E70 wheel alignment

[ard]

Originally Posted by 14thbmw

Mine doesn't "lumber". But it does handle pretty nicely, including turn in. If you can't tell a difference, can I suggest a Suburban?

My two cars are and M5 and a track prepped, modified 996TT.

So maybe the X5 does lumber a bit.

And my wife's X5 has adaptive drive. (A feature that adds far more to handling than screwing around with alignment specs, BTW.. Given your desire to get peak handling, I assume you have that, right? )

[insert comment that 14thbmw has been chasing 'handling issues' with his 2013 in other posts]

http://www.xoutpost.com/bmw-sav-foru...-handling.html





However, to moronically repeat the nonsense about 'turn in' and toe, for people that will never need to be concerned about turn in, does members a disservice. ESPECIALLY when people are just repeating what they heard from elsewhere.

Especially when your own set up isnt dialed in, eh?

Set your x5 to mid range of toe, then set it to 0.01-0.02...THEN come on here and talk about how horrific the turn in was at 0,01; how you just couldnt set up right entering the corkscrew or how you track times suck with the lower toe.




OP- you get to chose your specs and tell them where you want it. If you are going to just 'see what they use'...all I can say is good luck.

[14thbmw]

That's the point - you can have it set up a lot of different ways, with various tradeoffs, according to YOUR preference. You and I may disagree on what makes sense, but that's our choice, the vehicle allows for a range of setups and therefore handling and tire wear characteristics.

[ard]

Originally Posted by 14thbmw

That's the point - you can have it set up a lot of different ways, with various tradeoffs, according to YOUR preference. You and I may disagree on what makes sense, but that's our choice, the vehicle allows for a range of setups and therefore handling and tire wear characteristics.

Right, but your argument uses a canard- that 'toe in will help turn-in on an X5 with otherwise stock settings'

On an aggressive track set up you run negative toe on front and positive toe in the rear. Did you know that? Or are you running positive toe all 4 corners thinking this is the 'best' for turn in???

Do some research- that old wives tale is just that. From tirerack (not that I like them much, but their advice is usually well vetted):

Toe can also be used to alter a vehicle's handling traits. Increased toe-in will typically result in reduced oversteer, help steady the car and enhance high-speed stability. Increased toe-out will typically result in reduced understeer, helping free up the car, especially during initial turn-in while entering a corner.

My advice, above, is minimum toe so your car isnt skittish- slight negatve- and thats it. Turn in is not a consideration and if you want that, you dont toe the fronts!

IMO of course

[JBF]

Hi ard,

Sorry to resurrect an old thread but it seemed to make more sense than starting a new one. I've read this post and several others of yours including on bimmerfest.

My understanding is that for a standard E70 (not including X5M and possible adaptive drive models which could be different) it's the rear camber, rear toe and front toe that are directly adjustable - things like front camber may be affected by toe adjustment. Front camber can be changed with different control arms (really for accident repair) or other third party modifications. Rear camber should be adjusted first, followed by rear toe, then ensuring the SW is properly centred the front toe. The recommended settings are:

Rear camber: -1.3 (units?)
Front/rear toe: 0.01-0.02" from centre

Something that seems to be causing confusion in most of these threads is the unit of measure. Most people posting their figures are showing them in degrees and minutes while you specify (the toe at least) in " from centre.

Could you clarify by summarising the desired toe and camber settings (front and rear) in BOTH " and degrees/minutes? This way when I go to the alignment centre I can ensure that they get this correct.

Thanks.

[ard]

So the simple answer is that you want the toe set to 'just a smidge off 0.000'. SO if I use inches or minite-degrees, it is all pretty close. It isnt the number that is important, it is that you want it 'almost to zero, just a bit off'



if you take 0.02" at the outer edge of a 25" wheel/tire. then that is about 0.023 degrees which is about 0 degrees, 1.38 minutes.



https://robrobinette.com/ConvertToeInchesToDegrees.htm




So if you ask for 0.02" or 0.02 degrees, you are good.


Camber is in degrees.


AD and standard are the same, BTW.

[JBF]

Thank you ard I appreciate that info.

I finally decided to stick with the 20" staggered setup and RFL (was considering non-RFL or a 19" staggered setup).

I've ordered Dunlop SportMaxxx (not the GT as they are reported to aquaplane significantly more than the other choices). Phoned around a few tyre shops and alignment centres to get pricing and ask whether I can specify my own figures. Several of them blagged on about the range that the machine 'allows' them to set, even when I suggested that they could set it to the minimum in that range they were reluctant to accept that it might be possible - too used to dealing with clueless 'punters' in my opinion. In the end I called a BMW focused tuning company based next to a local race track and asked if they can recommend a place for alignment; they did and when I called the guy immediately said "for an X5 personally I would set '0' toe-in otherwise the tyres will wear on the edges, but if you want something else we can do that"; so that's where I'll be heading once the rubber is delivered in a couple of days.

Any harm in going with his suggestion of '0'; should I insist on 0'01"-0'02"?

Also what about tyre pressures - I was thinking go with the unloaded pilar pressures of 32psi all around and half a tank of fuel. It's usually just me in the car or me and the wife with a couple of sets of golf clubs over the weekend.

[ard]

Good response from the shop. If you have a chat with them, and said 'I just want a very slight bit of toe to prevent it from feeling squirrelly', he'd probably response "yep, sure- good idea'. I'd think. (Obviously run that through a proper English-to-english translator...)

Report back what he says and what you decide.

On tire pressure I run a bit high- I find it helps reduce the edge wear. 34 usually, 36 in the rear if we are loaded. But this is HIGHLY tire model dependent. I run much latitude Tour HP ZP.

[robnitro]

I was running 38 all around on the rft's because it actually felt better over bumps than 32. Since the rft have very stiff sidewalls a higher pressure gives more cushioning.

On my non rft snows 36 works well for wear and ride.

[JBF]

So then the question is what pressure to have put in them before the alignment... I’d imagine change in pressure might change the alignment to some extent?

[ard]

Originally Posted by JBF

I’d imagine change in pressure might change the alignment to some extent?

no it wont.


alignment is a suspension/wheel thing, not a rubber tire thing.