18” Wheels 1969 Camaro Help - Team Camaro Tech
Wheels & Tires What fits what?

 2Likes
Reply
 
LinkBack Thread Tools Display Modes
post #1 of 23 (permalink) Old Apr 12th, 18, 06:29 PM Thread Starter
Apprentice
Jordan
 
Join Date: Mar 2013
Location: United States
Posts: 20
18” Wheels 1969 Camaro Help

I have a 1969 Camaro lowered 2 inches in the front and back. I have purchased firestone firehawk 275/40r18 tires for the rear and 245/40r18 for the front. My wheels I had purchased were US Mags Rambler 18x8 with 4.5 backspacing +1.00mm offset on the front. 18x9.5 with 5.250 backspacing with +1.00mm offset. Ran into some issues today… The back wheels are going to rub the quarter panels and front wheels are going to rub the front fenders. Some proper info on backspacing and offset needed. I have disk brakes front and rear. Any information is helpful.
jrdnduvall is offline  
Sponsored Links
Advertisement
 
post #2 of 23 (permalink) Old Apr 12th, 18, 07:26 PM
Gold Lifetime Member
Chris
 
Join Date: Oct 2013
Location: Texas
Posts: 1,021
Re: 18” Wheels 1969 Camaro Help

If you're only missing clearance by a smidge, you could roll the fender inner lip to gain clearance.

'69 Z/28, Lemans Blue/White Stripes, DZ302, Tremec Magnum, 4.10, Procar Elite Seats,
Custom Upholstery, Dynatech headers, 17" VWW V45's, 235/45, 275/40, C5 Front Brakes
ctcz28 is offline  
post #3 of 23 (permalink) Old Apr 12th, 18, 07:38 PM
Team Member
Don
 
Join Date: Jun 2006
Location: Mountain Springs, Texas
Posts: 3,458
Re: 18” Wheels 1969 Camaro Help

Add some negative camber and the fronts will likely be ok. Try -.5 degrees.

Trimming the rear lip at the 10 and 2 o’clock positions usually helps.

Don

1969 Camaro LSA 6L90E AME subframe and IRS
1969 Camaro vert LS3 4L65E Ridetech level 2 - sold
1959 El Camino project
1969 Mustang Sportsroof project
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

1956 Cameo project - C5 drivetrain
1957 Buick Caballero project
dhutton is offline  
 
post #4 of 23 (permalink) Old Apr 12th, 18, 07:40 PM Thread Starter
Apprentice
Jordan
 
Join Date: Mar 2013
Location: United States
Posts: 20
Re: 18” Wheels 1969 Camaro Help

I suggested that to the body shop and they steered me away from that. Going to need new wheels anyway as the others were ruined by the tire shop, but that’s a story for another day… Any info on correct backspace and sizing?
jrdnduvall is offline  
post #5 of 23 (permalink) Old Apr 13th, 18, 05:17 AM
Senior Tech
Bill
 
Join Date: May 2004
Location: connecticut
Posts: 587
Re: 18” Wheels 1969 Camaro Help

every vehicle is a little different so everyone's specs do not always work out for you, ask me how I know. I had to change tire size , the tire shop went to test fit , they would not fit and charged me a small fee to change tires to a smaller size before driving on them.
bills69 is offline  
post #6 of 23 (permalink) Old Apr 13th, 18, 05:43 AM
Team Member
Don
 
Join Date: Jun 2006
Location: Mountain Springs, Texas
Posts: 3,458
Re: 18” Wheels 1969 Camaro Help

+6mm offset front and rear assuming your disc brakes have not affected it. Use the wheels you already have to confirm this. Camber plays an important role on front tire fit. You need to know what camber you have when doing your test fitting.

Relying on a body shop to optimize wheel and tire fit is a little odd imho....

1969 Camaro LSA 6L90E AME subframe and IRS
1969 Camaro vert LS3 4L65E Ridetech level 2 - sold
1959 El Camino project
1969 Mustang Sportsroof project
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

1956 Cameo project - C5 drivetrain
1957 Buick Caballero project
dhutton is offline  
post #7 of 23 (permalink) Old Apr 13th, 18, 06:54 AM
Moderator
John
 
Vega$69's Avatar
 
Join Date: Sep 2010
Location: Vegas NV/Wesley Chapel FL
Posts: 12,220
Garage
Re: 18” Wheels 1969 Camaro Help

to correctly determine wheel spec you have to start with the tire. Section width and tread width.

You can also start by installing a wheel with a known/measured BS without the tire mounted. Jack stand under the axle and take relative comparison measurements with straight edge clamp to the wheel.

When it's close go with slightly more then calculated BS. You can always ad an 1/8" or 1/4" spacer to move the wheel outward.

66 Chevelle Protour LS3/525(SOLD AT Mecum 2018)
69 SS396 Cortez Silver(SOLD)
69 Z28(Sold)
69 Pro Tour - LS3/T56
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
(SOLD)
69 Pro Tour - LS7/T56 (SOLD)
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

69 Z28/RS Tribute355/5 Speed (SOLD)
69 RS Clone 427/TH400 (SOLD)
67 RSZZ502/5 Speed (SOLD)
69 Camaro 406 SBC/TH400 (SOLD)
Vega$69 is offline  
post #8 of 23 (permalink) Old Apr 13th, 18, 07:24 AM
Senior Tech
Simon
 
Join Date: Jul 2009
Location: Toronto, Canada
Posts: 472
Garage
Re: 18” Wheels 1969 Camaro Help

I went with 235/40/18 in the fronts, try button head bolts to help gain clearance. Also have the shop put one of the front wheels with the tire mounted on the back and take the critical measurements before purchasing and mounting the rest. If I'm not mistaken my shop had to reverse mount the tires onto the rims.
slazisme is offline  
post #9 of 23 (permalink) Old Apr 13th, 18, 10:18 AM
Team Member
Don
 
Join Date: Jun 2006
Location: Mountain Springs, Texas
Posts: 3,458
Re: 18” Wheels 1969 Camaro Help

+6mm offset keeps the wheel centered in the opening regardless of width....

Don

1969 Camaro LSA 6L90E AME subframe and IRS
1969 Camaro vert LS3 4L65E Ridetech level 2 - sold
1959 El Camino project
1969 Mustang Sportsroof project
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

1956 Cameo project - C5 drivetrain
1957 Buick Caballero project
dhutton is offline  
post #10 of 23 (permalink) Old Apr 13th, 18, 11:14 AM
Tech Team
Robert
 
Join Date: Nov 2013
Location: maryland, US
Posts: 83
Re: 18” Wheels 1969 Camaro Help

I have Budnik Vapor wheels. Charcoal Grey centers with polished rims.
18x8 5" BS - 245/45-18
18x9 5.375" BS - 275/40-18

My car is lowered 1.5" in the rear, the front is probably 2 inches down from sagging springs. I have new 2" drop springs to install soon.
Both front and back fit without modifying the lips, I have about 1/2" clearance. BUT, I do have slight rubbing on the frame in the rear going over bumps going around a corner at low speed and I cannot turn as sharp. The turning issue might be straightened out once I install RideTech upper control arms and get a good alignment, we will see. I have pictures here:
https://www.camaros.net/forums/33-cam...s-evening.html
Cunning69 is offline  
post #11 of 23 (permalink) Old Apr 13th, 18, 06:36 PM
Gold Lifetime Member
Beth
 
Join Date: Mar 2018
Location: Nashville TN
Posts: 504
Re: 18” Wheels 1969 Camaro Help

As Don said, 6mm puts you in the center.

On an 8" wheel, add 1" to get the outer width, divide by 2 to get the center.
8"+1"= 9"/2= 4.5" + 6mm (1/4") offset to the inside = 4.75" ideal backspace for an 8" rim

I bought 4.5" backspace wheels for my car because they are easier to find and I wasn't trying to squeeze in the largest possible tire.
NashvilleCat is offline  
post #12 of 23 (permalink) Old Apr 15th, 18, 04:19 PM Thread Starter
Apprentice
Jordan
 
Join Date: Mar 2013
Location: United States
Posts: 20
Re: 18” Wheels 1969 Camaro Help

Here's my plan after some measuring. Im going to buy U425 Rambler wheels from US Mags. They are customizable. In the rear I'm going to go with a 18x9 wheel with 5.75 backspace. For the front I'm going to go with a 18x8 with a 5.50 offset. Does this seem like too much backspacing for the front? I'm erring on the side of too much as I could add a spacer if needed. I appreciate everyones advice thus far.
jrdnduvall is offline  
post #13 of 23 (permalink) Old Apr 15th, 18, 04:38 PM
Team Member
Don
 
Join Date: Jun 2006
Location: Mountain Springs, Texas
Posts: 3,458
Re: 18” Wheels 1969 Camaro Help

Quote:
Originally Posted by jrdnduvall View Post
Here's my plan after some measuring. Im going to buy U425 Rambler wheels from US Mags. They are customizable. In the rear I'm going to go with a 18x9 wheel with 5.75 backspace. For the front I'm going to go with a 18x8 with a 5.50 offset. Does this seem like too much backspacing for the front? I'm erring on the side of too much as I could add a spacer if needed. I appreciate everyones advice thus far.
Your spacers may be so thick that the wheel studs are not long enough. 5.5 offset or backspacing?

+6mm offset centers the wheel. Translate this to backspacing for a given wheel width using this tool:

https://rimsntires.com/specspro.jsp

Don

1969 Camaro LSA 6L90E AME subframe and IRS
1969 Camaro vert LS3 4L65E Ridetech level 2 - sold
1959 El Camino project
1969 Mustang Sportsroof project
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

1956 Cameo project - C5 drivetrain
1957 Buick Caballero project
dhutton is offline  
post #14 of 23 (permalink) Old Apr 15th, 18, 05:46 PM Thread Starter
Apprentice
Jordan
 
Join Date: Mar 2013
Location: United States
Posts: 20
Re: 18” Wheels 1969 Camaro Help

Attached are my results with a 6mm offset. The original wheel is the one I had before vs the one I'm thinking of ordering. The result is a bit confusing to me. Just have a hard time understanding all this.
Attached Thumbnails
Click image for larger version

Name:	IMG_1099.jpg
Views:	103
Size:	71.2 KB
ID:	211833   Click image for larger version

Name:	IMG_1100.jpg
Views:	66
Size:	75.7 KB
ID:	211841  
jrdnduvall is offline  
post #15 of 23 (permalink) Old Apr 15th, 18, 06:12 PM
Team Member
Don
 
Join Date: Jun 2006
Location: Mountain Springs, Texas
Posts: 3,458
Re: 18” Wheels 1969 Camaro Help

Yep, you needed another .25” of backspacing with your original wheels. That is why I suggested trimming the rear wheel lips and adding negative camber on the front.

Offset is measured relative to the center of the wheel so it is independent of wheel width.

A 275 tire will likely rub under some conditions no matter what you do but it is minimal and most who want to run a 275 tire choose to live with it. Usually when approaching a steep driveway at an angle.

Don

1969 Camaro LSA 6L90E AME subframe and IRS
1969 Camaro vert LS3 4L65E Ridetech level 2 - sold
1959 El Camino project
1969 Mustang Sportsroof project
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

1956 Cameo project - C5 drivetrain
1957 Buick Caballero project
dhutton is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Team Camaro Tech forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address.
NOTE we receive a lot of registrations with bad email addresses. IF you do not receive your confirmation email you will not be able to post. contact support and we will try and help.
Be sure you enter a valid email address and check your spam folder as well.



Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may 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 On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome