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[slay2k]

Hey boys,

Moved to Puerto Rico and have been driving around in constant potholes, including highways. I'm running 235/35/19 front (3.2" sidewall) and 265/30/19 back (3.1" sidewall) and they cannot tolerate these roads without serious pain and damage.

Just drove my buddy's Tesla on 235/45/18s (4.2" sidewall) and hardly felt any bumps at all. I'd like to downgrade but can't decide if 18" will be enough extra sidewall since the stock 18" sizes for my 2007 335i (Sedan) seems to be 225/40/18 front and 255/35/18, both of which have only a 3.5" sidewall.

Can I tweak those 18 sizes to increase the sidewall without affecting the handling too badly? If not, will a 0.4" increase in sidewall (3.1 -> 3.5) make any difference? Should I consider 17s?

Any help appreciated!

Cheers.

[tcphoto]

I just installed 235/40/18 and 265/35/18 Michelin PS4S on my Style 189's and am happy with the setup.

[ewicky]

Remember that thousands of E9x left Germany with 17" wheels destined for NA. Thousands more left with 16" wheels destined for places with even rougher roads.

I wouldn't consider 18" in your shoes. With our car's designed circumference, 18" are for good roads/handling/racing. 17" for casual drivers. 16s for challenging conditions. 19" for people that want to look ricy.

[TheMidnightNarwhal]

Originally Posted by ewicky

19" for people that want to look ricy.

Hey!

[ewicky]

Originally Posted by TheMidnightNarwhal

Hey!

Hahaha I meant it tongue-in-cheek. I guess it's personal opinion. I like a little meat (and air) on my wheels, not a hunk of aluminum encircled by a rubber band.

[TheMidnightNarwhal]

Originally Posted by ewicky

Hahaha I meant it tongue-in-cheek. I guess it's personal opinion. I like a little meat (and air) on my wheels, not a hunk of aluminum encircled by a rubber band.

[slay2k]

Originally Posted by tcphoto

I just installed 235/40/18 and 265/35/18 Michelin PS4S on my Style 189's and am happy with the setup.

That's 3.7" of side wall vs my 3.1". How does it feel going over big potholes? And how tight is your suspension?

[slay2k]

Originally Posted by ewicky

Remember that thousands of E9x left Germany with 17" wheels destined for NA. Thousands more left with 16" wheels destined for places with even rougher roads.

I wouldn't consider 18" in your shoes. With our car's designed circumference, 18" are for good roads/handling/racing. 17" for casual drivers. 16s for challenging conditions. 19" for people that want to look ricy.

These are interesting points. It looks like an equivalent setup for 17s would be 225/45/17 front & rear, giving a 4" sidewall. It would also bring the width down to 8.9", from 10" in the back. Would there be any downsides going from a staggered setup to non-staggered all around like this?

[JeanCa]

Originally Posted by slay2k

Hey boys,

Moved to Puerto Rico and have been driving around in constant potholes, including highways. I'm running 235/35/19 front (3.2" sidewall) and 265/30/19 back (3.1" sidewall) and they cannot tolerate these roads without serious pain and damage.

Just drove my buddy's Tesla on 235/45/18s (4.2" sidewall) and hardly felt any bumps at all. I'd like to downgrade but can't decide if 18" will be enough extra sidewall since the stock 18" sizes for my 2007 335i (Sedan) seems to be 225/40/18 front and 255/35/18, both of which have only a 3.5" sidewall.

Can I tweak those 18 sizes to increase the sidewall without affecting the handling too badly? If not, will a 0.4" increase in sidewall (3.1 -> 3.5) make any difference? Should I consider 17s?

Any help appreciated!

Cheers.

Hi, I'm from Puerto Rico. Currently running Apex arc-8 17s on my e92 with 245/45R17 & 255/40R17. I came down form having 19s which was horrible for roads here. Currently happy with my 17s. I always try to evade any pothole, but occasionally I run into some, and so far I have not bent/cracked any wheels. Once I took a huge pothole and tough I had destroyed 2 of my wheels, went to the tire shop and they told be that the wheels were fine.

I do not know the measurements of my tires sidewalls tho. They are Michellin PSS (front) and Hankook RS-4 (rears) if you wish ti research.

[slay2k]

Hah cool man, which part of PR? I'm by Old San Juan. And according to tiresize.com you've got big 4.3" front and 4.0" sidewalls but your diameters are 25.7" in the front and 25" in the back. I'm not sure if having different diameters is a good practice?

Also if you check out this old thread of mine, I've had major rubbing problems when I first bought the car and it had a 275/35/19" rear (26.6" diameter vs your 25.7")

We have similar looking rims, btw

[slay2k]

Sorry, edited my last post as it had incorrect numbers.

[tcphoto]

Originally Posted by slay2k

That's 3.7" of side wall vs my 3.1". How does it feel going over big potholes? And how tight is your suspension?

I haven’t encountered any large potholes with this setup. But, I did in my E46 and it tore up the two left side tires. The suspension on my E92 is stock and my local Indy commented on how tight it drove. I’m not into the stretched look and I cannot imagine how firm a low profile tire rides.

[328iking10]

Originally Posted by tcphoto

I just installed 235/40/18 and 265/35/18 Michelin PS4S on my Style 189's and am happy with the setup.

Is this 18x8-18x8.5

Originally Posted by JeanCa

Currently running Apex arc-8 17s on my e92 with 245/45R17 & 255/40R17 ... They are Michellin PSS (front) and Hankook RS-4 (rears)

Post pics please

Also, what are your wheel and suspension specs?

[JeanCa]

Originally Posted by FCobra94

Post pics please

Also, what are your wheel and suspension specs?

Wheels are Apex ARC-8 17x9et30 front and rear. I have 5mm spacers in the front to clear my coilovers which are ST XTA. Currently have -1.5 camber front and -1.8 in the rear. Also I have front and rear Upper and Lower M3 control arms and M3 strut brace. Thats all I got for upgraded suspension bits. I used to have PSS 245/45 on all 4 wheels but I was getting wheelspin under heavy throttle and the Traction control would come on frequently. So I decided to get stickier tires for the rear. So went with the Ventus RS4 (did not go with RE71R since the RS4 are cheaper, last longer and sound less on the road). That solved traction problems and I currently love my setup.

[nsjames]

I have 245/40 18s.
it's nearly 4" of sidewall, none run flats.

they still ride harsher than the factory 17" tire size.

I'd go to 17's in your shoes. There are days I regret 18's.

[slay2k]

Yup, I ended up getting OEM 17" (style 161) staggered. Ride quality much improved but the handling definitely softer (esp. steering response).

[slay2k]

[Update 9 months later]

So I've been running on the 17s for a long time now. Ride was comfy, but steering response slow and not to my liking. This became particularly noticeable when I upgraded suspensions to a Bilstein B12 w/ Eibach Prokit, and M3 front upper / lower control arms, which put me at close to -2 camber up front. The rest of the car was planted (no roll), but the tires were making it "laggy" and slow to respond.

I swapped them out for my old banged-up 19s (VMR V713 19x8.5f, 19x9.5r) wrapped in Hankook Ventus V12 Evo2s and the steering response is MUCH better. Fun fact -- with a new suspension hitting bumps in the road is nowhere near as jarring as it was before! One of the rear tires developed a sidewall bubble whilst sitting on my balcony, so the shop temporarily gave me a Pirelli PZero Corsa, which meant I was running mixed brands on the rear. Upon flashing to MHD Stage 1+, I started to spin the rear tires easily, which I suspect is due to the mismatched tires, so now I have a decision to make.

I need to decide what wheel size + tire combo will give me sharp steering response and enough grip to handle 400whp+ in the rear. I'm considering the following 3 options:

1) Put better tires (e.g. Michelin PSS) on my 17" rims, which are currently running Toyo Proxes Sports. Not sure if this would improve steering response / grip enough.
2) Buy a new set of 18" rims and slap some PSS tires on them.
3) Repair my 19s and put PSS tires on them.

None of these are particularly cheap, but I know that at least with #3 I'd get to keep my sharp steering response. Not sure how 18s would fare, and definitely not feeling optimistic about 17s in that regard.

Thoughts welcome!

Originally Posted by JeanCa

I used to have PSS 245/45 on all 4 wheels but I was getting wheelspin under heavy throttle and the Traction control would come on frequently. So I decided to get stickier tires for the rear. So went with the Ventus RS4

Woah...look at how much wider those Hankooks are than the PSS...nice

Originally Posted by slay2k

1) Put better tires (e.g. Michelin PSS) on my 17" rims, which are currently running Toyo Proxes Sports. Not sure if this would improve steering response / grip enough.
2) Buy a new set of 18" rims and slap some PSS tires on them.
3) Repair my 19s and put PSS tires on them.

Ok, so, what tires are on there now? That obviously makes a big difference when trying to recommend something "better."

I'm currently running Style 393 and factory tires (225/50/17) and can tell you that they "respond" better and have just as good, if not better, straight line traction @ ~400whp than the 245/40/18 DWS tires I had for ~60k miles previous...it's all relative.

[slay2k]

All except the rear passenger tire are Hankook Ventus V12 Evo2s, staggered 19" config (235/35/19 & 265/30/19). The rear passenger is, temporarily, a Pirelli PZero Corsa.

What are "factory tires" and what is it about your setup that you believe makes it respond better (esp. WRT steering) ?

[iqraceworks]

Originally Posted by tcphoto

I just installed 235/40/18 and 265/35/18 Michelin PS4S on my Style 189's and am happy with the setup.

I'm getting ready to run that exact setup.......

Originally Posted by slay2k

What are "factory tires" and what is it about your setup that you believe makes it respond better (esp. WRT steering) ?

The factory tires are whatever Conti run flats came from the factory on the previous gen 4 series.

Even though they are taller than my last set of wheels/tires, the stiffer sidewall and narrower size definitely adds to that "better response."