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[mmurray]

So... xdrive, off ramps, and a season of autoX ate through my potenzas up front and I need to find replacements fast. I'm buying for my summer set on OEM 162s, but want to beef up the front to counter understeer/ allow for rotation. Wheel/tire sizes are below - can I fit 255/35/18s on an 18x8" up front without rubbing?

Style 162s
F: 8x18 EH2+IS34 (8" wide, 18" diameter, 34mm offset). R: 8.5x18 EH2+IS37 (8 1/2" wide, 18" diameter, 37mm offset)

Tire Options
(Factory) 225/40/18 front, 255/35/18 rear
(Planned) 255/35/18 square - is that possible?

EDIT: Tires currently considered in order of preference are Z2s, PSS, RE-11s.

Thanks!

[mmurray]

Bump with a followup idea - would 245 be the safe bet over the 8" up front? I want some beef for handling, but am concerned about sidewall roll (that's why I'm replacing - chunked the shoulder), but hopefully higher performance rubber (z2s) will help.

[BMWE90 ModMaster]

with those widths and offsets you should have NO problem.

[Nitrous Garage]

X2 that setup will work

[007_e350]

Pss has shoulder thread designed for aggressive handing, plus it runs a size wider, anything wider than a 235 pss would rub on uturns

[mmurray]

Originally Posted by 007_e350

Pss has shoulder thread designed for aggressive handing, plus it runs a size wider, anything wider than a 235 pss would rub on uturns

Are you sure? I'm looking at 245s and almost pulled the trigger right before seeing this reply

[CSBM5]

Originally Posted by mmurray

Are you sure? I'm looking at 245s and almost pulled the trigger right before seeing this reply

Years ago when my daughter's E46 had an issue, we used the E90 330i for an autocross (D-stock) and used the SSR wheels from the E46. The fronts were 8x18 ET40 with BFG R1 265/35-18 tires (rear were 8.5 ET44, same tire), and we had no issues with tire clearance either strut-side or fender-side. R1s run very wide compared to street tires. The stock E90 8" wheel offset up front is 34mm, so these wheels were inset by 6mm fwiw.

I don't think you'll have any issue with the 8.5/255s up front.

[mmurray]

Originally Posted by CSBM5

Years ago when my daughter's E46 had an issue, we used the E90 330i for an autocross (D-stock) and used the SSR wheels from the E46. The fronts were 8x18 ET40 with BFG R1 265/35-18 tires (rear were 8.5 ET44, same tire), and we had no issues with tire clearance either strut-side or fender-side. R1s run very wide compared to street tires. The stock E90 8" wheel offset up front is 34mm, so these wheels were inset by 6mm fwiw.

I don't think you'll have any issue with the 8.5/255s up front.

Thanks! I'm still on the 8" OEM wheel up front though. I wanted to go wide up front, but I've scaled it back and was looking to go PSS in 235/40F 255/35R, but those rears are on national backorder apparently.

As DD/autocross tires, is there any issue with going up to a 255/40 in the back? Those are in stock

EDIT: CSBM5, your garage is amazing. Great taste

[CSBM5]

Originally Posted by mmurray

Thanks! I'm still on the 8" OEM wheel up front though. I wanted to go wide up front, but I've scaled it back and was looking to go PSS in 235/40F 255/35R, but those rears are on national backorder apparently.

As DD/autocross tires, is there any issue with going up to a 255/40 in the back? Those are in stock

EDIT: CSBM5, your garage is amazing. Great taste

I would guess that 255/40s are too tall, too large of a diameter, and might cause rubbing issues, but I've got no experience with those on the 330i.

Don't forget to take out the alignment pins up front and move the struts inward for maximum negative camber. The factory slots are small, so the gain in negative camber isn't much (nothing like camber plates would provide). Then align the car and set the front toe right at the min of the factory spec. It's the best you can do with a stock setup to decrease tire outside edge destruction.

[mmurray]

Originally Posted by CSBM5

I would guess that 255/40s are too tall, too large of a diameter, and might cause rubbing issues, but I've got no experience with those on the 330i.

Don't forget to take out the alignment pins up front and move the struts inward for maximum negative camber. The factory slots are small, so the gain in negative camber isn't much (nothing like camber plates would provide). Then align the car and set the front toe right at the min of the factory spec. It's the best you can do with a stock setup to decrease tire outside edge destruction.

Thanks! Definitely going to have to come in as much as possible up front - the Xi chews through those outside shoulders. I would do plates, but I'm otherwise bone stock and want to stay appropriately classed for SCCA. I tried to find some info on the E90 pins/ camber adjustment on here, but didn't find much. Is it a DIY job, or should I work with a shop for an alignment to do that?

[CSBM5]

Originally Posted by mmurray

Thanks! Definitely going to have to come in as much as possible up front - the Xi chews through those outside shoulders. I would do plates, but I'm otherwise bone stock and want to stay appropriately classed for SCCA. I tried to find some info on the E90 pins/ camber adjustment on here, but didn't find much. Is it a DIY job, or should I work with a shop for an alignment to do that?

Not sure about the Xi, but on the RWD E90 the pins simply unscrew from the top, you'll see them easily looking at the top of the strut tower. Then with the car jacked up, it's easy to loosen the three strut nuts a bit and slide the strut toward the engine on each side to get maximum negative camber.

Note that this changes the toe when you change the camber. The toe goes more toward toe out (at least on the RWD cars, I assume the Xi has the tie rods connected in front of the axle centerline like the RWD cars do). So it's a good time to get an alignment to the specs you want afterwards.

I removed the pins on my E90 M3 and used Rich's DIY thread here as a guide.

Cheers,
Chuck