Needing new tires..

I have 165 SR 15 Pirelli P3's on there and they are AT LEAST 20 years old. They certainly don't make tires like that anymore. The tread is awesome there are sidewall cracks from UV and such that I need new tires. I would like 185's. On the drivers side rear no problem but the passenger side rear is too close I think for a 185.

Drivers side maybe has 1" of space, passenger side less than 1/2"

Ideas?

Tire math 101: The difference in width between a new 185 tire and your 165 is 20 mm. So half of this increased width is added to the outside of the existing 165 tire. So a 185 tire is 10mm farther outboard than your 165. 10mm extra width divided by 25.4mm per inch = .393 inches, or a tiny bit more than 3/8 inch. A 185 might just fit!

If you want the tires on both sides to be even, you might consider a thin wheel spacer. I doubt you would notice any handlling difference for a street driven vehicle (but you'll need an alignment).

Give a good eyeball to your clearance when your suspension is fully compressed. Just last weekend I cut a half inch arc off part of one front flare to get needed clearance. Worked good for me.

Doesn't the aspect ratio come into play too --- the old 165's were probably 80 or 75. Where new tires are 70 or 65. I think even 185/70x15 might be hard to come by now days and not sure if 195/65x15 would fit (find some one with an old tire from a Honda Civic or Toyota Corolla for a trial fit).

Ha, I've got new 15 year old Michelin XZX on mine!

Mike,
What size wheel are you running? Are you IRS or swing axle? Discs?
A 185/65/15 will fit a swing axle with 5-1/2 wheels no problem.
If you have an IRS with drums and 5-1/2" wheels no problem.
If you have IRS with disc brakes you'll have to run 4-1/2" wheels to fit.
165/15 are still readily available but you'll appreciate the lower profile and added footprint of a 185/65.

The tires,
http://www.cip1.ca/SearchResults.asp?Cat=1266

The car is swing axle with drums in the back. Wide 5 in the back with steel rim and moon caps I just measured 2 that I took off the car when I had to change them when converting to disc. They are 6.5" rims. WTF, er that means 5.5" inside the flange to flange...

According to the specs the 165's are 6.25" wide and the 185's are 7.4" wide on the rims. Which is over 1" (not sure why this would be the case)

The prices are amazing.

Mike, you are right. Tire math is one thing, and manufacturers specs are something else. Not only does width vary a bit, if you compare various makers diameters (or revs per mile) for identical tire sizes, they are slightly different also. IMHO it is related to tread depth and tread pattern. Don't know exactly what the industry standards are for measurement. Probably why the cops will give you 10% on the speed limit?

By the way and for information only, 20 year tires are an accident waiting to happen, regardless of tread depth. At the 5 year mark, the moisture is gone from the rubber and they internally crack, externally crack or both. In addition, the plies began to separate. I have a friend who is a retired tire engineer and he's the one who told about this little known problem. He won't drive on a tire that is over 5 years old and he's not in the business of selling tires as he's retired and no longer has allegiance to his former employer.

Just picked up a 185/65/15 winter tire at the local garage from his tire dump that is supposed to be picked up for recycling next week. I'll mount it on a spare and check it out...then throw it in the GHIA as a front wheel well tire for windshield washer pressure :)

Larry you are right. I think that hotter and sunnier climes do wear out tires faster. But you are correct. On my dailies the tires rarely last 2 years. On Fern, they were probably close to 25 years old... amazing but I know now, not a good idea. But amazing none the less.

A good write up: http://www.mpt.org/motorweek/goss/2535.shtml

The tire compounds make a difference also it gets me i'll when you get use to abrand and then they change the compound to save cost and stick it to the customer who winds up with a softer compound tire that ware out faster. Tires should have a compound code and a set standard that is inforced by the DOT and understandable by all consummers.

Well this thread behooved me to check my tires. I've had the car all but 6 years so I looked at the code stamps. Suckers are 10 years old, and undoubtedly hard as a rock.
Sooooo....Blackie went for new sneakers today. Never had an alignment before so did that too.
Man, WHAT a difference that made, especially now that the front rims aren't as crooked as Barney Google's eyes. That new rubber rides nice and smooooth, Daddy-O! All ready for Carlisle now!

~WB

Wild Bill,

I'm going to have to do this one of these days too but right now the funds are going into the roadster. What size/brand did you get?

ECB

Buce: I bought a set of Kumho Ecsta's 225/50/15. They got me right in and were done in 1 1/2 hrs.

~WB