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Topic: Rear tire sizes (Read 115 times) previous topic - next topic

Rear tire sizes

Hey all, I thought this topic was beaten to death, but I can't seem to find the info any more since the site switch. Anyway, it's time for new tires on my bird and I think I may want to go wider. Have people ran 275/50r15s or 275/60r15s without rolling the fenders and retaining the quad shocks?

I can't decide between the 26" or the 28". I currently run 255/60r15s which are about 27. So if anyone has pics that would be very helpful.
1988 Thunderbird sport
2004 Ford F150 Lariat
2008  Chevrolet Cobalt Sport
2007 Suzuki DR-Z400S dual sport/Supermoto
1988 Thunderbird LX - sold
1988 Mercury Cougar XR-7 with GST kit - gone

Re: Rear tire sizes

Reply #1
Not that I will be much help but obviously you have 15" diameter wheels but what is the width, backspacing and offset?  If you are running a factory wheel let us know which one as someone may be running that same wheel and can chime in.

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp

Re: Rear tire sizes

Reply #2
When I had my Sport in it's final configuration, I had 275/40/17 on the back. No rolling, but the tires were fairly close IIRC. Quad shocks are a no-go unless you come up with some funky weird offset wheels, but then you'll tire protruding and probably other issues..

I had mine on Bullit wheels from something like an '03, '04 Mustang. The fit was perfect, too. Fronts were 245/45 and also fit well, no rubbing etc.

As an aside and not much relevance here, those same wheels/tires are now on my '87 Stang notch and unless I did body work, the combo is about as big as can be stuffed in there. One thing about The Tbirds...you can put a little more tire under it and have some wiggle room.
'84, '87 Mustangs
'98 Explorer 5.0
'06 Explorer EB 4.6
'11 Expedition EL

Re: Rear tire sizes

Reply #3
I can't answer your question exactly, but I have a 275/35/18 on an 18x9 +35mm wheel. There is plenty of clearance to the fender lip and about a half inch to the quad shock.


You can kinda see the clearance to the fender lip in that picture.
It's Gumby's fault.

Re: Rear tire sizes

Reply #4
Thanks guys. I am unsure of backspacing. I got the wheels used, so I would need to pull them and measure. I will say they appear pretty centered with about 3/4" between either the quads or the lip. Thanks for the pic Shawn. I think I may have enough clearance to pull it off.
1988 Thunderbird sport
2004 Ford F150 Lariat
2008  Chevrolet Cobalt Sport
2007 Suzuki DR-Z400S dual sport/Supermoto
1988 Thunderbird LX - sold
1988 Mercury Cougar XR-7 with GST kit - gone

 

Re: Rear tire sizes

Reply #5
Damn Shawn....with Bullitt wheels I couldn't run the quads LOL. And I would've, had they fit. I had a pair of fairly new ones.

I also had CHE arms, so losing the quads in my case wasn't much of an issue. Anyway...your TC looks good!
'84, '87 Mustangs
'98 Explorer 5.0
'06 Explorer EB 4.6
'11 Expedition EL

Re: Rear tire sizes

Reply #6
These wheels have an odd offset compared to what most people use on fox bodies.

Fox body Mustangs have far less room in the rear wheel wells, so they bring the tires in closer to the inner wheel well. If we ditch the quads and tail pipes, we can stuff a 10.5" wheel and a 315 in the rear.
It's Gumby's fault.

Re: Rear tire sizes

Reply #7
You're right on the Fox Stangs. Those tires of mine don't leave much room. Can't remember how little the gap is between the tire and shock on mine, but it ain't much.
I miss having a Tbird. Might have to start looking again...
'84, '87 Mustangs
'98 Explorer 5.0
'06 Explorer EB 4.6
'11 Expedition EL