Posts: 43
Threads: 7
Joined: Aug 2019
Hello everyone.
I need to get some confirmation that the wheel change I am planning on doing will work.
These will be going on my 69 Mach 1 428 CJ.
Currently on the car are P235/60R14 front and rear.
I want to change to 15” x 7” - 235/60R15 front and 15” x 8” - 255/60R15 rear.
Just want to make sure I don’t need any special offset or anything else.
Thanks, Tom.
Posts: 3,119
Threads: 92
Joined: Jan 2010
Oh yes you will! I don't believe there is any way, your gonna stuff that much tire under the rear of a 69. Without some very careful measuring etc. It can be done, and I believe there is a tire calculator on the site somewhere. Do a search, and see if you can't find one. Some of the other guy's will chime in soon, and may be of more help. I had a 71, and L60's on 15 inch rims got into my rear fenders bad enough I had to cut them. I just don't know for sure about the 69's. Good Luck
JTS
Posts: 3,119
Threads: 92
Joined: Jan 2010
http://tire-size-conversion.com/tire-size-calculator/
I just found this in an old thread, hope it helps.
JTS
Posts: 4,181
Threads: 46
Joined: Jan 2011
Hey Tom,
Sorry I do not have the answer for you - BUT that is a great post to start!
We do have a similar post "My rear tires are rubbing"
https://mach1club.com/showthread.php?tid...=tire+size or this thread "What wheels are you running on your Mach 1"
https://mach1club.com/showthread.php?tid...=tire+size
We need to have it broken down into years - as what fits and what hits really differs between the years!
Your wheel backspacing will also determine how wide you can go. Usually there is a lot of width "left on the table" behind the tire.
Help us out by letting us know what you find out!
Posts: 43
Threads: 7
Joined: Aug 2019
Thanks for the responses. I have gone to a couple of the sites with the links but they seemed unclear to me. CJP has a set of Magnum 500's with the tires that i was looking at but no disclaimer that they might not fit. I'll keep checking. I was hoping someone on here had already tried it.
Thanks, Tom.
Posts: 43
Threads: 7
Joined: Aug 2019
Just did the tire calculator and there is very little difference in the physical size of the proposed tires compared to the existing. For the front the only difference is 1" more in the overall diameter and in the rear the only difference is 1.9" in overall diameter and .9" in tire width. There appears to be tons of room in my wheel wells to put on the new sizes. Right now it looks like I have 12" wheels on it.
Tried to post the calculations but it didn't work.
Posts: 3,119
Threads: 92
Joined: Jan 2010
Some pictures might help us see where you're at? Oh by the way we like Pics.
JTS
Posts: 43
Threads: 7
Joined: Aug 2019
(09-25-2021, 08:37 AM)JTS71 Mach1 Wrote: Some pictures might help us see where you're at? Oh by the way we like Pics.
JTS
I’m trying to add pictures but it’s not working. I don’t have any close up pics right now but will tomorrow. Just have to figure out how to upload them. I always have problems with uploading pics I have taken with my iPad or iPhone.
Posts: 3,119
Threads: 92
Joined: Jan 2010
I do know most pics are to large, and need downsizing before the forum will accept them. I thought they had updated the site, but maybe not? Try downsizing them, and see if that helps.
JTS
Posts: 4,181
Threads: 46
Joined: Jan 2011
Yes, that is what I am battling with myself - loading pictures as I now use both an Apple phone and computer.
I ended up loading the pictures to the site using my phone as I still haven't figured out how to do it on the computer. My phone allowed me to change size format before loading them but I am not sure why it turned the one sideways!
Here's hoping you get it all figured out and get the pictures uploaded!