17inch alloys

[Dr Forinor 0]

Right, a friend once told me that if you put on alloys that are bigger than the original size, you need to go down in profile size as such also, for example;

 

205/50 15

205/40 16

205/30 17

 

Ie, taking off 10 from the profile size each time you go up an inch in alloy size, if you dont then you risk excessive wear and tear to components such as CV joints (I think it was) and a couple of other things he mentioned.

 

He also said that odometer would be out and the speedomoter would be out aswell, and that it would affect the geometry too.

 

Can someone clarify this please? And possibly elaborate?

[sciroccotune 0]

Well you are meant to try and keep the rolling diameter as close to stock as possible to avoid such problems...

 

check this out: http://www.miata.net/garage/tirecalc.html

[Dr Forinor 0]

That's a good site, handy to know that. Any info on how if affects other parts of the car?

[sciroccotune 0]

TBH I think you would be hard pushed to really damage other parts of the car as long as they are installed correctly, sure some one will give there opinions also. of course more unsprung weight will affect handling

[Dr Forinor 0]

Well, just have to wait for someone else now, thanks for your input.

[Kevin Bacon 5]

The correct sizing is:-

 

205/50/15 - Standard

205/45/16

205/40/17

 

A 205/40/17 causes a 1.7% speedo under read, so barely noticeable. Sciroccotune is right, it's to keep the rolling radius the same as stock otherwise it affects the gearing.

 

You won't get any extra wear on anything since the tyres are all the same width, if anything, the 205/50 is wider than the 16 and 17" 205s.... if you go up to 215+ then it's more load on the steering components.

 

If you keep the weight as low as possible when upgrading wheels, then you're onto a winner all round.

[chrishill 0]

i think its about time someone posted a definative wheel/tyre guide and got it stickied, seems like alot of the same questions keep coming up! a nice guide explaining offsets, correct tyre sizes, widths and so on would be good.

[Dr Forinor 0]

If you keep the weight as low as possible when upgrading wheels, then you're onto a winner all round.

 

You mean as in have less people in the car? What happens if there is load on the upgraded wheels?

[Kevin Bacon 5]

As in keeping the unsprung weight to a minium. Everything below the spring basically is uncontrolled mass. Hubs, wheels, brakes etc. So if you start adding bigger discs and calipers, bigger wheels etc it's additional mass the chassis has less control over.

 

Bigger wheels are an additional rotating mass on the driveshafts too, so affects acceleration if they're heavy ones. It's all carefully worked out by VW for the best compromise, which is why they went with 15s. But if you're wise in your choice of tyre and 17" wheel, then you can still get a good ride and handling, but it's more critical with 17s.

 

For instance mine rides a lot better on 17" BBS RX (20lb) and Eagle F1s than it did on 17" RH ZW1s (24lb) with Kumhos. You're average 17" wheel and tyre combo tips the scales at 45lb. You really need to get it to 40 or below. The standard Speelines and Solitudes weigh 15lbs each, to give you an idea. 15" wheel and tyre combos average about 32lb.

 

Weight in the car is just additional bulk but is supported by the chassis, so all that happens there is the car slows down. Ever notice how much slower the car is when you fill the tank to the brim? 15 Gallons of fuel is roughly 60 kilos of dead mass!

[Dr Forinor 0]

Yeh, as soon as 1 person jumps out of the car, it instantly feels faster.

 

Well I did notice going from 17s to 15s (when I bought the car) that with the 15s, the car felt quicker, steering was lighter and also felt like it better control. I actually do want 16s (BBS RX) but I cant afford them right now so will just shove those 17s back on for the look, they (BK Racing 299) look better than the Solitudes

[Kevin Bacon 5]

I think that's what Gixxer has on his..... I don't like them personally, too fussy looking but I don't think they're especially heavy.

 

Everyone says that about 15s though, or thouse that are willing to admit it at least.

 

BBS RX look a lot better in 17" mate, I know it's an old cliche but the extra inch makes all the difference!

BBS just have an OE quality and feel to them and suit most VWs....and they're light and durable.

[Jim 2]

Theres a guy selling a set of refurbed BBS RX2's in 17" 5x100 on UKMKIV's at the minute for £400.. they look terrific on the Corrado - see Guy Hartleys Corrado if you need any proof of that! :)

[Dr Forinor 0]

Thanks for the advice Kev.

 

Any links Jim?

[Jim 2]

http://www.uk-mkivs.net/forums/304796/ShowPost.aspx

 

You will need to register though to read it and contact the guy over PM...

[Dr Forinor 0]

Thanks for that Jim.

 

Kev: I agree that 17s definitely look better, but dont the 16s handle better? I really noticed a lot of difference in handling going form the 17s to 15s in that the 15s handled better, without a doubt.

[Kevin Bacon 5]

Not especially mate. I've run 16s on mine and didn't notice any difference between them and 17s to be honest. Going from 15 to 17 is what you notice the most.

[Dr Forinor 0]

Damn you, now I'll have to get the 17s..... which means more money :oops: :roll:

[GIXXERUK 0]

think that's what Gixxer has on his..... I don't like them personally, too fussy looking but I don't think they're especially heavy.

kevhaywire,

 

not too keen on them myself mate , they arent offensive or attractive , they were on it when i got the car it

tbh i prefer a five spokes on the c and thats what i'll probably get but there's too much choice !! :-)

[Dr Forinor 0]

I think you have the shiny shiny ones, lol, chrome or whatever, I have the silver ones, but same design.

[GIXXERUK 0]

yep black chrome and a lot of people like them , i quite often get comments about them but as i said i like 5 spokes , i know this is like saying there isnt a god but i dont like bbs wheels either

 

ps they arent that shiny :-)

[Kevin Bacon 5]

not too keen on them myself mate , they arent offensive or attractive , they were on it when i got the car it

tbh i prefer a five spokes on the c and thats what i'll probably get but there's too much choice !! :-)

 

Fair dos chap 8) There's quite a few Cs sold on 17s. I know one or two VR owners that have never used 15s!! They don't know what they're missing!!

[Dr Forinor 0]

Fair dos chap 8) There's quite a few Cs sold on 17s. I know one or two VR owners that have never used 15s!! They don't know what they're missing!!

 

If you like the 15s so much, why change from them?

[bix 0]

Probably cuz 17s look 10x better :)

[GIXXERUK 0]

Probably cuz 17s look 1000x better :)

[logicaltuning 0]

this is exactly why i want rid of my 17s to go down to 15s - i prefer handling