For a robust tire, go with 245/45x18. See mine for reference:

stock wheels 8"x18" ET 43 with 245/45x18 Pirelli Sottozero 240 RFT:



OEM M3 wheels, 8.5"x18" ET 29 with Bridgestone 960 All Season Pole Position:

 

Ok, my apology for "incomplete thoughts"... it's actually lack of knowledge on the subject which is why I'm asking for help.

let me try again: I don't want to lower my E61, it scrapes on ramps already even in "lifted" xi setting like we have here in the US. I would like to fit a 19" rim and thought that going with a slightly taller tire sidewall than what I see most others using (in whatever the appropriate width is(35 aspect ratio and 30 rear with staggered setups) would increase the overall diameter thereby decreasing the wheel gap, without having to lower the car. I also don't know the pros/cons of a staggered vs square setup except I assume the square setup allows you to rotate tires thereby extending tire life?

thanks for any info!

 

yes, equal 4 tires allows rotation and longer life. I have directional tires but can at least swap front and rear same side or like recently, my full size spare was flipped to go onto the other side putting the most worn tire into the car as the spare. The tire shop does these swaps for me free of charge.

I wouldn't call the car "lifted". It is a very appropriate height for the size and weight car. A Subaru Outback or Audi Allroad are "lifted". There's no sense, in my opinion, in having a big travel wagon that is going to bottom out just driving to a hiking trail head because it got lowered for looks.

Plus, I think lowering to decrease fender gap generally looks lame. I prefer a concentrically equal reduction in fender gap. When people drop the car, the top gap shrinks but not the sides, looks silly to me, or at least less cool than it can look if a little more effort is given.

If you must have 19's, then go up to the 40 series, the width is going to depend on the rim width as stated already. You shouldn't be putting a 255/40 onto an 8 or 8.5" rim, 9" should be the minimum.

 

1010 Tires.com recommends that you don't increase the overall size of the wheel (tire + rim) by more than 3% overall from original specs 225/50/17. Going to a 245/40/19 would be slightly greater than this (3.22%). They mention brake failure problems??? See link .http://www.1010tires.com/TireSizeCal...?action=submit and put in the dimensions. Going from a 225/50/17 to a 225/45/18 also exceeds this 3%. Are you experiencing any brake problems? I would think the standard brakes are capable of dealing with a greater than 3% increase in overall diameter...

 

considering brakes of similar size are used on other bmw's which comes oem with larger overall tires diameters, I'm not too worried about my brakes.

what did I increase by anyway - let's see - oem is 25.7", new size is 26.7" = 3.8% Not really an issue.

 

I agree with you on how to best reduce fender gap, which is why i was thinking that if I upgraded to 19" i would want an overall slightly larger diameter, which would preserve tire sidewall for compliance also. The wheels Im' looking at are some new csl replica spin-forged wheels which modbargains is advertising for a great $1000 price for 19"... they weigh 22lb, which is less than my stock 18" wheels I have now.

So, now that (thanks to you guys) i've established that the 255/40/19 is too wide for this car, I'm not sure I can do this as the 245/40/19 from what I can tell doesn't work (and would look awfully tall.) I'm sure someone has tried this switch, but until I find a pic I'm not going for this yet, too much risk in ordering wheel/tire combo which either doesn't fit or looks stupid.

 

are you comparing tire specs on tire rack? 245/40x19 would be identical to my tires just about exactly. mine are 18" 245/45. when you go up 1" in rim, the profile has to adjust by "5" 18 to 19 = 45 to 40

yes, i would have 1/2" more sidewall but you'd have the same overall diameter.

now, to address what you said "255/40x19 ...too wide" I would not say that but it may be too large in diameter. the 255 width just needs to be on the right rim width. using the right offset, you can definitely fit a 9" wide wheel which is what the 255 ought to go on.

being that you are looking at aftermarket wheels, i am sure you could find a 9" with correct ET, but it may not be cheap because they will be less common than a 8" to 8.5" wide rim. If I were you, I'd find either the right 9" wide wheel, which may actually require a 255/35x19 or just stick with the clearly functional 245/40x19 and 8" to 8.5"

In fact, one that comes to mind is the x3 based 5 spoke wheel in 19". style 128, 19" x8.5" for the front and you could just use two fronts, or you could deal with getting the tires equal and use the 9" rears. http://felgenkatalog.auto-treff.com/ look under e60, then 128 and see the x3 listing.

Actually, I bet the same tire would fit on there just fine. The front would be very square sidewall with 245/40 and the rear would be just a little stretched, which I would rather do than deal with different tire sizes that aren't quite right, but there are sometimes perfect sets, you just can't be rotating wheels when the rims are not all equal.

 

I don't get your logic at all.
245/40/19 would be in fact LOWER than 255/40/19.
I.e. the tyre would be narrower and lower, on the same 19' rim.
Plus, this is the stock size on the E63/E64 - look up any pics on the web and you will see how it looks in the flesh.

 

by tall, I meant the width/height of the tire. Thanks for the reference to the 6 series, checked out the pics. It would be cool to see these 245/40/19 tire/wheel combo on an E61 though as it seems like a logical way to reduce the wheel gap, without lowering the car. I thought others would have done this mod already and there would be pics. guess not. At this point I think I'm going to go for it... Modbargains has a great CSL replica spin forged 19" rim which they say weighs 22lb, and it's perfect for what I need. I'll go for a square setup so I can rotate wheels. Hopefully the reduced weight of the wheel vs the stock ones will balance out the increased weight of the tires so I won't sacrifice performance (acceleration/fuel economy) for the sake of appearance.

 

Are you going to sell your current setup (bmw 189 rims I am assuming)? If so let me know, I might be interested if they are in very good condition.