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  #1  
Old 06-18-2026, 06:48 PM
Ramairformula Ramairformula is offline
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Default New tires

Hi All,
My 74 Formula 400 needs new skins, currently on TA 235/60/15s on Honeycombs, looking at going to 255/60/15s but hard to find here, Vancouver Island, B.C., one shop suggested 255/70/15s, but are they too big? 29" tall and would they rub and/or look kind of weird? Thanks in advance for your feedback.
Cheers, Peter

  #2  
Old 06-18-2026, 07:05 PM
67Lemons 67Lemons is offline
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Cooper Cobra’s should be easy to get in that size, I’m running 255/60R15’s in the rear.
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Old 06-18-2026, 07:12 PM
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Skip Fix Skip Fix is offline
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Ran 255-60-15s all the way around my 78.Herb Adams that was his go to tire back 70s 80 for handling before 16" came out. 235 70 about the tallest tu use unless you go 275-60-15 in rear

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Old 06-18-2026, 07:58 PM
Steve C. Steve C. is offline
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275 /60R15 Nitto 555 Drag Radial on the rear here.
27.76" dia / overall width 11.1"

This based on personal experience and offered here for general interest only as the suspension set up will differ.
Firestone Indy 500 235/60-15 on the front pictured. But I have switched to Cooper Cobra 245/60-15 in the front.

https://hips.hearstapps.com/mtg-prod...75&format=webp

https://hips.hearstapps.com/mtg-prod...75&format=webp



.

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'70 TA / 505 cid / same engine but revised ( previous best 10.63 at 127.05 )
Old information here:
http://www.hotrod.com/articles/0712p...tiac-trans-am/

Sponsor of the world's fastest Pontiac powered Ford Fairmont (engine)
Best time 5.13 at 140 mph (1/8 mile) , true 10.5 tire, stock type suspension
https://www.youtube.com/watch?v=qDoJnIP3HgE
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Old 06-18-2026, 10:22 PM
jerry455 jerry455 is offline
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I have BFG 255 60 15 on some repo 8" snowflakes on my 1976 Firebird. They look and fit nice.

  #6  
Old 06-19-2026, 03:10 AM
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65madgoat 65madgoat is offline
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For 1973+ F body cars at stock height, the 225/70-15 is an ideal size to get. Go for it. Trust me.

It is actually just over a 27" tall tire.

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Old 06-19-2026, 08:19 AM
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255 all around on 15 x 7 rally II on my 74 for the street

275 back , 255 front on 15 x 8 aftermarket on my 75
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461 stroker
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75 Formula 400 / 4-SPD matching numbers
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Old 06-19-2026, 08:27 AM
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The Champ The Champ is offline
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Quote:
Originally Posted by Ramairformula View Post
Hi All,
My 74 Formula 400 needs new skins, currently on TA 235/60/15s on Honeycombs, looking at going to 255/60/15s but hard to find here, Vancouver Island, B.C., one shop suggested 255/70/15s, but are they too big? 29" tall and would they rub and/or look kind of weird? Thanks in advance for your feedback.
Cheers, Peter
255/60/15 BFG TA's are in stock at Canadian Tire system.

  #9  
Old 06-19-2026, 10:41 AM
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kingbuzzo kingbuzzo is offline
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I just swapped my wheels to 15" honeys and went with bfg 255 60's front and 275/60s rear.

I'm basically stock height and the 275's actually "fixed" my saggy arse somewhat which was a surprise.

So far they look great but I'm getting slight rubbing at the rear in hard cornering so I need so do some "modifications" out back. Huge traction upgrade off the line which was also a surprise.

And yes, the 275's were almost impossible to find in Manitobia but got lucky as the local gm dealer was able to find a pair.

Good luck.

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  #10  
Old 06-19-2026, 02:55 PM
Ramairformula Ramairformula is offline
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Thank you everyone for your replies!
I tried numerous tire dealers in Canada and could only come up with 2 tires in the country, so I went with Cooper Cobra's 255/60/15's, getting installed this afternoon. Even those were not an easy find, but one warehouse had 5.
Thanks again, you guys rock! Kind regards, Pete.

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  #11  
Old 06-20-2026, 07:36 AM
67Lemons 67Lemons is offline
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While I haven’t had a set of TA’s in a long time I think you’ll like the Cobra’s, most folks agree that they are a better tire than the TA’s (especially for the money) and as an added benefit they don’t brown out like the TA’s.

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  #12  
Old 06-20-2026, 02:02 PM
Steve C. Steve C. is offline
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A fwiw tid bit....

At one time it was reported Mickey Thompson Sportsman S/T tires were made by Cooper.
Having purchased and used both I can say, although similar, they have a slightly different tread pattern.

https://www.mickeythompsontires.com/.../sportsman-s-t


.

__________________
'70 TA / 505 cid / same engine but revised ( previous best 10.63 at 127.05 )
Old information here:
http://www.hotrod.com/articles/0712p...tiac-trans-am/

Sponsor of the world's fastest Pontiac powered Ford Fairmont (engine)
Best time 5.13 at 140 mph (1/8 mile) , true 10.5 tire, stock type suspension
https://www.youtube.com/watch?v=qDoJnIP3HgE
  #13  
Old 06-20-2026, 05:05 PM
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P@blo P@blo is offline
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The BF Radial TA tires are a terrible tire. Like rolling around on four bouncy houses and takes the Am out of Trans-Am to put it nicely. 256-60R15 Cooper Cobra all the way around on both my Firebirds and like them a lot more.

Also, the tire places like to sell you smaller tires for the front. Well the unmatched sizes will reduce your warrany by half if you read it before deciding.

  #14  
Old 06-20-2026, 05:38 PM
Steve C. Steve C. is offline
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From the internet.....

"...the Cooper Cobra Radial G/T often outperforms the BFGoodrich Radial T/A in lateral g skid pad testing. Coopers generally yield sharper dry handling, quicker turn-in response, and a slightly higher level of all-season grip than the classic BFG "

"Comparing the Cooper Cobra Radial GT and the Mickey Thompson Sportsman S/T is largely an exercise in brand preference, as Cooper Tire is the parent company that manufactures both. In the 15-inch street cruiser and muscle car segment, they share similar design DNA, but subtle differences exist in pricing and tread"


.

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'70 TA / 505 cid / same engine but revised ( previous best 10.63 at 127.05 )
Old information here:
http://www.hotrod.com/articles/0712p...tiac-trans-am/

Sponsor of the world's fastest Pontiac powered Ford Fairmont (engine)
Best time 5.13 at 140 mph (1/8 mile) , true 10.5 tire, stock type suspension
https://www.youtube.com/watch?v=qDoJnIP3HgE
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