Apex Arc-8 Can't Decide 17s or 18s

[J0hnny Ray]

I was thinking of holding off on getting rims but I ended up blowing a tire on the freeway (135s are still fine) and so now may be a good time to get new wheels.

I'm torn between the two:

17x8.5 ET40 with 255/40R17s

OR

18x8.5 ET45 with 235/40R18s

I would like to go to a square set up and I have chosen the two tire sizes for the respective wheel diameters due to the similar prices of the tires. I know there's a group buy for the 18s right now so the overall wheel prices would be very close to similar.

[BMWCurves]

It really depends what your goals are:

• Cost: If you're looking for lower overall cost in the long run, between those two wheel/tire combinations, you'll probably save money on tires in the 17" setup. However, because of your chosen tire sizes, there probably won't be that significant of a difference in cost.
• Looks: It's completely personal. I think 18" wheels look more aggressive and suit our cars better than 17" wheels, but I am perfectly happy with my 17"s.
• Performance: I would wager the 17" wheel/tire combo you have picked out might provide better grip from larger section width tires. The difference in unsprung weight is a wash because the 17" wheel is about 1 lb lighter than the 18" wheel (17.4 lbs vs 18.2 lbs), but the 17" tire will be about 1 lb heavier than the 18" tire (22 lbs vs 23 lbs in Conti DW tires). However, the feel might not be as precise in the 17" setup because the 17" tires will have taller sidewalls compared to the 18" tires.
• Comfort: This one goes slightly to the 17" setup because the tires will have a taller sidewall to absorb bumps in the road compared to the 18" tires (4.02" vs. 3.70").

I don't think you can really go wrong with either wheel/tire combination. It's a shame you missed the 17" group buy. FWIW, I received my 17x8.5" ET40 Hyper Black wheels a few weeks ago and love them wrapped in 245/40R17 square Continental ExtremeContact DW tires. I landed on that setup after people gave me advice in on my thread contemplating a very similar dilemma to yours. You should take a look, it's got a lot of good info:

http://www.zhpmafia.com/forums/showt...Size-Questions

Finally, consider that the group buy for the 18" wheels only has Hyper Silver and Anthracite in the 18x8.5" ET40 wheel you're wanting, so that may limit your decision if you don't want those colors.

Hop that helps!

[slater]

FYI, apex says the 18x8.5 ET45 is a 1-series fitment. it does sit 4mm closer to the strut tube, and a 235/40/18 is a tiny bit wider than a stock 225/40/18. so i'm not sure if it will make contact. probably depends on the tire. i haven't measured yet, myself (considering this size too).

[J0hnny Ray]

It really depends what your goals are:

• Cost: If you're looking for lower overall cost in the long run, between those two wheel/tire combinations, you'll probably save money on tires in the 17" setup. However, because of your chosen tire sizes, there probably won't be that significant of a difference in cost.
• Looks: It's completely personal. I think 18" wheels look more aggressive and suit our cars better than 17" wheels, but I am perfectly happy with my 17"s.
• Performance: I would wager the 17" wheel/tire combo you have picked out might provide better grip from larger section width tires. The difference in unsprung weight is a wash because the 17" wheel is about 1 lb lighter than the 18" wheel (17.4 lbs vs 18.2 lbs), but the 17" tire will be about 1 lb heavier than the 18" tire (22 lbs vs 23 lbs in Conti DW tires). However, the feel might not be as precise in the 17" setup because the 17" tires will have taller sidewalls compared to the 18" tires.
• Comfort: This one goes slightly to the 17" setup because the tires will have a taller sidewall to absorb bumps in the road compared to the 18" tires (4.02" vs. 3.70").

I don't think you can really go wrong with either wheel/tire combination. It's a shame you missed the 17" group buy. FWIW, I received my 17x8.5" ET40 Hyper Black wheels a few weeks ago and love them wrapped in 245/40R17 square Continental ExtremeContact DW tires. I landed on that setup after people gave me advice in on my thread contemplating a very similar dilemma to yours. You should take a look, it's got a lot of good info:

http://www.zhpmafia.com/forums/showt...Size-Questions

Finally, consider that the group buy for the 18" wheels only has Hyper Silver and Anthracite in the 18x8.5" ET40 wheel you're wanting, so that may limit your decision if you don't want those colors.

Hop that helps!

These are the exact points I'm mulling over. The colors I'm torn between are Anthracite and Satin Black for my AW Sedan so going with 18s may make the decision easier. I figured that brake dust would be less visible on Anthracite anyways. My largest concern is that the rear tires may lose grip due to going from 255s to 235s. Does anyone have experience with this setup to chime in? I don't track my car nor would I say that I hoon it either; but I would say that once and a while I drive spiritedly.

If anyone else could also comment on the front fitment being closer to the strut assembly, I'd appreciate it.

[J0hnny Ray]

Just spoke to Ryan from Apex with my fitment question. They said that 255s will require camber plates up at the front. Also, the proper offset for the 18s is ET38 so it doesn't run into the strut.

[Bimmernate]

I currently have 17x9 et42 with 245 square, no rubbing and looks really aggressive. I downsized to 17s because i wanted a softer ride and less expensive tires. After having them for a bit I realized I really like the "meaty" look of the tires on 17s too, makes it look really aggressive in its own way.

I was too considering getting a set of 18s though (mainly because of the group buy deal). Can't you run 18x9 et42 with 245s square w/ no problems? The 245s on my 17x9 look great, they may look a tiny bit more "stretched" on an 18x9 since there is less side wall but not sure by how much, hopefully minimal.

[Aeternalis]

I currently have 17x9 et42 with 245 square, no rubbing and looks really aggressive. I downsized to 17s because i wanted a softer ride and less expensive tires. After having them for a bit I realized I really like the "meaty" look of the tires on 17s too, makes it look really aggressive in its own way.

I was too considering getting a set of 18s though (mainly because of the group buy deal). Can't you run 18x9 et42 with 245s square w/ no problems? The 245s on my 17x9 look great, they may look a tiny bit more "stretched" on an 18x9 since there is less side wall but not sure by how much, hopefully minimal.

That is so nice. Love me some wide wheels at that offset on the E46.