Mod advice... and info request...
#11
Senior Members
Join Date: Feb 2004
Location: Portugal
Posts: 523
Likes: 0
Received 0 Likes
on
0 Posts
My Ride: 2001 BMW 316ti, 2004 BMW 530d, 2006 BMW 530xd, 2013 BMW 320d touring, 2014 BMW 520d touring, 2016 BMW X5, 2020 BMW 320da touring, 2020 BMW 540i
Model Year: 1974
Engine: Flat six
![Talking](https://5series.net/forums/images/icons/icon10.gif)
If you prefer a classic style go for the new ones (18") but if you prefer a more sportive style you can find something diferent in BMW wheels.....
![Wink](https://5series.net/forums/images/smilies/imported/wink.gif)
#12
![Default](https://5series.net/forums/images/icons/icon1.gif)
Ski,
When you change the diameter of the wheel, your speedo will change. The speedo is calibrated to the diameter of the stock wheel.
First, measure the diameter of the stock wheel and then the diameter of the new wheel. Even though, the rim is 2" larger in diameter, the critical measurement is the difference in wheel diameter.
So, circum. = pi (diameter). Calculate the circum. of both and then you can determine the % error. For example, if your error is 10%, then with a larger wheel you would be going 66 mph if your speedo showed 60 mph.
I do know that GM (yes, GM - work with me here) allows for some adjustments for wheel diameter in its program. I can only imagine that has the same capability.
However, check the circumferences first and see if the error is even worth the trouble.
When you change the diameter of the wheel, your speedo will change. The speedo is calibrated to the diameter of the stock wheel.
First, measure the diameter of the stock wheel and then the diameter of the new wheel. Even though, the rim is 2" larger in diameter, the critical measurement is the difference in wheel diameter.
So, circum. = pi (diameter). Calculate the circum. of both and then you can determine the % error. For example, if your error is 10%, then with a larger wheel you would be going 66 mph if your speedo showed 60 mph.
I do know that GM (yes, GM - work with me here) allows for some adjustments for wheel diameter in its program. I can only imagine that has the same capability.
However, check the circumferences first and see if the error is even worth the trouble.
#13
Senior Members
Thread Starter
Join Date: Jun 2004
Location: Beautiful North Carolina
Posts: 358
Likes: 0
Received 0 Likes
on
0 Posts
My Ride: 2011 F10 528i - Imperial Blue, Oyster/Black, Premium, Premium 2, Cold Weather, Xenons.
![Default](https://5series.net/forums/images/icons/icon1.gif)
Thanks to everyone for your input! If I can just finalize the transaction, I'll soon have some mod'ed pictures.
Juan, I don't think we are going to have much luck getting any additional info on the rack attachments...
I have emailed several online dealers of parts, and have recieved no response. If only I knew who to e-mail at BMWNA for more info...
![Cool](https://5series.net/forums/images/smilies/imported/cool.gif)
Juan, I don't think we are going to have much luck getting any additional info on the rack attachments...
![Frown](https://5series.net/forums/images/smilies/imported/sad.gif)
#15
Super Moderator
Join Date: Mar 2004
Location: Pittsburgh, PA USA
Posts: 17,310
Likes: 0
Received 2 Likes
on
2 Posts
My Ride: G30 M550i
Model Year: 2018
![Default](https://5series.net/forums/images/icons/icon1.gif)
I posted the following in another thread back in June. It will give you an exact calculation of speedometer error and tire size differences:
I'm wondering if there needs to be a wheel/tire modification guide added to the soon-to-be-released FAQ?
Originally Posted by by Rudy in this thread: [url=http://e60.doit.wisc.edu/forums/index.php?showtopic=1328
http://e60.doit.wisc.edu/forums/inde...showtopic=1328[/url]]You can see all the calculations for yourself using the following calculators:
This one gives a clear explanation of speedometer error:
Speedometer error calculator
This one (using javascript) gives a whole bunch of information:
Javascript tire size calculator
Have fun!
This one gives a clear explanation of speedometer error:
Speedometer error calculator
This one (using javascript) gives a whole bunch of information:
Javascript tire size calculator
Have fun!
#16
Senior Members
Thread Starter
Join Date: Jun 2004
Location: Beautiful North Carolina
Posts: 358
Likes: 0
Received 0 Likes
on
0 Posts
My Ride: 2011 F10 528i - Imperial Blue, Oyster/Black, Premium, Premium 2, Cold Weather, Xenons.
![Default](https://5series.net/forums/images/icons/icon1.gif)
Well, I guess that answers that question....
![](http://www.hosnet.net/chuck/tiresize.jpg)
hmmmm one more revolution per mile...
Thanks for all the great info guys!
Gotta love this board!
![](http://www.hosnet.net/chuck/tiresize.jpg)
hmmmm one more revolution per mile...
![Fear](https://5series.net/forums/images/smilies/imported/fear.gif)
Thanks for all the great info guys!
Gotta love this board!
Thread
Thread Starter
Forum
Replies
Last Post
Trinity Autosport
Vendor Classifieds
20
09-22-2016 11:08 PM
umnitza
Vendor Classifieds
1
09-02-2015 11:28 AM
spediegunz
E60, E61 Parts, Accessories and Mods
0
08-30-2015 09:43 AM