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Whats the correct tyres
- Thread starter Dougs260z
- Start date
toopy
Club Member
Well the standard tyre would be 195 70/14 so 205 60/15 on your Rotas is as near as dammit to the original spec
see here https://tiresize.com/comparison/
see here https://tiresize.com/comparison/
205mm is 8" so should be ok?
However it's not as simple as that is it?
The old 175 tyres on a 240 would fit squarely on a 7" rim and they were 4.5"
However it's not as simple as that is it?
The old 175 tyres on a 240 would fit squarely on a 7" rim and they were 4.5"
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Dougs260z
Club Member
Am I correct however that the Toyo R888r's have a hard shoulder and therefore using 225/??R15's would be a better fit on my 15x8's ET0 but this will increase the overall/outer radius as the shoulder sits taller, therefore 225/55r15 would be a better fit.
Can you confirm that this would fit without fender flares, but I assume this is the maximum.
Please note the colour for alloys is black on black, and they came the other day and the outer black is a gunmetal high gloss with the inner being a matt gloss and they look absolutely stunning, no photos can do it justice. Being 15" and black they perhaps do not look too out of keeping with the car, not to bling until you get up close. I uploaded a short movie of my alloys,
The original colour of car is Met Blue and is in the mechanics garage to eventually be turned back to blue.
Can you confirm that this would fit without fender flares, but I assume this is the maximum.
Please note the colour for alloys is black on black, and they came the other day and the outer black is a gunmetal high gloss with the inner being a matt gloss and they look absolutely stunning, no photos can do it justice. Being 15" and black they perhaps do not look too out of keeping with the car, not to bling until you get up close. I uploaded a short movie of my alloys,
The original colour of car is Met Blue and is in the mechanics garage to eventually be turned back to blue.
toopy
Club Member
225/55 15 is, apart from the obvious width increase, an exact match for a 195/70 14 original spec tyre as far as the circumference is concerned
Plenty of people run 225 tyres with no issues, but tires by different manufacturers can have squarer or rounder outer edges, which can make a difference when it comes to suspension or spoiler clearance.
A tyre will always sit slightly proud of the rim, unless its one of those stupid looking over stretched jobbies! hate those
has the car been lowered and if so how?
If its on standard struts but lowered 2" max then your likely be fine, if its on coil overs and slammed and the arches have not been 'chopped' then almost definitely no
Plenty of people run 225 tyres with no issues, but tires by different manufacturers can have squarer or rounder outer edges, which can make a difference when it comes to suspension or spoiler clearance.
A tyre will always sit slightly proud of the rim, unless its one of those stupid looking over stretched jobbies! hate those
has the car been lowered and if so how?
If its on standard struts but lowered 2" max then your likely be fine, if its on coil overs and slammed and the arches have not been 'chopped' then almost definitely no
toopy
Club Member
And that guy in the video is talking C*%P fitting a wider tyre with the same profile/ratio is always going to be taller, the ratio measurement 50, 55, 60 or whatever, is the percentage of the width,
so a 225/55 15 is taller than 225/40 15 because the height to width ratio is 55% not 40% for the same width, hope that makes sense
so a 225/55 15 is taller than 225/40 15 because the height to width ratio is 55% not 40% for the same width, hope that makes sense
Dougs260z
Club Member
Thanks for your response & please correct me if I am wrong.
Alloys at 15'x8'= 381mm x 203.2mm however alloys are measures from the inside face of outer rim of alloy.
on the otherside
225 x 55 r15 the 55 is 55%of the width at 225mm and the 225mm is measured to the outer face of tyre (the overall) not the inside face of inner rim of alloy. The rim is approx 5mm + perhaps 5mm tyre overhang both sides so, 203.2,mm + 2x5 + 2x5 = 223.2mm ish i.e. 225mm
Overall diameter match to original, thanks to Toopy
195x70x14 = 355.6 + 136.5 + 136.5 = 628.6mm
225 x 55 r15 = 381 + 123.7 + 123.7 = 628.4mm (this may hit arches)
for a summary you need a 9" tyre for an 8" alloy.
http://www.tyresizecalculator.com/tyre-wheel-calculators/tyre-size-for-rim-size-width-calculator
Should i use 205x55x15 to the front and 225x50x15 to the rear? Car is 260z 2+2 and is lowered.
15' = 381+112.7+112.7 = 606.5 fronts 205x55x15
15' = 381+112.5+112.5 = 606 rear 225x50x15
or
15' = 381+102.5+102.5 = 586 fronts 205x50x15
15' = 381+101.2+101.2 = 583.5 rear 225x45x15
Obviously this will have an implication on gearing and speedo.
Alloys at 15'x8'= 381mm x 203.2mm however alloys are measures from the inside face of outer rim of alloy.
on the otherside
225 x 55 r15 the 55 is 55%of the width at 225mm and the 225mm is measured to the outer face of tyre (the overall) not the inside face of inner rim of alloy. The rim is approx 5mm + perhaps 5mm tyre overhang both sides so, 203.2,mm + 2x5 + 2x5 = 223.2mm ish i.e. 225mm
Overall diameter match to original, thanks to Toopy
195x70x14 = 355.6 + 136.5 + 136.5 = 628.6mm
225 x 55 r15 = 381 + 123.7 + 123.7 = 628.4mm (this may hit arches)
for a summary you need a 9" tyre for an 8" alloy.
http://www.tyresizecalculator.com/tyre-wheel-calculators/tyre-size-for-rim-size-width-calculator
Should i use 205x55x15 to the front and 225x50x15 to the rear? Car is 260z 2+2 and is lowered.
15' = 381+112.7+112.7 = 606.5 fronts 205x55x15
15' = 381+112.5+112.5 = 606 rear 225x50x15
or
15' = 381+102.5+102.5 = 586 fronts 205x50x15
15' = 381+101.2+101.2 = 583.5 rear 225x45x15
Obviously this will have an implication on gearing and speedo.
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toopy
Club Member
That's all a bit intense, I think your over complicating it, wheel and tyre calculators are useful, especially for matching the new size as close as possible to the original circumference, so as to keep your gearing and speedo as accurate as possible.
However in the real world, people have 205 tyres on 8" rims with no issues whatsoever and so and so on, an unrecommended (according to the calculator) slightly different ratio tyre because thats what they prefer, even though the speedo maybe 3mph out, but if it doesnt hit the arches, who really cares.
Pays your money and makes your choice (armed with suitable info, of course!)
However in the real world, people have 205 tyres on 8" rims with no issues whatsoever and so and so on, an unrecommended (according to the calculator) slightly different ratio tyre because thats what they prefer, even though the speedo maybe 3mph out, but if it doesnt hit the arches, who really cares.
Pays your money and makes your choice (armed with suitable info, of course!)
Dougs260z
Club Member
Yes you are correct Toopy, I was getting a little over eager. Perhaps some people so not realize that alloy width and tyre width are not the same thing, though.
What has become apparent is the lack of tyre choice in these sizes.
I have chosen and purchased Yokohama A048 225 50 r15 for my Rota Kysura 15x8, black on black and perhaps walked into another subject regarding tyres.
I accept that the gearing and speedo might be 3% out but that is well within the legal 5% for MOT'd cars as I understand it, added to this I might get mine registered as a heritage car and therefore no need for a MOT this might be myself just getting a little anxious over nothing.
I'll put winter tyres on the slot mags.
What has become apparent is the lack of tyre choice in these sizes.
I have chosen and purchased Yokohama A048 225 50 r15 for my Rota Kysura 15x8, black on black and perhaps walked into another subject regarding tyres.
I accept that the gearing and speedo might be 3% out but that is well within the legal 5% for MOT'd cars as I understand it, added to this I might get mine registered as a heritage car and therefore no need for a MOT this might be myself just getting a little anxious over nothing.
I'll put winter tyres on the slot mags.
Alphabettispaghetti
Club Member
If you're struggling, imagine getting rubber for 14" wheels.
toopy
Club Member
Its for that exact reason I went for 16" wheels (not yet fitted) I would of been happy with 15" but decent tyre choice is quite limited!
I should imagine on a classic/historic/vintage vehicle this would only ever be an advisory not a fail, if they noticed at all!!
A048 are really a compromise tyre for the road - they are a good tyre for trackdays and getting to and from circuits.
I found that they tram-lined and I wouldn't be happy in heavy rain with them so I'd stop until it was over.
Oh well it's your choice but it seems strange to discuss tyre sizes etc for a long time and then buy track oriented tyres for the road.
I do realise that they are fitted to some cars from new e.g. Lotus I think.
I found that they tram-lined and I wouldn't be happy in heavy rain with them so I'd stop until it was over.
Oh well it's your choice but it seems strange to discuss tyre sizes etc for a long time and then buy track oriented tyres for the road.
I do realise that they are fitted to some cars from new e.g. Lotus I think.
Alphabettispaghetti
Club Member
I think i'll go 195/65/14 with the 4.44 on the main set.
datsfun
Club Member
Silly question but are they road legal ? I know the Toyo R888 are but I was under the impression that A048's were track only use ?
Also as pointed out, have you driven a car fitted with these type of tyres before ? Only reason I ask is that the grip is phenomenal when warmed up and they tend to make the car tramline like mad at lowish speeds. Parking is a nightmare unless you have power steering or biceps like our famous "Don Muscles" on here..
If the car will be be predominantly used for track , then they are a very good tyre. All IMHO.
Alphabettispaghetti
Club Member
I think they're road approved?