Correct Tire Size for Stock Restoration

[chuck r]

Hi everyone. I'm nearing completion of a stock restoration of a Series 1 car. Was wondering, if I show it in a stock class, what tire size I can use and not get point deductions? Are all the Gold Medallion cars running the original 175HRx14's? I think I remember finding one place that still sold that size.

Thanks for the help!

[Arne]

Not being a judge, nor ever involved with a Gold Medallion car, I'm not sure how the judges react to a non-stock size tire.

I can say that - assuming you have the correct 4 1/2" wide rims as fitted to all '70 & '71 cars in the US - if you don't use the 175-14 (only made by Vredstein these days, as best I could determine), the only other size that really fits those narrow wheels is 185/75R14. Same overall diameter, 10mm (3/8") wider section width. Considerably more choices in that size. None of them are particularly inspiring tires by today's standards, but the originals wouldn't be either. And in this case we aren't really worried about today's standards anyway - they would just have to fit and look correct.

If you have fitted a set of later steel wheels (either 5" as fitted on '72 through '78 280Zs, or 5 1/2" as fitted to 280ZXs), you could fit 195/70-14 tires. Again, same overall diameter, just a bit wider. It might be worth noting that the Vintage Program cars all got this size tire fitted, although I can't remember which rim size they used.

[26th-Z]

I assume you are talking about the ZCCA 'stock class' as you mention the Gold Medallion award which is exclusve to the Z Car Club Association awarded at the annual convention. The judging manual and rules can be viewed through the downlaod tab of the ZCCA web site; ZCCA.org. They have been revised in 2012 which I had no involvement, however I was actively involved in the comprehensive 2009 revision / update for which the rules for judging the stock class remain the same.

A) STOCK CLASS

Vehicles exhibited must be configured exactly as shipped from factory for all S30 and S130 models (240Z –

280ZX) as special noted. Factory optional ordering packages and options will be allowed for later models (280Z

– 370Z) as special noted. Cars with dealer installed options, including Nissan supported optional parts, such as

wheels, floor mats, body and bumper moldings / trim, etc. can enter this class with a minimum five point

deduction for each case. Any dealer preparation shall be limited to removal of protective shipping coatings /

coverings and installation of components shipped with the car in protective coverings. Air-conditioning must

be factory installed. Replacement of consumable items will be allowed however they must be Nissan

replacement parts for the application to the specific model. Consumable items shall be: battery, oil filter, fan

belts and ignition wires. Other consumable items limited to tires, cooling system hoses, vacuum system hoses,

fuel system hoses, and exhaust system may be allowed at the discretion of the Chief Judge of the car show

however they must be Nissan replacement parts for the application to the specific model. The Chief Judge will

announce this at the judge’s meeting.

So...it wouldn't necessarily be "correct" to use an original size and not an original brand such as Bridgestone or Toyo. I know plenty of people who have collected what I might call show tires specifically for that purpose. The thought being that the point loss for wear or age of an original tire would be less than the automatic 5 point loss for an "aftermarket" brand even though it is the correct size. Then, there's the "cover your arse" statement at the end which includes tires for situations just like this one. Probably what it would boil down to is what the competition is like for the stock classes (all of them competing equally for the Gold Medallion) being judged at the particular convention. A savy competitor would size up the competiton and ask for a ruling at the judges meeting. For instance, if all the cars in the stock classes (elligable for the GM) were running replacement tires the issue would defer to a "correct" size but if one competitor ran "as delivered from the factory" tires, the issue should be brought to the attention of the judges and you can bet that the guy who has gone to all the effort to find as new condition original tires is going to have a loud voice! On the other hand; so you get dinked 5 points for your brand new looking replacement tires. If the rest of your car judges full points, you still qualify for the GM.

Edited December 2, 2012 by 26th-Z

[fixitman]

The Vredestein Spirit Classic is a good quality HR rated tire available in 175 HR-14. I just bought one as a spare. BTW, it fits in the spare tire well, where larger sizes may not. It is still available thru a few Vredstein dealers and Coker Tire. The best price I found was from EuroTire (Bill - 973-575-0080) in northern NJ. EuroTire can arrange for the Vredstein warehouse to drop ship the tires to you.

[Oiluj]

I fully understand the reasoning, but it just "bugs me" that common, dealer installed options like A/C, rear shades, door strips, dual mirrors would automatically result in a points deduction.

Sure I "get it", but if all the U.S. dealers carried the parts and installed them... I remember seeing brand new 240Z's on the showroon floor with sunshades installed. It's how many left the showroom...

I'm out of the game anyway, and non of this applies to my car, but it seems a bit unrealistic...

I'd be willing to bet there are a few "pre-war" cars shown at Pebble Beach with dealer options on them that are considered "stock".

[TomoHawk]

Dealer installed items as "sock" doesn't follow the precedent of being "factory installed," but it's not an owner-installed item either. Should you have "proof" that it was actually dealer installed, and not just bought from the dealer or a retro unit?

The question about it would be one of, "How many or what kinds of dealer-installed items should be allowed?

It looks like another revision of the ZCCA rulebook is needed to take care of this.

As for the Pebble Beach thing: I think those dealer-installed items were more like post-assembly line repairs or corrections.

Edited December 2, 2012 by TomoHawk

[chuck r]

Thanks a bunch for all the help and info. I was intending to use the orig 4.5x14 wheels. Now that you mentioned the brand, that was the manufacture I'd seen. Don't know anything about them. I'm sure they're no match for today's performance tires but its good too know they're a decent tire.

I appreciate the interpretation of the rules. I'd looked at that section. I'd seen the tire listing under the consumable items section and was hoping the ZCCA had settled on a acceptable replacement size. I was visiting with Mike B last summer and he thought this was maybe the case. In my perfect little dream world I could put 195/70x14 on it and everything would be good. Incidently, my car as purchased did have a set of 175HR's on it but old, worn and a no-name brand. Was originally going to junk them but decided to hold on to them until this size issue was settled. Maybe I should consider using them on the original wheels as a car show set.

While we're on the subject of judging- many years ago I did a couple concours Mustangs and was also a concours judge. The rules were you could only judge what you could see. No touching things, no lifting carpet, no moving things in the trunk, etc. Is ZCCA judging the same?

Thanks again for the help.

[TomoHawk]

ZCCA judges seem to do whatever they feel like: http://www.classiczcars.com/forums/thread47138.html

[26th-Z]

One of the unique things about the American export 240Z or HLS30U and UA concerns what the dealers added to the cars to increase their profit margin. In some cases, such as A/C, one might argue that the dealer installed items suited a market demand that was not provided by Nissan Motor Co., Ltd. In all cases, all dealers did not install the same items on all the cars so the arguement of "as sold" isn't really valid. The only non factory item 26th was delivered with was carpeting, surprising as that may sound to some of you. By all looks, 27th was delivered the same, but I don't know 27th's history as well as I know 26th's. Until the 1972 model year, Nissan Motor Co., Ltd. did not officially offer optional equipment in the North American market however Nissan Motors in North America, or Datsun, did repackage and sell optional equipment under the Datsun brand. Quite a bit of it was manufactured by AMCO. I have a small collection of those items including a clip-on vanity mirror for the visor.

There are plenty of car clubs that have far more strict rules concerning originality than the ZCCA. I would suggest that all you guys complaining about dealer installed equipment just want the rules changed to suit your own situation and that isn't fair across the board. I have had plenty of arguements with people about this. It isn't a fair way to judge the historical correctness of the car as all things are not equal across the board to everyone.

The comparison to pre-war cars at Pebble Beach isn't valid either. Those cars are judged on beauty. Purely subjective. Corvettes (Bloomington) on the other hand are subjected to a meticulous inspection involving lifting, touching all all sorts of assultive assessment - read the rules for the National Corvette Restore's Society. Hell, you think you Z guys have it difficult!

I would like to suggest that if any of you really want a trophy, got down to the trophy dealer in your town and have one made. Award yourself top honors and don't forget to mention that you recieved the secret handshake recognition!