Jump to content

Wheel and Tyre Width


TarkMalbot
 Share

Recommended Posts

The good news is the OZ Ultraleggera 18x7.5" are lighter than the standard 17x7" and the Toyo 225/35/18 tyres are just the same weight as the 205/45/17 tyres! This keeps the same rolling diameter and overall the 18" package will be lighter than my current 17" package and it will look good too! 225 width will be ok on a 7.5" rims wont they?

Link to comment
Share on other sites

I think 18s would be a little too large and demand too small a profile. but that's just me :( I liked the photoshop on the previous page.

 

As for unspring weight, yeah maybe a little lol.

 

I liked the idea of the Graphite wheels too for a while but when I see my car with its stainless grille and silver badges and stuff I go back to liking the silver wheels. lol. The missus has some say too when it comes to thigs like this. I have to pass it with her first! There doesn't seem that much point changing from the standard 17" to OZ 17" of similar design just to save weight.

 

On the other hand £1300 is a lot of money just to have an inch bigger rims. lol :lol:

Link to comment
Share on other sites

I am starting to think maybe stick with 17" rims but go to 7.5" wide and increase the width of the tyre. Will still work out lighter than standard, more agressive offset and look different. And I might go back down the graphite route. Not to mention 17" is £500 cheaper than the 18"

 

I used to be indecisive but now I am not sure! :)

Link to comment
Share on other sites

Liking the look of these though:

 

fiveclub-1227016116-210-203-191-30.jpg

 

225/40/18 Wheels are the same weight but the tyre will weight almost 2Kg more.

 

I think 225/35/18 will be too low profile after looking at that photo!

 

Be sure to keep the revolutions per mile within 5% of the OEM wheels/ tyres.

Link to comment
Share on other sites

Going back down the 17" route now!

 

235/40/17 on 8" rim would keep the same diameter as the standard 205/40/17 although I think it is a bit wide for what I need!

 

The 225 options on a 7.5" rim with the tyres I want (Toyo T1-R) is 225/45/17 which will increase the profile from standard and the diameter by 0.6". That shouldn't make too much difference I guess. They don't seem to have a 225/40/17?

 

Maybe the most sensible option would be to go 7.5" rim with 215/40/17 tyres although this will reduce profile, the diameter by 0.5" and therfore more importantly show the gap between the wheel and arches! lol.

 

Someone tell me to stop being such a fanny and just buy some!

Link to comment
Share on other sites

Going back down the 17" route now!

 

235/40/17 on 8" rim would keep the same diameter as the standard 205/40/17 although I think it is a bit wide for what I need!

 

The 225 options on a 7.5" rim with the tyres I want (Toyo T1-R) is 225/45/17 which will increase the profile from standard and the diameter by 0.6". That shouldn't make too much difference I guess. They don't seem to have a 225/40/17?

 

Maybe the most sensible option would be to go 7.5" rim with 215/40/17 tyres although this will reduce profile, the diameter by 0.5" and therfore more importantly show the gap between the wheel and arches! lol.

 

Someone tell me to stop being such a fanny and just buy some!

 

Stop being such a fanny and just buy some ;)

Link to comment
Share on other sites

Going back down the 17" route now!

 

235/40/17 on 8" rim would keep the same diameter as the standard 205/40/17 although I think it is a bit wide for what I need!

 

The 225 options on a 7.5" rim with the tyres I want (Toyo T1-R) is 225/45/17 which will increase the profile from standard and the diameter by 0.6". That shouldn't make too much difference I guess. They don't seem to have a 225/40/17?

 

Maybe the most sensible option would be to go 7.5" rim with 215/40/17 tyres although this will reduce profile, the diameter by 0.5" and therfore more importantly show the gap between the wheel and arches! lol.

 

Someone tell me to stop being such a fanny and just buy some!

 

Stop being such a fanny and just buy some :)

 

PMSL. I guess I asked for that. Litterly.

Link to comment
Share on other sites

  • 2 weeks later...

Managed to order my new wheels last week. I am going for 17" by 8" wide with 235/40/17 Toyo T1-R Tyres. Offset of 48mm. These will be the same diameter as the standard wheels but with the extra width.

 

I spent weeks deciding what wheels to get and what size and eventually decided on these. What a nightmare they were to get hold of. Don't pay any attention to any prices online as I phone up everywhere and the UK importer has stopped bringing them in so no-one seems ot have any in stock. They can import them but with the current exchange rates expect tp pay 30% more than they used to be! And when speaking to idiots it gets very frustrating when they can not write down simple things such os the rim width or diameter...

 

"Do you have 17"x8" PCD114.3 ET48 Please?"

 

"We dont have them but We could import them. Just one moment I will check our supplier for you. (puts me on hold for 5 mins)... Yes we have the 17" wheel"

 

"Is that in the 8" Width?"

 

"I will just check that for you. (another 5 mins on hold) Yes we have 18"x8""

 

"I asked for 17" x 8". I'm not getting anywhere here am I? Bye!"

 

I eventually managed to find somewhere in the UK that had them in stock! Still a little more money that I had first though but I should have them in a few days. William Murphy of PerformanceAlloys.com was very helpful and even a MX-5 fan himself!

 

Looking forward to getting them on the car friday hopefully.

 

Just two questions. Should I be running the same tyre pressure of standard ie 29psi and when it comes to geometry would you set it any differently to a car running standard wheels?

Thanks.

Link to comment
Share on other sites

Start with the OEM pressure and monitor the wear then adjust accordingly. If you have issues with tram-lining post here again and we will deal with that then.

 

As for Geometric changes, yes.....

 

1: The wider tyre will generate more rolling resistance so the Toe position may need to be changed.

2: The off-set may need a camber change.

3: The cars weight spread over a wider contact patch may need the castor extended to add feel.

 

Over than that everything's the same :rolleyes:

 

Off-topic do the wheels need spigot rings?

Link to comment
Share on other sites

I was told the wheels come with everything I need to fit them to my car so I will let you know when they arrive. I have had mixed opinions about clearence though. A lot of people say they have no issues with the 235 width but others say they need to roll the arches a few mm. I hope that depends on tyres as the guys with no trouble said runninf the Toyos were fine! I don't want to have to run a silly chamber so they don't touch!

Link to comment
Share on other sites

I was told the wheels come with everything I need to fit them to my car so I will let you know when they arrive. I have had mixed opinions about clearence though. A lot of people say they have no issues with the 235 width but others say they need to roll the arches a few mm. I hope that depends on tyres as the guys with no trouble said runninf the Toyos were fine! I don't want to have to run a silly chamber so they don't touch!

 

We can roll the arches for £75+ per axle if needs be.

Link to comment
Share on other sites

Most say I wont and that you only need to roll them 2mm or so if your going to 245 width. I should know by this weekend anyway. Even if they did need rolling It is a straight motorway journey down to yours so should be too much of a problem (I Hope!)

 

Well like i say it would need to be booked so i'll leave this to you......

 

Since you now have this glorious modified car are you ready to use our NC fast road setup :crying_anim:

Link to comment
Share on other sites

Fast road comes in different formulas depending on the cars modifications and intended use. There tends to be two intentions from the customers.

 

1: Tyre preservation

2: Performance

 

Problem is performance is not concerned with tyre life but!!..... there is a gap in between but it needs to be found, fortunately our software can imply dynamics helping us find the best positions.

Link to comment
Share on other sites

Sounds interesting. I would like a fast road set-up but would like to have my tyres wear equally if possible. I guess it is the chamber that causes wear on the inner edges of the tyre.

 

Oh and the wheels are here and fitted. Love the looks and the wider stance. Fill the arches well and no rubbing so far. They even feel more comfortable that before even though the profile is just the same. Is this to do with the extra width or just different tyre manufacturers?

 

The same Diameter but extra width:

 

IMG_0365.jpg

 

More width:

 

IMG_0360.jpg

 

Standard wheels 17"x7" with 205/45/17 tyres weighed in at 16.7 Kg each:

 

IMG_0357.jpg

 

The Ultraleggera wheels 17"x8" with 235/40/17 tyres weighed in at 18.0 Kg each:

 

IMG_0358.jpg

 

To be honest I am happy enough with this as I didn't expect to have an inch wider rim and 20mm wider tyres and actually save weight anyway. I though it could be up to an extra 2 Kg more so 1.3Kg is better than expected. I don't think the extra weight will make much difference anyway.

 

I have some photos but they aren't very good. The car needs a wash, the bakes are rusty from sitting for 3 weeks and the photos were taken just after fitting so the suspension is sitting too high and gives the impression they are wider than the arches. It is looking much better now I have had a good drive and things have settled in and the brakes are clean.

 

23012009369.jpg

 

24012009381.jpg

 

24012009382.jpg

 

24012009383.jpg

Link to comment
Share on other sites

Nice looking wheels although staying on top of the cleaning will be a challenge.

 

The extra width/ camber/ off-set and advancing the handling without adverse tyre wear will need careful consideration once the car's on the rig, nevertheless it will be just fine.

 

As for the "comfort feel", i would say it's because of the better make of tyre.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...