MMI

So I upsized the fronts to 245/35/19 for my winter set and noticed the outer shoulder of the passenger side tire rubs the wheel well liner at the 10-o'clock position over bumps (where the liner bulges around one of the liner screws. Looking closer I noticed that the front passenger wheel is not centered in the wheel well (3-finger gap towards the front and 1.5-finger gap towards the rear). The driver's side seems evenly centered with 2-finger gap front and back. So I crudely measured the wheelbase using a tape measure and sure enough the driver's side is about 107.9" and passenger side is 107.3". You can kinda see it in the pics too. Could this be just an alignment issue? or something more serious? The car doesn't pull at all but I'll be getting alignment checked as soon as I throw my new summer tires on next month. Will the average alignment shop be able to identify the problem if it's a subframe issue or something else? I would appreciate the expert comments so I'm on the right track to getting this resolved.
thanks!

winterturb

Check around your sunroof see if the metal is bent. This will tell you if your structure is bent which can happen with hard pothole hits

I’d be inclined to take it to a shop and have it properly checked. Something is wonky and no telling if it’s the suspension or structure

Also they installed the wheels backwards. No biggie

lobuxracer

iTrader: (2)

Bent sunroof isn't causing this problem. It's a common problem with subframes like ours. A good alignment shop should be able to fix this by moving the subframe. It's clearly not square with the chassis centerline. While they're at it, have them balance left/right to get even camber on both sides of the front.

winterturb

I recall your post about the isf handling no better than the is250. Is it possible your front end has been this way since you got the car and only noticed it now due to the rubbing from upsizing the tires?

lobuxracer

iTrader: (2)

This would definitely compromise the car's handling. Step one in any chassis tuning is to ensure the axles are square with the chassis centerline and they're equidistant on both sides. If they're not, the car will not handle predictably, ever.

MMI

Thanks for pointing that out, you're probably right!
Thanks for the advice, now need to find a competent shop.
Cheers!

flowrider

iTrader: (9)

No probably about it. He is absolutely right.




Lou

Toprawman

My F was also uneven like yours. It is very common. Like said above check with a good alignment shop.

winterturb

Any updates?

MMI

It's getting checked out tomorrow. Will report back.

xdejablu3x

You ever compare castor? from the pictures that's what it looks like to me.

MMI

Update. So the alignment shop would not comment anything on whether the subframe is squared up or not. It was frustrating as they kept sidestepping any of my questions about the subframe. Either they didn't feel like checking it or they don't know how to, even though that was the first thing I had asked them about on the phone and they said yeah sure no problem. Anyway they explained to me that they shifted the front right wheel forward a bit by repositioning the lower control arm (I didn't know that was adjustable but I'm no expert). xdejablu3x, maybe what you mentioned was correct? Initial right caster was 8.0 deg, final 8.8. The wheel is now centered better in the wheel well but still not perfect, although I took it over several deep dips where it rubbed before and now no more rubbing!
The next thing that surprised me is that initial front toe was 0.10" toe-in each side! I told them to set it to 0.04 deg. toe-out as recommended by lobuxracer. To this they told me to not ever use degrees and use inches instead and they got really defensive and opinionated about it. I wasn't sure what that is in inches so I scrambled to lookup lobuxracer's post and found 1/16". Though I'm not sure if that's per side or total, I told them per side...I hope I got it right
So I went for a rather spirited drive on a windy highway along the coast last night to check it out. I couldn't go too hard as it was barely a couple degrees above freezing but immediately obvious was how much better the car turns in mid-corner. I mean it's just awesome. The front end just digs in and claws it's way out of the corner like never before. And this is on snow tires! I will need to retrain my brain for the car's new behaviour but I can definitely get used to this. And it's not just improved feeling as I took 2 rounds around a long sweeper that I take every day and normally max out at about 65 km/h on Michelin PS4S tires in the summer, now can take it at 70 km/h on snow tires . I can't speak of the effect on initial turn-in response just yet as the snow tires with full tread mask that anyway. Forgeline just shipped my new wheels today so I should be rollin on fresh Michelin PSS by next weekend. I can't wait to see how the car will feel and handle then!

lobuxracer

iTrader: (2)

There's no way they could adjust the LCA to make this change. Angles vs. mm is total BS. 1/16" out per side is just fine and turn in should be way better. Many shops toe-in knowing it will result in longer tire life. I argued with a tech about this briefly once and he shut up pretty quickly. The only way to eliminate unintentional toe out on turn it is to run different rear LCA bushings, but it sounds like they got you a whole lot closer to good than where you were. Congrats!

winterturb

That’s a big change. Glad it worked out!

lobuxracer

iTrader: (2)

So your alignment sheet is a dead giveaway for they only adjusted toe. The left right camber is horrible. 0.7 degrees difference between left and right makes it crystal clear your subframe isn't set properly on the chassis. You'd like your car even more if you can find someone who will solve this problem. You've still got a 1.1 inch wheelbase difference as well. They didn't hurt you, but they sure don't know much about aligning a car properly.