Correct tires for my 66/ NCRS correct?

[John R.]

Hello,
I am thinking about getting other tires for my car. I have only had the car for a month and my first mid year car.I was told by a few of my friends that I should swap out my tires as they are old. I am running 7.75 - 15 Bias Ply.They are at least 8 years old with 500 miles on them. They look brand new (pics attached). There isn't really any checking or cracks on the tires.I would like to get my car judged soon in the near feature but debating how much of a deduction I would incur with putting radials on.Do I swap them out when and if I get my car judged????

What would be the correct size radial (205x75x15?) and brand that you would recommend if I go that way?
Thank you.

[Gary B.]

John,

Tire-specific standard deduction guidelines apply when judging tires. Back in 2017 Bob Rosenblatt posted these standard deduction guidelines for tires:

“The NCRS standard deductions for tires are as follows:
4 matching OEM tires and 1 OEM spare no deduction
Reproduction OEM brand with DOT 10% deduct
OEM brand type and size differ slightly from original 20% deduct
OEM brand which differ considerably from original 30% deduct
Non OEM brand having correct size and sidewall specifications 40% deduct
Current day OEM brand service replacement size with correct white wall size 60% deduct
Same as above non OEM brand 75% deduct
For all others or those with white wall mounted inboard 100% deduction”

Rob noted: “Based on that the deduct for radials of an OEM manufacturer would be 60%“

There are 30 points for originality in the tires line item on the judging sheets. So, for Rob’s example of OEM manufacture of radials that would result in an 18 point deduction. You can figure out other deductions for other types of tires based on what Rob listed.

Gary

[Gary B.]

John,

What manufacturer and model are the bias ply tires on the car now? Even though they might be 8 years old, they look pretty nice. Given your description, it sounds like they’ve been protected from the sun and the elements. I’d use them for judging if they are an OEM brand.

Gary

[John R.]

John,

What manufacturer and model are the bias ply tires on the car now? Even though they might be 8 years old, they look pretty nice. Given your description, it sounds like they’ve been protected from the sun and the elements. I’d use them for judging if they are an OEM brand.

Gary

B.F.Goodrich Silvertown is what are on there now. They are really nice. Can they be used for judging?

[Gary B.]

Are they Silvertown 660 or 770? If so, those are one of the OEM brands and models.

If you don’t already have a copy, one of the best investments you can make is a copy of the ‘66 Technical Information and Judging Guides.

Gary

[John R.]

Are they Silvertown 660 or 770? If so, those are one of the OEM brands and models.

If you don’t already have a copy, one of the best investments you can make is a copy of the ‘66 Technical Information and Judging Guides.

Gary

Yes I have the ‘66 Technical Information and Judging Guide.I have glanced through it .Too busy working on it lately. Car sat for 7-8 years.I believe it was a frame off. Needed a new fuel pump and flushed all fluids.

How do you tell if they are 660 or 770.I see a number after 4Ply that is 95S

[Gary B.]

John,

I can only assume the 660 or 770 numbers appear somewhere on the tires. If not, then I think your tires are not the same as the OEM style..

Gary

[Steve B.]

Reproduction BFG silvertown tires do not have the numbers 660 on the sidewall. That is one way to tell if they are repo or OEM. Of course originals have no dot markings on the inside sidewall and have an 8 digit code as opposed to the current 11 digit code.