Jump to content
HybridZ

18" Cobra Rims


Recommended Posts

Go to: http://flickr.com/photos/42511247@N00/?saved=1

 

18"x9" 1999 Mustang Cobra rims. 275-40 rear, 245-40 front. Just a trial fit right now cuz I still need to do a 5 lug conversion. Stock suspension with Tokicos all the way around. Close to the strut, but with creative spacing, looks like I could probably get away with som ZG flares, but I am leaning toward spacing them out a little more and going 280 YZ rear with Subtle Z front. What do ya think?

Link to comment
Share on other sites

  • 1 month later...

Torynich,

 

I too am trying to figure out what size wheels to fit on my 240z. I have already installed the 280 YZ and subtle Z fenders.

 

I am looking at 18x9 wheels with a low offset. Maybe +12 to +20. By my calculations that would require at least a 2" adapter.

 

What are the other specs on those Cobra wheels? What is the offset or rear backspace? What is the bolt pattern?

 

Maybe we can put our heads together and get each other's cars looking great!

 

http://web.mac.com/modernmagic/iWeb/240z

Link to comment
Share on other sites

I have 2" 4 lug to 5 lug adapters on it now (cheap and easy untill I can afford to do the full conversion to 5 lug) and the rears stick out about 1.5". I should be receiving my ZG flares today so we'll see how it looks with this set up. I will measure the backspace when I remove the wheels next, but I dont think stock 18X9 cobra rims will look right on a YZ flare. To get them out far enough you would have to go with an extremely thick spacer. Ask Rick Bowers what he did, his looks great.

Link to comment
Share on other sites

www.ezaccessory.com 4 lug 4.5" to 5 lug 4.5" 2" thick $129/pair Buy the lug nuts at the same time and save on shipping or you will be ordering them later after finding out what the auto parts stores are asking for them (I learn the hard way some times). They are pretty nice. i did have to enlarge the center hole on the fronts just a tad. I powdercoated them semi gloss black so they wouldnt stand out as much since you can see everything through these wheels.
Link to comment
Share on other sites

I'm using 10.5X17 Cobra wheels with 315/40-17 tires on the rear and IMHO, they are still too skinny for the YZ flares. I have the AZC 5-lug brakes which modify the rear offset about 3/4" outward from stock, and curently am using a 1-1/4" spacer on the rear. A 9" wheel would need a huge spacer to even come close to the wheel arch of the YZ rear.

 

My fronts are the same wheel with 275/40-17 and a 2" spacer - again too skinny for the YZ front fenders. Dunno about the Subtles - We have a YZ rear, Subtle front in the shop now - no front fenders installed as yet - I'll report the wheel specs when they are on - the owner is ordering custom pieces.

 

My Cobra wheels have 21 mm offset.

 

I have coilovers with shortened struts and 12" springs.

 

These wheels/tires are temporary until I get my 13/12 X18 CCWs with the correct offset to eliminate the spacers.

 

As I've said often, you MUST measure your own setup, as most will fit a different size wheel as dictated by flares, springs, struts, ride height, etc. - Very few of our cars are still stock. :mrgreen:

Link to comment
Share on other sites

Speeder, thanks for all the great info.

 

You are obviously correct in stating that all cars have different measurements. I measured the total clearance in the rear wheel well to be 12" with my YZ fenders installed. 12 x 25.4 = 305 max tire width. I plan on shooting for 275 so that I have 1/2" clearance front and back for suspension squirm.

 

Does this sound right?

 

For that matter here's my math for sizing the rear wheel and tires:

12.25" total clearance

7" front side

5.25" backside

275 tire width = 10.8"

10.8" / 2 = 5.4" centerline of wheel

5.4" + .5"(front side space between tire and fender) = 5.9"

7" - 5.9" = 1.1" offset

Assuming a +30 offset is common for a off the shelf wheel

30 / 25.4 = 1.18"

1.18 + 1.1 = 2.28" adapter required

 

Does this sound like the right math?

Link to comment
Share on other sites

My 10.5X17/ 315/35-17's (Street Setup) tire sidewalls are about 1/2" in from the inner surface of the fenderwell. Measured by dropping a plumb bob -

 

My roadrace tires, 305/35-18, on 10" Saleen replica rims, Have an almost exact same fit (The 18"Toyo RA-1s have a wide section width that makes up for the smaller size)

 

"But" my rear fender arches are radiused oversize to accommodate my other rear wheel/tire combo, a 28" tall 325/50-15 Drag Radial on 10X15s. These clear, by the way, with more than 3" of squat.

 

Like I said, They're all different! You MUST measure your own!

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...