326 M sport alloy - alternatives to RFTs

BeemerGuy · Post by **BeemerGuy** » Mon Mar 02, 2020 4:49 pm

Hi All,

I realise this has been covered already at length at times but thought I'd ask as I wasn't quite sure of the 18" front 19" rear story, and also wanted the latest opinions.

I have the 326 M sports 19" front and back on a 2016 e89 S20i. They came with Bridgestone Potenza RFTs 255/30 91Y.

I assume the 18", 19" therefore does not apply to me as these are already upgraded wheels? Is there normally a wheel size difference on standards?

If I look at replacement tyres should I go for Michelin Pilot Sport 4s 255/35?….any specific variant, or is there something even better/better VFM?

Many thanks,
BeemerGuy

Rassi · Post by **Rassi** » Mon Mar 02, 2020 5:24 pm

Your wheels will be staggered, meaning that the rears are wider than the fronts. So the tyres currently on will be 225/35/19 and 255/30/19, front/rear. I am ditching the Bridgestone RFT myself, and will put PS4S on in 235/35/19 and 265/30/19, but this is subject to much debate. 255/35/19 rears is also an option.

BeemerGuy · Post by **BeemerGuy** » Mon Mar 02, 2020 5:48 pm

Thanks - I just checked and you're spot on: 225/35/19 and 255/30/19, front/rear as you said.

The 265/30/19 vs 255/35/19 debate is whether they are strictly insurable as the 265/30/19 size is potentially outwith tolerance more or less?

And you will go with an repair and inflation kit/compressor as an alternative to a space saver?

Leek78 · Post by **Leek78** » Tue Mar 03, 2020 9:54 am

my M326 rear wheel is cracked so I have brought some after market wheel but are 9j in the front and 10j in the rear, so up by .5j all round. The recommended tyre size for these is 235/35/19 and 265/30/19 respectively. But tempted to run 265/35/19 or 275/30/19 or 275/35/19 on the rear

R.E92 · Post by **R.E92** » Tue Mar 03, 2020 10:16 am

Leek78 wrote: ↑Tue Mar 03, 2020 9:54 am my M326 rear wheel is cracked so I have brought some after market wheel but are 9j in the front and 10j in the rear, so up by .5j all round. The recommended tyre size for these is 235/35/19 and 265/30/19 respectively. But tempted to run 265/35/19 or 275/30/19 or 275/35/19 on the rear

That's an increase of 1j. You need to check the offsets of those wheels, there's not much room to spare at those widths.

Leek78 · Post by **Leek78** » Tue Mar 03, 2020 10:40 am

et35 front and et38 rear's

Pickster · Post by **Pickster** » Tue Mar 03, 2020 10:57 am

Leek78 wrote: ↑Tue Mar 03, 2020 9:54 am my M326 rear wheel is cracked so I have brought some after market wheel but are 9j in the front and 10j in the rear, so up by .5j all round. The recommended tyre size for these is 235/35/19 and 265/30/19 respectively. But tempted to run 265/35/19 or 275/30/19 or 275/35/19 on the rear

Hi I thought the 326's were 8J & 9J so your up by 1 all round. I've got my eye on some 437's which are the same as your replacements 9J & 10J they have 255/35/19 & 275/35/19 so you should be fine with your temptations.

Pickster · Post by **Pickster** » Tue Mar 03, 2020 11:09 am

Good Point with the offsets I was assuming you were staying with the 29 & 40 as the 326's

R.E92 · Post by **R.E92** » Tue Mar 03, 2020 4:22 pm

Pickster wrote: ↑Tue Mar 03, 2020 10:57 am Hi I thought the 326's were 8J & 9J so your up by 1 all round. I've got my eye on some 437's which are the same as your replacements 9J & 10J they have 255/35/19 & 275/35/19 so you should be fine with your temptations.

Assuming those are genuine 437M wheels your fronts will rub a little with those tyres, go with 245/35r19 if you have a choice.

R.E92 · Post by **R.E92** » Tue Mar 03, 2020 4:26 pm

Leek78 wrote: ↑Tue Mar 03, 2020 10:40 am et35 front and et38 rear's

They should be OK. The 235 front tyres are a bit skinny for a 9J wheel though, that's right at the minimum.

Leek78 · Post by **Leek78** » Tue Mar 03, 2020 4:30 pm

so its looking like the consensus is, front go for 245/35/19 on the 9j et29, and 275/35/19 on the 10j et38

mr wilks · Post by **mr wilks** » Tue Mar 03, 2020 6:57 pm

Leek78 wrote: ↑Tue Mar 03, 2020 4:30 pm so its looking like the consensus is, front go for 245/35/19 on the 9j et29, and 275/35/19 on the 10j et38

IThe rear you propose could rub on arch trim in the bends or compression if you drove spiritedly compression

feel or look at the arch liner , its protrudes down with a defined lip

silly design for no apparent reason .
On those numbers i'd be thinking 265 35 or 275 30 unless another member has the same 10j et38 & can confirm for sure .

BeemerGuy · Post by **BeemerGuy** » Wed Mar 11, 2020 1:19 pm

You guys knowz tyres, I'm trying to follow....I'm assuming 9j is really 19" and the et29 is the distance from hub to edge....is that a standard distance for 326 without spacers (i assume no spacers is standard?)?

If I went for Michelin pS4 235/35 fronts and 255/35 rear I assume that would be fine... what I might be missing from the 265/30 rears would be a bit of extra width, and they'd be higher....
So the extra hight would give extra comfort, but I'd have less rubber on the road (and not look as cool), and also avoid some potential rub?

Have I understood correctly...I'm afraid I'm only a secret petrolhead wannabe...thanks.

Leek78 · Post by **Leek78** » Wed Mar 11, 2020 1:43 pm

9j is the wheel width, 9j = 9 inches, 10j = 10 inches. You're right on the "ET" being the offset from the wheel centre line to the hub face. 265/30 will give a little extra tyre wall height. But as youre running 255/35 its the best option on std wheels.

enuff_zed · Post by **enuff_zed** » Wed Mar 11, 2020 1:57 pm

Leek78 wrote: ↑Wed Mar 11, 2020 1:43 pm 9j is the wheel width, 9j = 9 inches, 10j = 10 inches. You're right on the "ET" being the offset from the wheel centre line to the hub face. 265/30 will give a little extra tyre wall height. But as youre running 255/35 its the best option on std wheels.

And I believe I'm right in saying the 'J' measurement is across the inner faces? In other words, the width the tyre has to fill.

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