Hello folks,

its about time for me to shop for new tires for my JCW Wheels.

They come with 205/40/18

Unfortunatly, this is such a special size that its only available at costy prices.
What are my other size options? what are the disadvantages if I change tire size from the actual one recommended.. for exmaple:

225/35/18 or 215/35/18 or 215/45/18 ... these sizes are more common..

suggestions?

 

215/40-18 & 225/35 are closest to the stock size.
should find a decent selection in those sizes.

 

Here is some size comparisons for your options:

Tread Aspect Wheel Tire Tread Sidewall Dia. Comments
Width Ratio Dia. Dia. Width Height % Off
205 / 40 - 18 = 24.46 8.07 3.23 0.0 JCW Option
215 / 40 - 18 = 24.77 8.46 3.39 1.3
215 / 35 - 18 = 23.93 8.46 2.96 -2.1
225 / 35 - 18 = 24.20 8.86 3.10 -1.0
225 / 40 - 18 = 25.09 8.86 3.54 2.6

I would suggest 215/35x18. If you go with 225/35x18 you need to be concerned with wheel offset to eliminate rubbing.

 

There is one thing that I should mention, my car is lowered by eibach springs, so I dont know quimni what I could do in terms of offset. But it is true I should consider the offset, because with the 205/40/18 that i have on now, and the rear tires are so close to the rear plastic fender (sideways), and about 10% of tire covered by fender.
I am planning on Goodyear or Michelin
Michelin:
225/35/18 - I got one choice
225/40/18 - there are 6 choices

Goodyear
225/35/18 - again one choice only
225/40/18 - 2 choices

all other combinations are not possible..

 

did you come to a conclusion at last?

 

I'm currently running 215/35-R18 on my R105s... lowered on JCW springs, so not much lower. But the smaller tires lower me about 1/4", so I definitely scrape more than with the orig. size tires. I will probably try 215/40 next time... but either should work in most cases (as was mentioned).

 

i lowered my car with the M7 Springs ~ :(

 

Not possible?

Why Goodyear or Michelin?

215/35-18 is the size of choice
Tirerack.com shows 16 tires that match that size
Max Performance, UHP and UHP All Season tires to choose from.
None of the 16 are made by Goodyear or Michelin.

 

Then am I right in thinking if I have stock suspension and I upgrade to 18x7.5 wheels with 215/35-18 tires I'll both:

1. eliminate wheel gap and
2. not rub?

 

You won't eliminate wheel gap because 215/35 tires on 18" wheels will have a lower overall diameter than any stock wheel/tire combination:

215/35-18 = 23.93in (607.7mm)
175/65-15 = 23.96in (608.5mm)
205/45-17 = 24.26in (616.3mm)
195/55-16 = 24.44in (620.9mm)

 

As wheel-diameter grows, sidewalls shrink. If the sidewalls didn't shrink, the overall circumference would grow and wreak havoc on your instruments. The only way to get rid of the gap is to lower the car.

 

I've got a set of 18" JCW R95's (double star spoke, blah blah's). I want to save the run-flats for when I sell the car and I want to get a set of performance tires for the canyons and daily driving in Los Angeles. I just want a bit more edge to the handling and maybe make it a more comfortable ride.

I've read the info here, but it's still a bit complex for me. I heard from a few people the Nitto Neogen's were good tires for the price.

Which size/brand/model would you guys suggest based on my preference?

 

I just installed the JCW R105 with Yokohama S-lites. What a change from these horrible heavy OEM Dunlop run-flats with r104 Crown Spokes. The ride is a lot smother on the 18" then it was on the 17".

 

Try searching tirerack for
215/40-18
Ultra High Perf Summer tires-
Yokohama S.Drive $139 each 300 treadwear, good handling and good comfort.

For more handling but not as comfortable
BF Goodrich g-Force T/A KDW2 $146 each 300 treadwear
Yokohama Parada Spec2 $124 each 300 treadwear

Without worrying about price-
For good balance of handling with comfort, check out
In Ultra HP All Season tires
Pirelli PZero Nero M+S $149 each 400 treadwear
test result-
http://www.tirerack.com/tires/tests/...ay.jsp?ttid=87

 

what size tires did you go with on the R105's?

 

Why the 215/40-18? Tire sizes are Chinese to me so any clarification/explanation would be greatly absorbed by my brain...

What do you think about the Nitto Neo Gen's? They've been recommended to me.

Between the Yokohama S.Drive, Pirelli PZero Nero M+S, and the Nitto Neo Gen's, which gives the best balance of handling & comfort?

I read the test of the PZero Nero's. Looks nice. And, I can kinda justify the higher price since it's a 400 treadwear, right? ;-)

 

Yokohama S-lites?
see
http://www.tirerack.com/tires/tires....eModel=S.drive

You can also check out this UHP All Season tire-
http://www.tirerack.com/tires/tires....Model=AVID+W4S
In 215/40-18 $123 each 400 treadwear
Tests-
http://www.tirerack.com/tires/tests/...Model=AVID+W4S

 

I am very happy with 215/40x18 size tires on my 18" GP Wheels.
215 is the width of the tire in millimeters. The 215 is wider then the stock tire (probably a 205 in your case).
40 is the series of the tire and defines the tire sidewall height. The sidewall height is tire width times the series divided by 100. 215*40/100=86mm. A 18 is the wheel diameter.

A 215/40 will give you a much smoother ride than the stock runflats. If your car is stock ride height, the 215/40x18 will fit with no rubbing issues.

 

Good to know about the smoother ride, but does this come at a cost to handling? The run-flats are horrible, IMHO. I have a set of Megan coilovers I am waiting to put on. If I've lowered the car, will I have rubbing issues with the 215/40x18?

I'm also contemplating selling the R95 double-star spoke wheels with the runflats and buying some other 17" or 18"s. If I went to a 17" would my cornering suffer compared to the 18"s?

 

After a lot of research I went with 205/40/18. Since I didn't install the steering stops I decided not to go with 215/40/18. I was planning to lower the car to reduce the wheel gap but with the black r105s I don't think i'll need to do it, it just looks so nice. Anyway I am really happy with this set up. BTW the r105 are less than 1 lbs heavier then r104 Crown spokes i had. The Yokos are a lot less heavier than Dunlop RFs.

 

My 215/40x18 Toyo T1R tires ride smoother, are quieter, and handle better than the stock 205/40x18 runflats.
Rubbing will depend on the offset of the wheels that you use.
Based on the Grassroots Motorsports article, the handling might be better with 17" instead of 18". But 18" sure fills the wheel well nicely, especially when lowered.

 

When I do get my car... I was thinking about going with the Toyo's T1R with the Team Dynamics Pro Race 1's. How many miles do you have on the tires? I heard the treadwear is just so so (approx. 20K life span) vs. something like Michelin's.

 

I only have 1k on the T1R tires. For me 20k would be great. I only got 20k out of the stock runflats and they were totally worn out. I would expect to get about 15k out of the T1Rs.

 

Thanks to everyone's suggestions. This thread was really helpful. I ended up getting lost in reviews on TireRack.com for quite a while.

Props to minihune (my tire guy ordered the Yoko S.drive's for me today).

Getting installed tomorrow :-)

 

Compared to the OEM runflats, the 215/40/18 Yoko S.drive's are very quiet and much more forgiving on the potholes in L.A. It's strange to hear the engine with so much less tires noise...plus not feeling every road imperfection is grand.

Much, much better. Wish I had done this eons ago...

Anyone comment on more suspension upgrades worth of making a better, more comfortable ride? (coilovers, maybe?)