Wheel Size....
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Wheel Size....
Hey I know there is already a topic sort of like this but mine is a bit different. Ok the question is, what is the biggest tire size that can fit on the back of a '72 road runner if it is mounted on a Rallye size 15-8 with NO backspace?
Could a 275/60-15 work, or maybe a 295/60-15?
Could a 275/60-15 work, or maybe a 295/60-15?
- Dave
- Site Admin
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- Joined: Mon Oct 06, 2003 1:37 pm
- My Cars: 71 Plymouth Road Runner (Project Blue Bird)
71 Satellite Sebring Plus (383/2bbl/auto) - Location: Cleveland, OH
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I'm not sure where you are going with "NO backspace". That would have the wheel itself partially outside the quarter panel. I'm not sure you could get a set of rallye wheels made up with no backspace at all and have them look ok from the front.
Unless you mean a 15x8 rallye with just the factory backspace, which I think is 4.5". (Ok all you rallye wheel guys, correct me if I'm wrong there. ) Anyway, if you mean just using a stock rim, you could easily to 275's, 295's would be pretty close clearance to the quarter panel. On the rims I have for Project Blue Bird, they have 4.75" backspace, and I have the 295's exactly centered in the wheel house, with 3/4" clearance from both the spring on the inside and the quarter panel on the outside. Figure the factory rallye would move that whole thing 1/4" outward, so you'd be looking at 1/2" or less from the quarter.
If you looked at 275's you'd have a good bit more clearance due to the smaller tire in general, but also, you'll drop a good bit in section width on the tire since you wouldn't have the same sidewall bulge that you do fitting a 295 on an 8" rim.
Hope that helps!
Unless you mean a 15x8 rallye with just the factory backspace, which I think is 4.5". (Ok all you rallye wheel guys, correct me if I'm wrong there. ) Anyway, if you mean just using a stock rim, you could easily to 275's, 295's would be pretty close clearance to the quarter panel. On the rims I have for Project Blue Bird, they have 4.75" backspace, and I have the 295's exactly centered in the wheel house, with 3/4" clearance from both the spring on the inside and the quarter panel on the outside. Figure the factory rallye would move that whole thing 1/4" outward, so you'd be looking at 1/2" or less from the quarter.
If you looked at 275's you'd have a good bit more clearance due to the smaller tire in general, but also, you'll drop a good bit in section width on the tire since you wouldn't have the same sidewall bulge that you do fitting a 295 on an 8" rim.
Hope that helps!
Dave
Founder - The Road Runner Nest
71 Plymouth Road Runner (Project Blue Bird)
71 Satellite Sebring Plus (383/2bbl/auto)
Founder - The Road Runner Nest
71 Plymouth Road Runner (Project Blue Bird)
71 Satellite Sebring Plus (383/2bbl/auto)
- Dave
- Site Admin
- Posts: 844
- Joined: Mon Oct 06, 2003 1:37 pm
- My Cars: 71 Plymouth Road Runner (Project Blue Bird)
71 Satellite Sebring Plus (383/2bbl/auto) - Location: Cleveland, OH
- Contact:
72, don't feel bad, we all have those days. Only way to learn is to ask questions. As I've always said, there's no such thing as a dumb question - just dumb people... er... no wait... that's dumb ANSWERS.. yea, thats it.
Anyway, glad I was able to help you. If you want, I can see if I can dig up the spreadsheet I used in working out tire widths, wheel size and backspace. I'm not sure if I saved it, but knowing me, it's around here somewhere.
71GTX, well, here's what I have:
A couple from when I did a test fit on my SSP:
This is the only one I have of them on the Road Runner. It doesn't have the best detail, but it's better than nothing.
Anyway, glad I was able to help you. If you want, I can see if I can dig up the spreadsheet I used in working out tire widths, wheel size and backspace. I'm not sure if I saved it, but knowing me, it's around here somewhere.
71GTX, well, here's what I have:
A couple from when I did a test fit on my SSP:
This is the only one I have of them on the Road Runner. It doesn't have the best detail, but it's better than nothing.
Dave
Founder - The Road Runner Nest
71 Plymouth Road Runner (Project Blue Bird)
71 Satellite Sebring Plus (383/2bbl/auto)
Founder - The Road Runner Nest
71 Plymouth Road Runner (Project Blue Bird)
71 Satellite Sebring Plus (383/2bbl/auto)
- road chicken
- GTX (RS)
- Posts: 668
- Joined: Thu Oct 09, 2003 11:21 pm
- Location: SE WI
To convert Metric to inches just multiply by .03937
for tread width....
EX. 275/60/15 275mm = 275 X.03937 = 10.82 inches tread
Tire diameter
10.82" X .6 ,(60%)= 6.5" sidewall height
6.5 X 2, ( to sidewalls) = 13" + 15" diameter wheel = 28" tire diameter
That will get you your tire dimension- the backspacing you'll have to figure with a straight edge from the wheel mounting face and a ruler to the wheel housing lip and spring. You should be able to determing the back spacing from there.
for tread width....
EX. 275/60/15 275mm = 275 X.03937 = 10.82 inches tread
Tire diameter
10.82" X .6 ,(60%)= 6.5" sidewall height
6.5 X 2, ( to sidewalls) = 13" + 15" diameter wheel = 28" tire diameter
That will get you your tire dimension- the backspacing you'll have to figure with a straight edge from the wheel mounting face and a ruler to the wheel housing lip and spring. You should be able to determing the back spacing from there.
4th generation B bodys- there is no substitute.
68 383, Street Demon 750, RPM top end,484/284/108 poo poo cam "-5 spd 4:10 SG, 4whl disk, Helwig Anti-Sway, Poly bushings,Firm Feel Box, HD Linkage, 1" t-bars, 7 leafs Springs
68 383, Street Demon 750, RPM top end,484/284/108 poo poo cam "-5 spd 4:10 SG, 4whl disk, Helwig Anti-Sway, Poly bushings,Firm Feel Box, HD Linkage, 1" t-bars, 7 leafs Springs