Tires to replace run-flats on 18" R105's?
 

Any suggestions? What size tire can I run? Prefer a shorter side wall nothing too big.

TY

I replaced my run-flats with Goodyear Eagle F1 Allseason a couple of years ago and I have been extremely happy with them.:thumbsup:

http://t3.gstatic.com/images?q=tbn:7...es%2Btread.jpg

What size?

205/45 R17
If you do a Google Image search you'll see them on larger Corvette rims for a size reference.

TIRE SIZE | DIAMETER |
+-----------+-------------------+
| 195/55-15 | 23.44in (595.5mm) |
| 205/40-17 | 23.46in (595.8mm) |
| 215/50-15 | 23.46in (596.0mm) |
| 215/45-16 | 23.62in (599.9mm) |
| 195/50-16 | 23.68in (601.4mm) |
| 185/60-15 | 23.74in (603.0mm) |
| 215/40-17 | 23.77in (603.8mm) |
| 205/55-15 | 23.88in (606.5mm) |
| 215/35-18 | 23.93in (607.7mm) | <--------- Maybe this size
| 175/65-15 | 23.96in (608.5mm) |
| 225/45-16 | 23.97in (608.9mm) |
| 205/50-16 | 24.07in (611.4mm) |
| 225/40-17 | 24.09in (611.8mm) |
| 225/35-18 | 24.20in (614.7mm) | <----------This could work too...pretty wide
| 195/60-15 | 24.21in (615.0mm) |
| 205/45-17 | 24.26in (616.3mm) |
| 215/55-15 | 24.31in (617.5mm) |
| 195/55-16 | 24.44in (620.9mm) |
| 205/40-18 | 24.46in (621.2mm) | <-------Assuming you had these
| 215/50-16 | 24.46in (621.4mm) |
| 185/65-15 | 24.47in (621.5mm) |
| 215/45-17 | 24.62in (625.3mm) |


going to depend on your driving, but for my all seasons i just got to run through winter, they are the Goodyear Eagle GTs... So far theyre great in the noise/comfort/grip/rain categories.... snow will be here shortly i bet

I am assuming I have 205/40-18's on them.

Thanks for your help my man.

A- 225/35-18-Goodyear F1GS-D3:mushy turn-in, great grip, discountinued
B+ 215/40-18-Nitto NeoGen:sharp turn-in, good grip
C- 215/40-18-Hankook K104:constant flats and bubbles
C 205/40-18-Dunlop Run-Flat:sharp turn-in, decent grip, harsh

Other street tires I want to try.
215/40-18- Falken ZIEX ZE912
215/40-18- Hankook Ventus V12 EVO K110

Unfortunately, sticky tires are limited for the 18x7 wheel. Thats why I also got a set of 17 inch wheels to run sticky tires with ie: star specs, XS, R888 (currently)

Just did the same thing this weekend so far so good I put 215/35/18 on the GP rims

My bad I just noticed you got an R56, you can probably fit 225/40-18 and they have all the great tires in that size, like the: XS, Star Specs, RE-11s, R1R, RS-2, and AD08s. But these should not be used in heavy rain, any snow or below 40 degrees though.

So a 225/40/18 would be ok with the R105's? How about a 225/45/18?

I'm running the same 205's in 18's.... I'm getting ready to order 225/35-18's. I chose that size because they're the same size as the stock 205's in 17's.

Right now I'm running 205-40/18's and they're making my speedometer 2-3 mph off. (it shows I'm running slower than what I really am).

The 225's are a hair (like 1/10") shorter which should bring the height perfect for my speedometer plus they'll be a little wider which should look cool. (er)

By the way, I'm running the Yoko S drives.... great tires, relatively inexpensive (133.00), got great reviews, handles well in the dry and rain and lasts a decent amount of time. IMO, best bang for the buck.


Mark

It might? But why?
40 series offers better gearing and better selection (XS, Star Specs, RE-11s, R1R, RS-2, and AD08s)

A 225/40-18 is 25.09" tall.

A 225/45-18 is 25.97" tall.

A 205/45-17 (stock size) is 24.26" tall. If you put your second choice on, you're talking about 1 3/4" taller.... that's ridiculously larger.

Not only kill your gear ratio, give you worse gas mileage but it may cause rubbing issues.


To me, it's important to keep the factory overall diameter because not only will your speedometer be correct but with different height tires, your mpg reading will not be correct.

Mark

yeah a 45 series on an 18" rim would look a little odd. Its a biiig difference, and itll screw up the speedo and probably rub at full lock....I put 205/55/16 on for winter and they rub, because i intended on running a 50 sidewall...

all im saying is try and keep your diameters close like orange is saying

I asked about 225/45/18 because I was trying to get some S-03's (favorite tire) and since they are discontinued the selection is slim. I use to have them on my WRX back in the day with a 225/40/18 on a 18 x 7.5 wheel.

just have to look up the specs for it.... if its much much taller than something like the 24.26" orange posted, you may want to reconsider...different tires of the same size often have much different dimensions, so there is a slim chance that the 45 could work out ok... if they "run small"...and that 'gear ratio' issue....you will notice it.. no fun having your car feel slower :(

Hope this is how you reply, if the R56 is lowered with H&R springs will fit the 225/35R18 tires?

225/40/18

Actually, 225/35/18's are closer to the 205/45/17's original height.


Mark

:nod:

Quote: Originally Posted by TEDIE https://www.northamericanmotoring.co...s/viewpost.gif
Hope this is how you reply, if the R56 is lowered with H&R springs will fit the 225/35R18 tires?

Quote: Originally Posted by orangecrush https://www.northamericanmotoring.co...s/viewpost.gif
Actually, 225/35/18's are closer to the 205/45/17's original height.
Mark

Quote: Originally Posted by iwashmycar https://www.northamericanmotoring.co...s/viewpost.gif
:nod:

If you track like Oxy they have all the track worthy tires available only in 225/40-18 or I'd go with that size despite (O.D.) gearing if I lived in a place with very bad roads like NYC, Phily, or TJ for a more comfortable ride oh and didn't have to carry 4 passengers either.
Otherwise :nod::nod:

Oh, I was doubting Chad's choice but I think most people would want as close to possible the OEM size to maintain performance, gas mileage and mph readings....

Though I run 18's for the street, I use 17's for the track because of your exact reason.... selection and price.

Mark

I wish they made auto-x type tire for 18x7 wheels in 215/40-17.
I too got R98 17s for cheap til I could get some lighter ones, now got TrakLites 2s in 17, but now thinking I want 15s mostly for price, selection and gearing I guess.

I did also until I saw the price differences when going to a set of 18's. I'm running the OZ Ultraleggeras in 18's on the street and have the same wheels in 17's for the track. I choose them only because they weight 14.7lbs. I just mounted a new set of RE11's so I'm set for Roebling in a couple of weeks.


Mark

Looks as though I am going with 225/40/18 Dunlop Star Specs for my 18 x 7 R105's. They do offer RE-11's in that same size as well.