MagikDraggin/Other%20Stuff/62StudebakerGTHawk1-small.jpg
1962 GT Hawk 4sp