Technical yet another alloy wheel thread...

[ronnieronson]

So, I've read the guides (many - and not just on this forum!), and I'm still confused!

I've been offered some 13" alloys which have a 4x98 stud pattern, an offset of 38 and tires at 165 70 13.
The wheels are 5.5j wide.

My 899 cinq is currently sat on 13" sporting alloys which went on no problems, without spacers - but I have no idea what offset they are.

So basically - will these new wheels fit without much messing around and does anyone know what offset my cinq sporting wheels are?

 

[fingers99]

OK. Somewhere j333evo has posted the offset for the standard sporting wheels, (and I'm sure that it's actually stamped inside the wheel if you look hard enough) but:

The more offset, the closer the tyres are to the arches. With 38et, you'll need something like 3mm at the rear (each side) -- you could use the standard sporting spacers which your car should have at the front, and something in the order of 12mm at the front. You may be able to get away with 8mm, but turn in will be better with 12.

The spacers (at least, the fronts) should be hubcentric, you should (ideally) go for a stud conversion, 185/50 would be a better tyre, you should also lower it and fit an arb (others will argue about this).

Of course, some of these mods are about safety and performance rather than looks.....................

 

[chaos]

Standard Sporting setup is 30.5 ET alloys with 3mm spacers on the front.

IMO the tyres would be too large (165/70).

If I'm right, you'd need 8mm spacers on the rear and 11mm spacers on the front if you were to get almost the exact centreline as a standard Sporting for ET38.

You would also need to lower it to prevent 'elking' and a good mod would be to fit a Sporting ARB.

 

[chaos]

The spacers (at least, the fronts) should be hubcentric, you should (ideally) go for a stud conversion, 185/50 would be a better tyre, you should also lower it and fit an arb (others will argue about this).

You've got 185/50 on the brain You can't get 185/50/13 AFAIK - the usual tyre of choice is 175/50/13 (fairly easy to get hold of, good makes are slightly cheaper than Pirelli/Goodyear 165/55/13 which are standard Sporting fitment).

 

[fingers99]

You've got 185/50 on the brain

No, I've got 195/45 on the brain!

You can't get 185/50/13 AFAIK - the usual tyre of choice is 175/50/13 (fairly easy to get hold of, good makes are slightly cheaper than Pirelli/Goodyear 165/55/13 which are standard Sporting fitment).

You may be right about the 185/50/13 -- strangely (might have been a slip of the finger) someone mentioned them on CC, so I assumed they existed. I can't find any in the tweeks catalogue and don't have time to trawl through the Bridgestone pdf right now. They'd be a great choice for Cinqs and minis if someone made them, though!

 

[ronnieronson]

Standard Sporting setup is 30.5 ET alloys with 3mm spacers on the front.

IMO the tyres would be too large (165/70).

If I'm right, you'd need 8mm spacers on the rear and 11mm spacers on the front if you were to get almost the exact centreline as a standard Sporting for ET38.

You would also need to lower it to prevent 'elking' and a good mod would be to fit a Sporting ARB.

Hmm, ok - well AFAIK there are no spacers on my current wheels, and they fit / turn very well with no scrubbing.

So basically these wheels would fit ok - but I'd need spacers front and rearto prevent any scrubbing on the wheel arches?

Lets see if I have this right in my head - the bigger the offset, the further into the arch the wheel will sit unless it is spaced out?

 

[fingers99]

Lets see if I have this right in my head - the bigger the offset, the further into the arch the wheel will sit unless it is spaced out?

Yes. In effect, the spacers reduce the offset.

It would seem -- as you're not the first person to have fitted sporting alloys without the front spacers -- that FIAT fitted them to make the car handle better, not just for fit.

 

[ronnieronson]

Yes. In effect, the spacers reduce the offset.

It would seem -- as you're not the first person to have fitted sporting alloys without the front spacers -- that FIAT fitted them to make the car handle better, not just for fit.

I'm assuming you mean as part of the wheel?
My wheels are from a 97 cinq sporting - but wern't put on the car in any particular order (ie - fronts could have ended up on the back for all I know),
Yet my standard cinq is a 93 - the first model in the uk...

 

[chaos]

I'm assuming you mean as part of the wheel?
My wheels are from a 97 cinq sporting - but wern't put on the car in any particular order (ie - fronts could have ended up on the back for all I know),
Yet my standard cinq is a 93 - the first model in the uk...

No, the spacers are separate of the alloy.

 

[ronnieronson]

No, the spacers are separate of the alloy.

hmmm, well no spacers then AFAIK

 

[ronnieronson]

Just taken a look at the tires on my current wheels and printed on them is "155/70R13".

I understand that the 13 bit refers to my rim size - am I right in thinking that the 155 bit is to do with the width of the tire? and that the 70 means the sidewalls are as tall as 70% of the width (ie. 155 / 70 = 108.5)?

If this is the case then what size tires do the sporting wheels come with from stock? and would having my sizes on them affect the speedo in any way?

If I get these new wheels would it be a good idea to re-rubber all 4? - what size should I go for?

 

[chaos]

Just taken a look at the tires on my current wheels and printed on them is "155/70R13".

I understand that the 13 bit refers to my rim size - am I right in thinking that the 155 bit is to do with the width of the tire? and that the 70 means the sidewalls are as tall as 70% of the width (ie. 155 / 70 = 108.5)?

If this is the case then what size tires do the sporting wheels come with from stock? and would having my sizes on them affect the speedo in any way?

If I get these new wheels would it be a good idea to re-rubber all 4? - what size should I go for?

Read post 4

 

[ronnieronson]

Read post 4

Ah Sorry...
...So let's see if I have this straight - In theory, it shouldn't be possible to mess up my speedo, because tire side wall heights correspond to the overall size of the tire?

So if I get these wheels I can get a set of 175/50/13's, and they will not only be a suitable fit, but will also not bugger up my speedo readings?

Gaaaaah! this tire issue is so confusing!

Never actually done it but i keep thinking it might be a good idea to get a mate to pace me at 30 to see if my speedo is accurate...

 

[chaos]

Ah Sorry...
...So let's see if I have this straight - In theory, it shouldn't be possible to mess up my speedo, because tire side wall heights correspond to the overall size of the tire?

So if I get these wheels I can get a set of 175/50/13's, and they will not only be a suitable fit, but will also not bugger up my speedo readings?

Gaaaaah! this tire issue is so confusing!

Never actually done it but i keep thinking it might be a good idea to get a mate to pace me at 30 to see if my speedo is accurate...

Have a look on here - http://www.rochfordtyres.co.uk/tyrecalc.asp

 

[StoneNewt]

Point of intrest, I find my Sei's speedo is inaccurate in a non-linar fassion (in that it's more out at 60mph than at 50 or 70 :bang so the only way to actually have a decent idea of the real speed is the tacho which is more-or-less bang on the engine rpm and do a little in-head calculation the problem with this however is you need to know what the mph/1000 rpm is

 

[ronnieronson]

Have a look on here - http://www.rochfordtyres.co.uk/tyrecalc.asp

Thanks for that link chaos - seemed to help clear up a few thoughts in my head.
Having thought about this (and concidering that my current tires are almost brand new), I think I'm simply gonna get my tires swopped over on to the new wheels - they should fit fine (according to that calculator they would be suitable for anything between a 4.5" wide rim, and a 6" rim), and so long as my speedo is currently accurate then nothing much will have changed.

It does beg the question though - what are the tire sizes on bog standard stock tin pot cinq rims? - If I knew that I could probably work out how much (if at all) my speedo is out since I got the new tires in January...

:worship: