A few wagon specific Impala SS tire questions- Please chime in!

[NotNSUV]

In 2007, I purchased a 1995 Roadmaster wagon, removed the stock wheels and tires and replaced them with Impala SS wheels and Impala SS OEM, 255/50-17tires. After the tires wore out I went back to the stock Roadmaster wheels and tires that came with the car since they were in good shape. The time has now come for new tires and I have decided I want to go back to the Impala SS wheels. But alas, these days its slim pickings for the 255/50-17 tire size and I am not wild about any of the choices. I am hoping I can put a different size tire on the Impala SS wheels to broaden my choices, but the options are unclear to me. I have searched these forums and could not come up with the information I seek. I have a few questions and I hope some of you can steer me in the right direction. I should mention that I don’t want smaller tires in the front- I want to keep it simple with all 4 tires being the same size.

1) What size(s) tire will fit the Impala SS wheel without interference from the wheel well or anything else in the undercarriage? What is the best fit other than the 255/50-17 size?

2) When I had the 255/50-17’s on the car, I noticed the outside diameter was a bit (I am guessing about an inch) smaller than the stock wheels. To my eye, it looked as if a larger diameter tire would fill the wheel well more and look better. When I read about tire sizing and I found that the aspect ratio is not a clear-cut number, but rather, a relationship between the tread width and sidewall height. I don’t know what tire size I to put on my wheels in order to retain the stock Roadmaster outside diameter size, or at least to come close to it. What size(s) tire would have the larger outside diameter I seek, and most importantly, would they fit without interference or modifications?

3) When I previously had the 255/50-17 tires on the car my front passenger tire would hit the front stabilizer when I turned to wheel hard to the left. This eventually wore the tire where the tread met the inside sidewall. Someone once told me there is some sort of inexpensive “stop” I can clamp onto the suspension to keep this from happening. I realize I would lose some of my turning radius, but this seems like a fair tradeoff. Does anyone know what this item is called, where I would attach it and where I can get it?

4) Is there a decent website to get the information I seek?

I would appreciate any advice. Thanks for your help!

[1slow96]

Regarding your question about "steering-stops", I addressed this issue by drilling/tapping a hole (1/4 x 20) on the stop on the opposite side from the tire with the clearance issue. This will be more obvious once you get under the car,supported by jackstands. After finding an appropriate stainless screw (oval-head phillips) it's only a matter of adding enough small washers until the tire just barely touches. The difference in turning radius is minimal,and the sharpest turns tend to be right turns anyway.

[1slow96]

FYI a 255/60-17 has a sidewall exactly 1" taller than the 255/50-17,and basically the same width.http://www.discounttiredirect.com/di...foTireMath.jsp

[Marky Dissod]

1.
Best fit really doesn't apply.

255/50R17 (27.03") OEM for 94-96 B-sedans with WX3 or WX8
(doubt this fits in the wagon's spare wheel well?)

225/70R15 (27.40") OEM for 91-96 1A2 Special Service Wagon, and 91-96 B-sedans with L99 4.3L V8

215/75R15 (27.69") OEM for 91-93 9C6 B-sedans - Taxis - with LB4 4.3L V6

235/70R15 (27.95") OEM for 91-96 B- & D- sedans with LT1, OEM for 91-96 B-wagons with V92

225/75R15 (28.28") OEM for 91-96 B-wagons with 2.56

FWIW,

Originally Posted by Marky Dissod

235/7515s - 28.87" - were ordered by mistake for Stuart's Taxi in Westbury, Long Island. He was so miserly, he didn't bother correcting the mistake … which, as it turned out, didn't need correcting.

Despite worn shock dampers and saggy springs (said he was cheap), I once put 10 college girls - 3 in back, 4 in between, 3 up front with me - in a 95 wagon going from CW Post to the Nassau Colosseum.

How I drove back then (worth the tip), of course I bottomed it, if only just. I [was ordered to] never put that many people in a wagon again.

Other drivers regularly put 6 or 7 riders in their wagons wearing 235/75R15 (28.87"), and we all of course would put 5 riders plus luggage jammed to capacity from Westbury to JFK or La Guardia (20 mile drives).

The only MILD rubs were when the wagons were fully loaded, and that's only because the owner was too cheap to buy stiffer/taller springs.

I'll grant that GM never spec'd 235/75R15. I'll grant the look was a bit off - not that anyone cared.

Doesn't change the fact that 235/75R15 (28.87") work just fine with Caprice-spec springs.
Too bad 255/70R15 (29.05") won't fit in the wagon's spare wheelwell.

If you're riding 'lower than Caprice', 235/75R15 would be a problem, sure.

From my spotty memory, I remember that going taller than 29.5" required custom-individualized rear control arm geometry, taller springs, and the inclusion of every 'optional' cushion/seat between the springs and their contact points.

2.
With 17" wheels, you can choose any tire 235-wide or wider, until the sidewalls scrape against the wagon's inner wheel wells. I think that the upper limit, without modifying the inner wheel wells, is 275-wide, but some wagons are not as 'consistent' as others.

3.
Between 27" & 29" tall, and between 235mm & 275mm wide contact patches, you have a considerable number of tire sizes to choose from, even if you limit yourself to H-speed-rated tires.
Do NOT settle for less than T-speed-rated tires for our cars, except for winter tires.

[KW Baraka]

Originally Posted by NotNSUV

[FONT=Arial].....When I previously had the 255/50-17 tires on the car my front passenger tire would hit the front stabilizer when I turned to wheel hard to the left......

Well.....pretty much every B-body is gonna get some rub with 255mm tires when you turn it to full lock. But.....since the sway bar is smooth, I'm gonna say that your premature wear on your tires was due to lack of....or a bad alignment.

That said.....you can always go with a 235/70-17 tires on the stock wheels......it may look like crap, but it'll fit.

My personal preference would be to go with stock height Impala SS springs with 255/50's (Kumho ASX from Tire Rack http://www.tirerack.com/tires/TireSe...50&diameter=17 ).

Or....you can go with your current springs with 255/60's.....but those would all be SUV tires http://www.tirerack.com/tires/TireSe...60&diameter=17 .....

Good luck!

KW

[NotNSUV]

Thanks for the responses so far.

[jayoldschool]

While the "best" wagon tire is 255 55 17 ($$$ and not many choices), lots of us wagon guys run 235 55 17s. They are a good fit on the SS wheel, don't rub, and are ridiculously cheap as they are factory tires on Mustangs and Crown Vics. Yes, they are a little shorter than the stock tire, but work without any issue.

[NotNSUV]

Originally Posted by jayoldschool

While the "best" wagon tire is 255 55 17 ($$$ and not many choices), lots of us wagon guys run 235 55 17s. They are a good fit on the SS wheel, don't rub, and are ridiculously cheap as they are factory tires on Mustangs and Crown Vics. Yes, they are a little shorter than the stock tire, but work without any issue.

If I understand correctly, I reach the following conclusions using the tire size calculator in the link that 1slow96 was kind enough to provide:

My current OEM 225/75-R15's have an overall diameter of 28.29".
My previous 255/50-R17's have an overall diameter of 27.04".
The 235/55-R17's you suggest have an overall diameter of 27.11".

I like the idea of the 235/55-R17's. The major difference from the 255/50-R17's seems to be the width is .79" less. I like the idea that they won't rub at all, relieving me of needing a stop.They are stiill smaller than I prefer, but I must admit they look OK in your pictures. What kind of tires are in the pictures?

[jayoldschool]

Michelin Pilot Sport AS, replaced by Goodyears, now wearing Pirellis.

[NotNSUV]

Thanks everyone!