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Old 01-11-2024, 05:14 AM
BIG BLOCK JAMO BIG BLOCK JAMO is offline
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Default 1970 Grand Prix Tire Sizes..

1970 Grand Prix Tire Sizes;
I'm restoring a 1970 SJ 455 Ho / 4-Speed LOADED, NO A/C, Silver/Black Leather
I have 4, 7" X 15" Rally II wheels.
What size tire combos do you recommend?
I Like to get a bigger tire on the rear.
What's the biggest tire I can put on the rear without rubbing?
Any comments or advice is much appreciated,
I posted this before but can't find my thread.
Thank you in advance..:
BIG BLOCK JAMO
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63 Catalina 421, Tri-Power, 4-Speed, w/ Console, Ventura Interior, 8 Bolts (Disc), Tach, Tilt, Deluxe Wheel, Power / Windows, Steering, Brakes
64 GTO 455, Tri-Power, 5-Speed, w/Console, 12 Bolt 3:42, 4 Wheel Disc, Tach, Tilt, 4 Spoke Wheel
66 2+2 Convertible 421, Tri Power, 4-Speed w/Console, 8 Bolt (Disc), P/Top,Windows, Steering, Brakes AM/FM,


Last edited by BIG BLOCK JAMO; 01-11-2024 at 05:22 AM.
  #2  
Old 01-13-2024, 11:24 AM
CanAmT/AGTO CanAmT/AGTO is offline
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Paul,

I am running 255 60 15's rear and 245 60 15's on front.
I do not have any rubbing while turning steering wheel lock to lock.
I would think there are many other configurations that work but wanted to give you some feedback.

Larry

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  #3  
Old 01-29-2024, 08:55 PM
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1970gpsj4speed 1970gpsj4speed is offline
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im running 275s on the back but im running 8 inch rims .I agree with post above 255/245
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  #4  
Old 02-02-2024, 08:40 PM
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Sprocket Sprocket is offline
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275/60-15 fits with ease and that is a 28" tall tire. A 295/50-15 ran close for me but okay. I have seen a '70 GTO with 305's, but do not know if a GP can get there.

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3.50 9" CurrieTrac, 245/45-18 Front, 275/40-18 Rear
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