deedubb

iTrader: (9)

How much width are we talking about between 245 and 255 or in this case 275 and 285. Example: every size you go up, its xxx inches more.

Higgs

iTrader: (2)

The width of the tire, 245, 255, whatever... is a measurement, in mm, from sidewall to sidewall. So, a 255 is 10mm or 1cm wider than a 245, and so on.

25.4mm in an inch, so each "size up" is about .39 inches in width.

The series, or aspect ratio (second number, 35,40,45,50, etc.) refers to the height of the sidewall expressed as a percentage of the tire's width. For example, then, a 275/45/18 would have a taller sidewall than a 275/40/18.

deedubb

iTrader: (9)

That's exactly what I was looking for! Thank you!
So If I went up from a stock 245 to a 275 in the rear, i would be just over an inch wider (or .39's of an inch x 3 = 1.17 inches wider)?

Higgs

iTrader: (2)

Basically, yes. Remember - You will need to choose the correct aspect ratio to keep the overall tire diameter correct, for the sake of the Stability Control system. Example - With the stock 245/45/18 on the front, if you put a 275/35/18 on the back it will be too small of an overall diameter in the back and it'll play hell with the Stability/Traction control... since the rear tires will be completing more revolutions per distance relative to the fronts, it will be interpreted as wheelspin.

Slightly off topic... some 275's may seem wider than others... usually due to having a wider tread with. Type and design of the tire influences this... where a normal passenger car tire may have the section section width of XXX, its tread width may be narrower, for a more tapered in appearance from the back. Typically performance tires are more square shouldered, with the tread with being much closer to the XXX section width. Make sense?

deedubb

iTrader: (9)

That makes sense. As far as total circumference goes, what is the optimal size sidewall height I should use when going to 275's from the stock 245's...40 series? (275/40/18).

Higgs

iTrader: (2)

Yep, you want an overall diameter as close to 26.6" as possible. Depending on tire, a 275/40/18 will be in the right ballpark... somewhere around 26.7" which will be fine.

deedubb

iTrader: (9)

Sweet, thank you much!

y2kfrc

iTrader: (3)

im running 295/35/18 BFG's, i could snap a pic of some ppl would like. They are on widened stockers, and i run 285 i think on my CCWs

Capown

iTrader: (5)

Thats the problem im seeing now with my Stab control keeps poping on once in awhile. 245/40 up front and a 295/35 in the rear.

I would love to see some pics if you don't mind.

y2kfrc

iTrader: (3)

so for the crappy iphone pics

Capown

iTrader: (5)

where did you get your stockers widened at and $$$ I may ship my Team dynamics to them if its decent $$.

onebadcad

iTrader: (1)

Use this calculator to help you with tire sizing:

http://www.1010tires.com/tiresizecalculator.asp

Cts-Voodoo

Y2Kfrc - what are the specs to your rims, and it doesnt look like they stick out, do they? I want to have sex with that rear tire shot lol

y2kfrc

iTrader: (3)

They stick out a VERY little bit!!! and my car is lowered a good amount on coilovers and doesnt rub the tire at all. Now i wouldnt recommend having yoru stockers widened to 10" because of clearance issues with a trailing arm, and the fact that i have to run longer studs and a spacer in the rear. If you go with 9.5" you can fit the same tire and you wont have to clearance much if anything.

as far as widening the wheels talk to your local Discount tire co. my roomate works there and did it for me

tech talk

Try Weldcraftwheels.com; they're in Michigan.

Capown

iTrader: (5)

I run the 295s but they poke maybe a 1/2 inch on a 9" wheel. Ill call discount tomorrow and see what they say thanks.

GhettoTy

iTrader: (2)

I talked to 2 different Discount stores today and neither of them offer that. anyone have an idea on pricing to widen a wheel?

Higgs

iTrader: (2)

I was quoted $250-300 per wheel to have two of my buddy's Vette wheels widened. It wound up being a better deal to just buy a different set of wheels. Probably more worth it with a CTSV since there are so few wheel options, plus the stock ones look pretty good. I can probably dig up the name of the place (in Ohio I think) that quoted me on that. Let me know if you're serious about it. Also not sure how far "inboard" you can go on a V without having clearance issues. Gets a lot more expensive to widen a wheel if they have to cut it apart in two places.

tech talk

Weldcraft; $200/wheel for 1" wider to the inside; just talked to them today.

Tech

67+05caddyV

BTW, That pic of the rear set up is perfect.

I had a recent issue (read curb/guardrail) with the rear letting go on my favorite s-curve off ramp and now want to look into this mod.

So let me know if this is correct for running 295's on rear:

1) Have stock rims widened to 9.5 inches (looks like $200 per)
2) Mount 295's on new rims (recommended tire?, grip vs cost?, aspect ratio if running stock fronts)
3) Get 5mm spacers made (cost estimate & who?)
4) Get longer rear wheel studs (cost & where to buy?)
5) Need to roll fenders??

Also, is running stock fronts with 295 rears make sense handling wise ???
It's my daily driver (except winter). I like hooning around on the on-off ramps , I don't drag or track and occasionally drive two hrs on business - i.e. comfort vs performance?

Great discussion, thanks for the info!
BL