Yes, another tire/wheel thread...but quick!
Thread Starter
Intermediate
Joined: Nov 2024
Posts: 38
Likes: 42
Yes, another tire/wheel thread...but quick!
I have spent a ton of time researching this board and have found a lot of great information, but as I think we all know there is almost too much. Here is the story, I am wrapping up a Mustang project and moving to a C3. I think I have found the one for me, but it still needs an inspection since it is out of state for me. Once that clears I will start a "journey" thread, but I can't now as I don't want to jinx it.
In short, it is a 72 with no body mods. I am going to put a Global West coil over front suspension & swaybar on it with the Ridetech rear coil over system. Of course wheels and tires need to be sorted and somehow the math on these decisions seems infinitely complex. I believe I have sorted it down to the following:
https://www.corvetteforum.com/forums...-and-19-a.html
From the information in that thread and the posts from @cagotzmann in particular, it seems like that front setup will work (I understand each car is different, but not sure how to work that calculus into this equation). As for the rear, @cagotzmann was running 18x9.5 in the rear but also posted a super helpful pic of the Ridetech system. To my eye it looks like 11 inch rims for the 305's will fit in there.
Thoughts/comments???
Thanks!
In short, it is a 72 with no body mods. I am going to put a Global West coil over front suspension & swaybar on it with the Ridetech rear coil over system. Of course wheels and tires need to be sorted and somehow the math on these decisions seems infinitely complex. I believe I have sorted it down to the following:
- Front: 265 40 r18x9.5 with 4.75" backspace
- Rear: 305 35 r18x11 with 6" backspace
https://www.corvetteforum.com/forums...-and-19-a.html
From the information in that thread and the posts from @cagotzmann in particular, it seems like that front setup will work (I understand each car is different, but not sure how to work that calculus into this equation). As for the rear, @cagotzmann was running 18x9.5 in the rear but also posted a super helpful pic of the Ridetech system. To my eye it looks like 11 inch rims for the 305's will fit in there.
Thoughts/comments???
Thanks!
Race Director
Joined: Jan 2007
Posts: 14,959
Likes: 3,353
From: NYC NY
With a stock frame I believe the frame rail is the limiting factor with an 18" wheel or larger diameter regardless of the rear suspension vendor.
The widest I have seen is 18X10.5 with 5.5 backspace and a 315/30-18 tire.
Hopefully others will post additional information.
The widest I have seen is 18X10.5 with 5.5 backspace and a 315/30-18 tire.
Hopefully others will post additional information.
Thread Starter
Intermediate
Joined: Nov 2024
Posts: 38
Likes: 42
Thanks for the insight 3Js. When I did my first round of research on the web, it indicated a 305 wouldn't fit on a 10.5" rim. However, after seeing your post I went back and it appears lots of people are running 305's on 10.5" rims, so it looks like that could work in my application.
Thread Starter
Intermediate
Joined: Nov 2024
Posts: 38
Likes: 42
OK - rethinking this a bit. Might have been a little too aggressive. This combo seems a bit safer for fitment, rub, etc:
- Front: 245/45 R18x8.5" with 4.5" backspace
- Rear: 285/40 R18x10" with 5.25" backspace
Drifting
Joined: Oct 2005
Posts: 1,528
Likes: 148
From: East London/SW Essex UK
With a stock frame I believe the frame rail is the limiting factor with an 18" wheel or larger diameter regardless of the rear suspension vendor.
The widest I have seen is 18X10.5 with 5.5 backspace and a 315/30-18 tire.
Hopefully others will post additional information.
The widest I have seen is 18X10.5 with 5.5 backspace and a 315/30-18 tire.
Hopefully others will post additional information.
Instructor
Joined: Jun 2023
Posts: 178
Likes: 75
From: California
I've got 275/40R18 on 18x10.5 rims on all 4 corners of my 82.
Front: -11mm offset, 5.32" (135.1mm) BS
Rear: -8mm offset, 5.44" (138.1mm) BS
Stock trailing arms clear with the e brake relocated. Like others have said, the frame is the limiting factor. My rears kiss the frame and sway bar in hard corners, but not as much as they did with 9.5" wide rims. I don't see how anything more than maybe 5.5" BS in the rear is possible.
To say these tires are "flush" would be pushing it, but somehow they still manage to tuck under the stock fenders even though they don't look like they would.
Front: -11mm offset, 5.32" (135.1mm) BS
Rear: -8mm offset, 5.44" (138.1mm) BS
Stock trailing arms clear with the e brake relocated. Like others have said, the frame is the limiting factor. My rears kiss the frame and sway bar in hard corners, but not as much as they did with 9.5" wide rims. I don't see how anything more than maybe 5.5" BS in the rear is possible.
To say these tires are "flush" would be pushing it, but somehow they still manage to tuck under the stock fenders even though they don't look like they would.
