[rwalker]

I've just mounted a set of d-force ltw-5s, 18x9 ET41. The fronts clear my struts by maybe 1mm in stasis (see pics). Unfortnately, under load and deflection, they don't clear. Tires are 255/35r18 Toyo Proxes R888s, and have plenty of clearance.

So: I'm shopping for spacers, and would like to run the absolute minimum thickness required, to maintain maximum fender clearance.

My question: does anybody have experience with the amount of hub deflection I should account for with 18s? I'd love to get away with 3mm H&Rs.

Another option I've considered is grinding away a bit of the wheel lip. Anybody every try that?

Pics below. I'm running stock Sports Package suspension with M3 control arms, which seems to providing plenty of fender clearance under compression right now.

Fender clearance under some compression:

[rwalker]

If I use a 3mm spacer, that should give me:

arcsin(3/(9*25.4)) = ~0.75 deg hub deflection

Sounds like plenty, no?

[2010MSPORT335i]

I would just run the spacer and see what the outcome is. 3mm is very minimal but should do the trick.

I am on coilovers and had the same problem, it was actually a stuck on wheel weight for me though -_-

[Ginger_Extract]

3mm should be plenty, and still allow the use of OEM bolts...

[rwalker]

Hrm. ECS sold me extended lugs for 3mm H&Rs...

Forgot all that math, just get a 3MM spacer, tape the strut drive around hard, hit some bumps check tape, if marked get a 5MM spacer that should be plenty of clearance on the strut side.

[rwalker]

Update: running 3mm H&Rs with stock lugs. All clear for aggressive street driving so far.

Current setup: 255/35r18 Toyo R888s on 18x9 ET38 all around. Camber: -1.1* (M3 arms and camber pins removed).

On a dry skidpad (cul de sac), the car still tends to push in steady state. Goosing the throttle sends me wide at first, then the tail comes around slowly. I have a Wavetrac LSD.

Camber plates are on order .

[The HACK]

Wait. Your WHEELS are deflecting enough to touch the struts?

There are bigger issues at hand than clearance, IMO.

[rwalker]

I don't know which piece was deflecting that fraction of a millimeter, I can think of a few candidates: the wheel, the hub on the bearing in relation to the knuckle, or the strut itself could have bent a bit under load (I doubt it was the knuckle itself). Wouldn't have taken much, but something for sure changes under load.

[The HACK]

It anything, tire sidewall will deflect far enough to rub LONG before any of the components you mentioned SHOULD deflect even a hair's width.

If any of the components you mentioned deflect under load something is very wrong with your car.

[rwalker]

The sidewall was definitely deflecting, but mostly at the bottom, by the contact patch. Next to the strut, the tire has lots of clearance.

Regarding your opinion on bearing (and other) deflection under load being "very wrong", there are many who disagree with you. To find some of their opinions, Google "bearing deflection under load".

[The HACK]

If the tire deflects on the bottom, it'll deflect on the top too.

Other people can have their opinions on it, I still contend that if your wheels are deflecting that much, and if your bearing is the culprit, there are more serious thing wrong with your suspension you need to worry about than clearance.

[Ginger_Extract]

Get camber plates. I have Vorshlag's on my 1'er, and they have been excellent for DD/AutoX/Track. With otherwise stock stock suspension my car is at -2.4* camber in the front.