I have a 63' Dart all stock except for the 14" rims I purchased from a guy who took them off his 60's Barracuda. When tire searching using the calculator, it advises not to exceed 3.3% of original tire size because one might experience brake failure. The rims I got have 195/75/14 on them and I've been running these tires for a month now, I like the diameter and it looks nice although when I replace these older tires I'm thinking of 195/65/14 not much difference but still more than advised increase. Since I haven't experienced any braking problems with these larger tires what are my chances later on? Does this brake failure they speak of pertain to drum, disk or both and what is the failure ?
My grandmother's 74' Valiant has 195/70/14, I'm curious.
Thanks for the read,
Brian

Your grandmother's Valiant likely has front disks and 10" rear drums rather than the 9" drums all around like the 63. The problem with ovesize tires on inadequate brakes is that the larger diameter increases rotational momentum. 195/70 is pretty close to the original tire diameter and the 195/75 is marginally larger; probably not enough to cause serious issues. The larger problem is the 9" drums themseves. If it were me I would upgrade to 10" drums at a minimum and preferably to front disks. The added brake performance is well worth the cost of the upgrade. The stock 9" drums are marginal at best.

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David Kight
'62 Valiant Signet, White
'98 Dodge Dakota
'06 Jeep Liberty

Growing older is unavoidable but growing up is strictly optional.

Huh?! :shrug: That makes no sense. You will not experience brake failure, of all the bizarre claims to find on the internet, by increasing your tire size. There is the question of brake adequacy (9" drums are marginal on this score regardless of tire size), but not of brake failure.
Those are fine on 14 x 4&189;" or 14 x 5&189;" rims, though they are a smidge too wide for best results on the narrower rims. Which width are your rims?

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

The failure that is aluded to could be the bolt for the lower ball joint, on the 9" brakes it is a smaller size than on the 10" drums or the disk brake cars.

The report of ball joint bolts breaking because the car has 9" drums seems to come from nobody besides Rick Ehrenberg.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Thanks for all the responses especially debunking the ball joint breaking myth. I planned to get new drums so I'll upgrade to 10" (finned), I had a 68' Coronet years ago, had 16'' rims on it, forget the tire size and 10" drums front and back and never had a problem. So with the 10" upgrade I'm going to run 195/75/14 on my 63' Dart. Someone asked what the width of my steel rims are, I don't know but they are stock from a 68 or 69 Barracuda, maybe that will answer your question. I really like this size on the car, it raises it up an inch or so so I clear all the concrete stoppers in the parking lots and don't hit my gravel pan anymore. Thanks again guys, this site is great and has been a life saver.
Brian

I was looking into only getting a new spare this week when I discovered that the other four are over stock a size or two according to my door sticker. Odd I thought, since two new ones were added at the garage which did my safety a couple of years ago. Hmmm.... I remember failing a safety check a long time ago with a different car because the tires were over stock- can't win for losing I guess. Dammit ....going back to stock and hopefully gain a better ride/handling and maybe even a couple of MPG.

What? Are you kidding me? Where do you live?

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vm