front tire diameter

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Ottmundr

Ottmundr

68 Fastback
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68 fastback
small bolt pattern
going from 14x7 all around to 15x7 front this paycheck and 15x7 or 15x8 next paycheck.
old wheels are 3.25" backspace, new are 3.75" for the 15x7, and the 15x8 are 4.5" backspace.

I'm upgrading to 15" wheels, and I'm looking for information on front tire diameters. After all I've read about how BF Goodrich T/A radials are sticky as a lubed proctologist's finger, I decided not to bend over for that ride.

I almost pulled the trigger on some Mickey Thompson Sportsman S/T tires so I'd have matching front and back. Then I noticed the tire diameter of 215/70/15 came out to 26.85. Will that diameter fit without rubbing when turning or going over bumps etc?

Thanks for the help! :burnout:
 
215/70R15 might be a problem, on my Dart Sport my fronts are 205/70R15's, I am thinking maybe one size smaller depending on the ride height of the vehicle. I imagine that maybe a 205/60 might work too.
 
I run 26's and have room. I doubt less than a 1/2" radius would change much.
 

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It's going to come down to the wheel "offset". When I installed 73/74 disc brakes on my '69 Barracuda I went with different wheels and tires because the disc brake swap changes the front wheel width (position). I wanted the tallest tire I could get in the wheel well so as a solution I went to down to the tire store and asked the tire guy,
"If I buy and pay for a pair of tires would you mount them (no balance) and let me take them home to test fit on my car and if they're too tall or too short can I bring them back for a different size??". The guy told me that is was no problem as long as I didn't run the tires on the road. I told him that I would only lower the car to the ground to see how much clearance I had from the front fender. He agreed!! It took me two tries to get it right. I can tell you what size tire I ended up with but I don't remember the rim offset, my offset wouldn't help you anyway unless you have the same disc brake set up.
So....your tire diameter (and width) is directly related to wheel offset when it comes to front fender clearance. Unless someone has the exact same set up as your car you might have to experiment like I did. Even front end height makes some difference because the higher your car is raised the more clearance you'll have.

Treblig
 
I run P215/65R-15 which are 26" high on my 1968 GTS with no problems.
 
Ottmundr said:
68 fastback
small bolt pattern
going from 14x7 all around to 15x7 front this paycheck and 15x7 or 15x8 next paycheck.
old wheels are 3.25" backspace, new are 3.75" for the 15x7, and the 15x8 are 4.5" backspace.

I'm upgrading to 15" wheels, and I'm looking for information on front tire diameters. After all I've read about how BF Goodrich T/A radials are sticky as a lubed proctologist's finger, I decided not to bend over for that ride.

I almost pulled the trigger on some Mickey Thompson Sportsman S/T tires so I'd have matching front and back. Then I noticed the tire diameter of 215/70/15 came out to 26.85. Will that diameter fit without rubbing when turning or going over bumps etc?

Thanks for the help! :burnout:
Click to expand...
Did you end up getting these tires?
 
215-65-15 for sure ...215-70-15 would be better .. but i do not think that BF TA makes one ???
 
I run a m/t 27.5 x 4.5 x r15 on the front small bp not sure the offset. rubs #7 header tube(tube goes through the fender and under the frame) if you let it but they fit well and gives my 10quart pan the ground clearance it needs when the front comes back down. I was running a Volkswagen tire on the front with a stock pan before and they were cheep as heck and didn’t mind 130 mph and lasted longer than I used them.
 
Richard McLaughlin said:
Did you end up getting these tires?
Click to expand...

Yes sportsman ST all four corners. The rears are 255/60/15 27.1" diameter per MT's website. The fronts are 215/70/15.

They have worn really well over the last two years. Daily driver about 30 miles a day, and about 100 miles every weekend.

Front tires
IMG_20170806_200357.jpg


Rear tires
IMG_20170806_200410.jpg
 
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