cpaxson

I know, I know.... tire questions abound. Normally I wouldn't even consider this but we're talking about free tires here.....
I have a 2001 convertible, recently brought. It is one owner, very low miles with thin spoke polished alumium wheels and mostly its been sitting around on it's original rubber the last few years.
Because of obvious flat spots, before I brought the car, the dealer replaced the OEM front run flats with P245/45 - 17 non run flats. The rear run flats seemed a bit better so they weren't changed. But, IMHO, while the tread looks good, face it, these are 12 year old tires and as I actually drive this thing and plan on doing some southern road trips during the next few months, I don't trust them. Also, I don't like the idea of running non run flats with run flats... maybe not a huge problem but it can't be the ideal handling combination. The logical thing to do is replace the rears with the same Michelin Pilot Sports as the front except in 275/40 -18. However, someone had offered me a brand new pair of Michelin Pilot Sports in 295/35 - 18. Again, rear wheels are OEM polished alumium 18X9.5.

According to the table range, then should work (largest size for 9.5" wheels) but again, I'm skeptical. Is anyone running 295 on OEM 2001 rear wheels? I don't want speculation or "I heard" or "I think." It's not a money issue, I'll get the 275's if I have to but after all these are free which is about a $600 gift so if they'll work without screwing up the car or the handling, or the speedometer or whatever, I'll give them a try.

MOre knowledgeable opinions than mine are most welcome and thanks for putting up with the question.

Charles

dblerman

Will they mount on a 9.5" rim? Yes. Would I personally put them on a 9.5" rim? No. Minimum recommended width for that tire according to the manufacturer is 10".
Plus the OD is only .4" bigger than the front and you may run into AH/TC issues running that combination. Personally, I would pass....Or take the free tires, sell them, and use the money to buy tires that would fit better.

B747VET

Personally, I think that is a bridge too far. I agree with you also that I would never mix run flats with non-run flats.

Now that I actually have experienced non-run flats, I would never again even consider run flats on my C5.

Further, If money is really not a huge impediment, I would only say that you might want to consider jumping to an 18/19 combo. That also makes a huge difference in both handling and ride.

Good luck...

Ron Dittmer

If you are a "cruiser" like me, never planning to compete, I strongly suggest you get a road-friendly wheel alignment by a performance shop because any new front tires will be trashed in the first 15,000 miles. I learned that with two of my C5s that I kept a while.

The factory alignment has the wheels tipped inward for better cornering. But it makes the inside of the tires wear very quickly.

FWIW: I replaced my stock tires on my 2003 A/E Corvette with non-run flat Sumitomo HTR Z IIIs The First Ones Listed Here. For $552 and a great ride, they can't be beat for cruising. I now have 13,000 miles on these tires with a street friendly alignment and these tires are still great. I carry a tire repair kit, one much better than the kit that comes with a Z06.

These Sumitomo HTR-Z-III Tires



This Very Compact Tire Repair Kit Bought From Walmart 3 Years Ago

DBLTRGR

I have the inside tire wear problem on my C5 and it's ruined two sets of tires. I've had it aligned twice to try to solve the problem. Do you have the specs from your last alignment specifying what the settings should be? I don't have a Corvette performance shop anywhere near me, but maybe a good alignment shop could do it.

Ron Dittmer

Here are the specs the shop aligned to according to the receipt. The shop does many Corvettes for both on-track and on-street. People go there all the time to get both done just before and again, just after competition.

For 2003 Corvette convertible with Mag Ride

Camber
LF = +1/8 degrees
RF = -1/4 degrees

Caster
LF = +7&3/8 degrees
RF = +7&either 3/8 or 5/8 degrees
(I can't read the one number well, it's either 3/8 or 5/8, but I favor 5/8)

Toe = 1/16"

For the record, this is the shop. You could call and ask them too.
Hartman Bee-Line Services
212 West Chicago Street, Elgin, IL 60123
Phone: (847) 695-7755

I hope this helps.

Vetteman Jack

For a stock size rear wheel, I would just stick with the stock size tires.

DBLTRGR

Ron, thank you! That does help.

Ron Dittmer

You are very welcome!

cpaxson

Thank you all, I think I'll stick with stock. The 18/19 arrangement is something I've considered but nothing is kicking me in the backside to run right out and do it. Maybe next year.

Ron, would those alignment specs work for a 2001 convertible? Meaning, I guess across the C5 line or at least 2001-2004?

leadfoot4

Are you SERIOUS????

Negative camber on one side of the car, which by the way, is the STOCK setting, and positive camber on the other?




To the OP, if you don't mind a slight loss in cornering power, looking for better tire wear, set the camber on BOTH sides at "zero", and the caster at 7.4* on the RF, and 7.0* on the LF. The factory call out for caster is 6.4*-7.4*, but most people prefer a little "lead" on the RF, so the car tracks straight on crowned roads.

Ron Dittmer

Logic says it is the same for all coupes and convertibles, but you never know. I would call Hart-man Bee Line and ask them. Say a Corvette forum member near them recommended you give them a call with your question. Also, if you could, please confirm my 3 or 5. I'd like to clarify that.

Anyone living near Elgin, IL looking for a good Corvette alignment shop, I do highly recommend Hart-man Bee Line.

Ron Dittmer

Alignment shops compensate for a median slope in roads, the slope for water run-off.

Another shop (heavy vehicle specialty) that did an alignment for my motor home had the same story with negative numbers. When I first saw it many years ago, I too thought something was wrong, but no, no, it's good practice to consider the water run-off slope.

leadfoot4

Yes, they do, however the CASTER is the setting that is adjusted to compensate for road crown.

Ron Dittmer

I don't know what else to say other than I have to trust that these two shops know what they are doing, and that my motor home and Corvette tires all wear evenly.

Admittedly, the numbers mean nothing to me. They could say 100 degrees and I'd say "Okay". I never "got into" alignments and what all the jargon means.

corvettebob1

Leadfoot4 is correct about using caster for road crown correction, however lazy alignment tech's will and often do use camber.
What the h*ll the owner won't know the difference as long as it dosen't pull and the steering wheel is straight across it'll go down the road.