18" wheels on my V6 - MustangForums.com

4.0L V6 Technical Discussions Any questions about engine, transmission, exhaust, tuners/CAI, or gearing can be asked here!
Sponsored by:
Sponsored by:

Thread Tools Search this Thread
Old 03-18-2014, 01:46 PM   #1
1st Gear Member
Thread Starter
Join Date: Aug 2012
Location: Pa
Posts: 65
Default 18" wheels on my V6

I just bought some used 18" wheels from a 2011 GT (the 5 spoke ones) to put on my 2012 V6. My stock 17" tires are 215-65-17 which are 28" outer diameter. The 235-50-18 that come on the 18" are almost 1" smaller diameter (27.25"). Does this make any difference? I have to put tires on these wheels, so I'm wondering, should I get a size that matches the diameter of the 17"s? That would mean I would need 235-55-18 that are 28.2" diameter. Does it make a big difference what side wall ratio (50 vs 55) I get?
mlud00 is offline   Reply With Quote
Old 03-18-2014, 02:26 PM   #2
3rd Gear Member
Join Date: Apr 2011
Location: Wisconsin
Posts: 918

You should be fine.
The tires on my 17" winter rims are 235-50-17 which are about 27.6".
I run 255-45-18 on my summer rims, which are about 27" . I check my speedometer with a Garmin GPS, they both read the correct mph. Here is a link for tires sizes and revs per mile that will take the work out of comparing tires.
Chromeshadow is offline   Reply With Quote
Old 03-18-2014, 02:41 PM   #3
harddock's Avatar
Join Date: Feb 2014
Location: MA
Posts: 24

If anything the smaller diameter tire will show a higher speed than you are actually going. 3/4" may be a negligible difference. It would theoretically rack up mileage quicker but again maybe not noticeably.
harddock is offline   Reply With Quote
Old 03-18-2014, 08:33 PM   #4
6th Gear Member
Nuke's Avatar
Join Date: Jun 2007
Location: PA to KY ('07) to IL ('09) to MS ('10) to FL ('11)
Posts: 16,186

With a difference in tire O.D., you'll need a tuner to adjust the tire revs per mile so the speedo is on but it'll also change your overall drive ratio. It's probably better to stick with or as close to the OE tire O.D. Other than the minor change in rotational mass with the larger wheels, you shouldn't notice any performance change unless you DO change the drive ratio with a different tire O.D.
Nuke is offline   Reply With Quote
Old 03-19-2014, 08:40 AM   #5
1st Gear Member
Thread Starter
Join Date: Aug 2012
Location: Pa
Posts: 65

Think Nuke hit the nail on the head. I don't really want to deal with re-setting speedo, or different drive ratio. That's why I'm thinking the closest diameter in 18" is 235/55/18which is 28.2". My 215/65/17 is 28.0" OD. I have time to decide, my stock tires still have a few miles on them yet.
mlud00 is offline   Reply With Quote
Old 03-19-2014, 09:04 AM   #6
4th Gear Member
audioAl's Avatar
Join Date: Mar 2012
Location: Texas
Posts: 1,028

For performance in the twisty's consider a wider tire 265 or 275. The smaller the O.D. the better the gear. I have the 2.73:1 but with my tires it's 2.86:1 .
audioAl is offline   Reply With Quote

Related Topics
Thread Thread Starter Forum Replies Last Post
Snow performance stage 2 MAF boos cooler install jwog666 Pipes, Boost & Juice 6 01-07-2018 08:16 AM
Chassis wiggle when off throttle? UrS4 S197 Handling Section 10 10-03-2015 07:23 AM
20 inch Wheels a mistake on 2015 Mustang GT? mungodrums The New S550 2015-2017 Mustang 10 09-28-2015 11:54 PM
Polished wheels folivier Detailing 0 09-26-2015 03:28 PM
2 or 4 wheel alignment? lincolnshibuya V6 (1994-2004) Mustangs 1 09-24-2015 11:46 PM

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Forum Jump

Featured Sponsors
Vendor Directory

All times are GMT -5. The time now is 08:18 AM.

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.