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Please help me pick the right tire size for my 78 Magnum XE

Magnum XE

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I have a 1978 Dodge Magnum which has been stored for over 40 years in the garage. I even posted it on my very own barn find. The current tires on the vehicle are GR 78 15s WSW. I would like to add BF Goodrich white lettered TA's when I've called support comparison Tire to that is a p225 70 R15. Does anyone have a similar car to that whether it is a Charger or a Cordoba which would be basically the same car if they have fitted p245 60 r15 on their car. I like a little beefier profile and this is the tire I like to add on the stock 15x7 rim I'll even enclose a photo of my current rims with the trim rings.

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245 Is about the biggest I would run on a 7"rim. And they will be a bit shorter than the 78 series you have now.
I think they will probably fit, but I have no way of knowing, never owned a Cordoba/Magnum/Charger.
And at about $40/tire cheaper, I would 100% buy Cooper Cobras long before I'd buy T/As. Better tire, less money!
 
245 Is about the biggest I would run on a 7"rim. And they will be a bit shorter than the 78 series you have now.
I think they will probably fit, but I have no way of knowing, never owned a Cordoba/Magnum/Charger.
And at about $40/tire cheaper, I would 100% buy Cooper Cobras long before I'd buy T/As. Better tire, less money!
What he said, and yes they will fit, and agree on the Coopers. ( Not sure about your wheel width pictured, are you sure they're 7" ? I don't recall. I thought the factory G60 tires were equipped with 7" wheels. )
 
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Agree with WileE. Best make sure those are sevens. If sixes, 225-235 would be a better choice. (You can make sure/measure without pulling a tire off).
 
Looks like 7 inch width as per brochure.

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P245/60R15 is fine with the OP's 7" wheel. Also, they will fit fine in the wheel wells of his Magnum.
 
I can't believe how wonderful and helpful everybody is . It's like having that friendly Neighbor Next Door!!
I did not expect a quick response like I got on my post. I did check the rims it's definitely a 7 in wide rim. I personally want to go with the 235s a friend of mine is telling me I'm nuts I should go and what 245 as it'll give it a beefier look. Either tire is still going to be better than the scrawny 46 year old tires I have on the vehicle now. LOL.. My dilemma is at 235s will fill the wheel well slightly better and the 245s will be slightly beefier stance. I'm leaning more towards the beefier stance after my friend has convinced me to do so. There is not a lot of information about adding a 245 most of the Tire websites say 225 70 15 is the biggest I can go. I was a little worried about the 245s rubbing on the inside of the wheels but I think I'll be okay. Tire crazy and Confused! I like the look of the BF Goodrich, the problem with that is they say that the white letters bleed out I don't mind paying the extra few dollars my car will not be driven a lot and going with the bf's over the Coopers.

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My 77 Cordoba had the heavy duty suspension and tow package. But the rims were 6.5 rims, not 7.
6 was standard. My car specified either G78 orG70 15 tires, they were steel wheels with wires though, not Rally or sport wheels. They could be different.
 
I can't believe how wonderful and helpful everybody is . It's like having that friendly Neighbor Next Door!!
I did not expect a quick response like I got on my post. I did check the rims it's definitely a 7 in wide rim. I personally want to go with the 235s a friend of mine is telling me I'm nuts I should go and what 245 as it'll give it a beefier look. Either tire is still going to be better than the scrawny 46 year old tires I have on the vehicle now. LOL.. My dilemma is at 235s will fill the wheel well slightly better and the 245s will be slightly beefier stance. I'm leaning more towards the beefier stance after my friend has convinced me to do so. There is not a lot of information about adding a 245 most of the Tire websites say 225 70 15 is the biggest I can go. I was a little worried about the 245s rubbing on the inside of the wheels but I think I'll be okay. Tire crazy and Confused! I like the look of the BF Goodrich, the problem with that is they say that the white letters bleed out I don't mind paying the extra few dollars my car will not be driven a lot and going with the bf's over the Coopers.

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You could play around with this calculator for different tire sizes and see what it recommends for wheel width.

https://www.1010tires.com/Tools/Tire-Size-Calculator/235-60R15


Your 7" wide rims look like a happy medium for P235R60-15 tires.

Go with what you want.
 
Interesting. I'm going strictly on memory from back in the day, but I don't recall G78 tires on 7" wheels from the factory. We did wheel/tire swaps up the wazoo, so details get blurred.
I am the original owner of this vehicle and it was parked in the garage after about one years of driving and then I got a company car to drive. In the photo I'm not sure if it'll come out clear you can see their GR 78 15s polyglass tires and these are the original tires that came from the factory on the car. The car has only 22,000 km which is approximately 12 to 13,000 miles. I have some detailed photos I posted on my original barn find. LOL. This car was literally parked after years driving I ran the tank dry and left it. I have a ton of work that is being done to the car right now to get on the road of course the brakes were all seized up, my friends are doing a complete brake job on the car and you lines calipers and wheel cylinders brake shoes problems rotors, the radiator was leaking and full of white crud , change the water pump. Believe it or not my tires are all rotted out. LOL...

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My vote is for a 245/60 for the rear and a 215/65 for the front.

That's what I have on the Plymouth.
8" width on the rear 7" on the front.

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back in the day i had a 79 chysler 300 i put 245 60 15 goodyear wingfoots on the front and 265 15 on the back no problems
 
Back when I was a tire store manager, we had a common tire package for the A-body (colonnade body) GM models of 255/60/15 on the factory 15x7 wheel, which was the minimum width wheel that the tire could (officially) handle and kept the heigth closer to the 27.5" that the factory came with. Many of those model's more aggressive packages (442, GS, SS, Le Mans sport/GTO) had 7" wheels stock and came with G60/15 tires too. As the B-Body is similar in stance/size, I would recommend the same, but any tire shop should allow you to "test" mount one on a rim, bolt it to one of the front hubs, let it down, and turn from lock to lock while bouncing the suspension to check for interference. It will fit all day on the rear, so if it clears on the front, send it. If the 255/60/15's don't appear to fit, I would recommend the 225/70/15 instead. Good luck either way and post pics once you have new shoes on your ride.
 
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