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Old 06-06-2020, 12:51 AM
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Default What is the most tire that can be run on the rear of a '73 LeMans?

Time for new tires, my car is running on stock size 14" and I want to change to 15" and something that fills the wheel wells better and can handle the torque of the Canadian Rat under the hood. . I was thinking about going 235 or 245 front and wonder if a rear stagger to 275 is possible with OEM style 15" wheels. What has been the collective experience of the Colonade Community on upgrading tires and wheel sizes?

Attached is a photo of my car as it currently sits on 215x70x14 which would be close to the F70x14 the car came with.
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  #2  
Old 06-06-2020, 02:19 AM
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Yeah, never dug the factory wheel and tire width. Always made the poor car look like an elephant on stilts. Great looking car you have there btw, but those 14s in the rear do look like they are begging for some relief.

The factory rim width will be your limiting factor. On the 15" rim, what is that - 7" I think? You'd be pushing 275 on a 9.5" wheel, so that's at least where you'd want to start IMO. You could probably get away with a 245 if it was an 8.5" rim.

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Old 06-12-2020, 12:26 PM
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Thanks '73LeMans for your input. I was really hoping for a better response,

Maybe my question should be What tire size are you running on your 73 LeMans?

Hope this gets me some much needed input.

Many thanks,

Ray

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Old 06-12-2020, 01:40 PM
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Keith Seymore Keith Seymore is offline
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I used run a 10" wide slick on a Corvette rally (15x8) on my '74 Chevelle.

The frame is the limiting factor. Massage the rail a bit and you can put a 13.5" wide tire on there with no changes to the wheelhouse.

The ones in the photos below are 11.5" on a 10" wide rim.

K



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Last edited by Keith Seymore; 06-12-2020 at 02:02 PM.
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Old 06-12-2020, 02:18 PM
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Man o man, that Chevelle sits perfect.

I'm running a 325/50/15, on a 10" rim. It makes my tires about 12.5" wide. I can still fit a bunch of fingers between the frame and the tire as you can hopefully see in this shot. (space, not fingers)



The frame is not my personal concern. Its the stupid tailpipes that are in my way from getting any wider. If i dumped the exhaust after the muffler, I see no reason why a larger tire can't be made to fit.

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Who needs nice and pretty, when you can have mean and nasty?
KRE Aluminum headed 463CID 73 LeMans. Used to run 10.6x @ 124.55. 3700lbs
.
2020 brings all new systems, and almost all new engine.
Swinging for 9s.
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Old 06-12-2020, 03:55 PM
PurelyGTO68 PurelyGTO68 is offline
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We run 275 tires on our 73 LeMans 400 with original 15" rally II wheels.

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Old 06-12-2020, 04:37 PM
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Thanks fellas, this is all good information and is what I was looking for, much appreciated.
I'd agree on Keith's Chevelle, the car looks amazing !

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Old 06-12-2020, 07:22 PM
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Back in the seventies the GA had 10" rims with L-50s. Rolled the wheel lip and tires didnt rub. Now I see it in Toronto with 15" rallies. Tire size unknown
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  #9  
Old 06-18-2020, 12:12 PM
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Default 245/60/15 BFGs

is what I run on my 74 Lemans and it does touch the muffler in rear and shines up the tie rod in the front, but works great. That's the biggest without any mods you can run.

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Old 06-20-2020, 07:47 AM
cdrookie cdrookie is offline
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Quote:
Originally Posted by moontower69 View Post
is what I run on my 74 Lemans and it does touch the muffler in rear and shines up the tie rod in the front, but works great. That's the biggest without any mods you can run.

I ran 325/50-15 on the rear and 275/60-15 on the front on 15x10 and 15x8 wheels. Your wheel backspace is wrong if you're rubbing.

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Old 06-27-2020, 01:23 PM
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After all this good input and test fitting wheels and tires I have ordered Radial T/As 255x60x15 rear with 15x8 wheels and 235x60x15 front with 15x7 wheels. 4.25 backspacing. Here's some pictures, once the project is done I will post more.
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Old 06-27-2020, 08:24 PM
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Thats going to look real nice!!!

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Mark S
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Who needs nice and pretty, when you can have mean and nasty?
KRE Aluminum headed 463CID 73 LeMans. Used to run 10.6x @ 124.55. 3700lbs
.
2020 brings all new systems, and almost all new engine.
Swinging for 9s.
  #13  
Old 06-30-2020, 12:09 PM
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Default I run 255/60/15 on Rally IIs

With no mods on stock springs and shocks, slightly touches exhaust and front sway bar on tight turn but no issues. Drives great, very planted. That's the biggest I've been able to get on 15x7 Rallys - can go bigger with 15x8 which WHEEL VINTIQUE makes
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  #14  
Old 07-02-2020, 12:16 AM
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Received this photo on my Instagram feed today. Don't know tire size but in terms of look this car has just the right amount of Badassery that I'm looking for.
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Old 07-02-2020, 09:39 AM
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IMO that car does have the look, but could look more badasser. It's hard to tell without a straight side shot but I'd drop the front a few inches and the back an inch or so. I'd put 10" wheels on the back with taller wider tires. I'm guessing those are 7" wide factory wheels and probably 70 series tires. The wheel wells on these cars are HUGE and need to be filled up to look correct. I'd love to put some MT 315/60-15 meats on the back of my Lemons. Even though they are DOT approved I'm not sure how much street use they'd handle.

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Old 07-02-2020, 11:02 AM
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Default BFG 275 60R/15 on back and 235/60/15 on front

That's a bad ass look if you can fit the rears on a custom rim....

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Old Yesterday, 12:41 AM
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Do you like pictures of progress on the project?

Used Duplicolor GM Royal Blue to get a good match of the paint for the wheels then Armstrong'd the tires on the wheels tonight, have to take them to a shop for balancing. Getting closer.
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