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Discussion Starter #1 (Edited)
Hey guys,
I'm looking to purchase Style 172 E60 550i wheels and have them installed on my E39. I found a lot of people talking about having them bored out to 74.1mm however what about the offset? I believe the fronts are E18 and the Rear E32. If I was to purchase this for the rear would it work? http://www.turnermotorsport.com/html/detail.asp?PRODUCT_ID=3075740725<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com<img src=" /><o:p></o:p>
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And I guess the front would just have to be bored out since the offset is fine?<o:p></o:p>
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Thanks for all the help<o:p></o:p>
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ps: 245/35/19 tires at the front and 275/30/19 for the back<o:p></o:p>
 

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Discussion Starter #5
Yea the offset on the 122's is ET20 which would fit I assume, however I m not sure about the bore???
I've messaged turnermotorsport and they don’t seem to be sure either with the STYLE 172's on the E39 -
I hope that someone comes through with an answer :S
 

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off course u need to bore them, central hole in e60 its 72mm in E39 74,1mm

i did something like that:


I just did this and the drawing was very helpful. You don't need to remove all of the raised portion.

I used a nice Harbor Freight Center bore gauge set to 74.1:



High tech tools:



A drum sander and a drill and a few minutes and several sanding rolls later, the deed was done.




 

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Does the larger center bore translate to more load bearing capacity bc the load is spread around a larger circumference? Don't tell me its negligible. There's got to be a good explanations. BMW engineers do not fail like that.
 

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I just did this and the drawing was very helpful. You don't need to remove all of the raised portion.

I used a nice Harbor Freight Center bore gauge set to 74.1:



High tech tools:



A drum sander and a drill and a few minutes and several sanding rolls later, the deed was done.




You did this with a drill sander? How did you make sure the final bore was concentric? A bore gauge will only tell you the bore diameter, not concentricity.
 

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For the mid 80's M cars, BMW redesigned the venting on the rotors so air had to come from the wheel/hub area instead of what they do on every other brake rotor ever designed (by BMW or anyone else), where air is supplied from inside near the strut.

This design resulted in significant overheating and rotor warping. BMW replaced thousands under warranty until the aftermarket folks got smart and substituted 750 rotors instead (ie Dinan engr and others). Problem solved. I have an E24 M635 and experienced the brilliance of this design firsthand. I now run 840 rotors and have had no problems ever since.

Or I could also mention TRX metric rims that were supplied on the mid 80's cars as well. You could only buy ONE brand of tire for that rim (in either the 390 mm or the 415mm supplied on the M cars). Almost everyone who had the TRX rims has tossed them for aftermarket english sizes so at least they could buy decent tires.

I'm not trying to knock BMW engineering in general, but they have released some bonehead designs in the past and are not infallible. They might have had some reason to increase the wheel bore to 74 mm on the E39, but the fact that every other car produced after it still uses 72 mm makes you really wonder what the purpose was.
 

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I could also mention TRX metric rims that were supplied on the mid 80's cars as well.
I know all about this. Most owners today have BBS rims on their 80s BMWs. I guess BMW was counting on it to catch on? :dunno:

I'm not trying to knock BMW engineering in general, but they have released some bonehead designs in the past and are not infallible. They might have had some reason to increase the wheel bore to 74 mm on the E39, but the fact that every other car produced after it still uses 72 mm makes you really wonder what the purpose was.
I'm hoping someone here would have some inside on this. I agree the Germans tend to make some bonehead mistakes/decisions.
 

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I know all about this. Most owners today have BBS rims on their 80s BMWs. I guess BMW was counting on it to catch on? :dunno:
BMW had a collaboration with Michellin in the 80's and the TRX concept was born. Michellin, however, really did not support the concept as they made basicly one type of tire for the rim, which made weird sounds and was an average performer at best. No other manufacturers could be convinced to make tires (or maybe they were prevented by excusivity) for the TRX rims and they soon died.

There was another element to the collaboration (since you mention BBS) which was a joint design by BBS, Michellin, and BMW to build the three pc BBS 415 mm for the M635. This was a big failure as soon after introduction, customers were cracking these rims and experiencing blow outs and tire failures. It was unclear whether it was the tire manufacturer or BBS that were to blame; some claimed the rims were cracking and that led to loss of air; others claimed the sealing bead on the tire failed which led to loss of air, the rims cracking after deflation. In any case BBS had a recall of all 3 pc M635 TRX rims, and replaced them with 415 mm single pc forged wheels. These had no problems. I actually still have my set (although I don't use them any longer).
 

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You did this with a drill sander? How did you make sure the final bore was concentric? A bore gauge will only tell you the bore diameter, not concentricity.
And people ask me why I don't post very much anymore hiha

I guess I am DOOMED then :rofl:

If you think you can take aluminum off that fast with sandpaper, think again.

I tested the wheels on the car at highway speeds and there are no vibrations, so I guess that I cheated certain death. :goldcup:
 

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And people ask me why I don't post very much anymore hiha

I guess I am DOOMED then :rofl:

If you think you can take aluminum off that fast with sandpaper, think again.

I tested the wheels on the car at highway speeds and there are no vibrations, so I guess that I cheated certain death. :goldcup:
Your quote: "A drum sander and a drill and a few minutes and several sanding rolls later, the deed was done."

What am I supposed to believe??? If you would have added the part about the wheel lathe I would have understood...

Sorry if I took your post at face value.
 
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