question about rally wheels
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Joined: Nov 2000
Posts: 79
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From: yerington nv 89447 USA
question about rally wheels
Does anyone know what the back spacing on original rally wheels is?
I need new wheels the ones on my vette are to badly rust pitted to refinish,
there's several combo sets on ebay ie wheels trim rings and center caps in
the 300.00 range but they have different back spacing??
Can anyone help me?
thanks
dave
I need new wheels the ones on my vette are to badly rust pitted to refinish,
there's several combo sets on ebay ie wheels trim rings and center caps in
the 300.00 range but they have different back spacing??
Can anyone help me?
thanks
dave
Melting Slicks
Joined: Aug 2000
Posts: 2,310
Likes: 1
Re: question about rally wheels (daves 72)
I think the range you quoted is correct. I know I've read it somewhere but, of course, I can't find where in the pile of STUFF I have here :crazy:
I believe that you measure backspacing by laying a straight edge across the back (inside edge) of the wheel and measuring the distance from a lug hole to the striaght edge. Hopefully, someone will either confirm or refute.
I believe that you measure backspacing by laying a straight edge across the back (inside edge) of the wheel and measuring the distance from a lug hole to the striaght edge. Hopefully, someone will either confirm or refute.
Thread Starter
Advanced
Joined: Nov 2000
Posts: 79
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From: yerington nv 89447 USA
Re: question about rally wheels (jerryp58)
jerryp58
Thanks now i can go measure mine and see what they are.
Did the C3s over the years have different back spacing?
Thanks
dave
Thanks now i can go measure mine and see what they are.
Did the C3s over the years have different back spacing?
Thanks
dave
Instructor
Joined: Jul 2001
Posts: 168
Likes: 4
From: central Washington state
Re: question about rally wheels (daves 72)
Dave;
OEM backspacing on the Corvette rally wheel is 4 inches. To measure backspacing, lay the wheel face down, put a straight edge across the diameter of the wheel (not to be confused with the tire) and measure from the bottom edge of the straight edge to the wheel's axle flange mounting surface. To do this with the tire mounted on the wheel requires a straight edge that is exactly the correct length, i.e. for a 15" wheel, 16 1/4". If this sounds confusing, it will all become clear when you take the measurement.
OEM backspacing on the Corvette rally wheel is 4 inches. To measure backspacing, lay the wheel face down, put a straight edge across the diameter of the wheel (not to be confused with the tire) and measure from the bottom edge of the straight edge to the wheel's axle flange mounting surface. To do this with the tire mounted on the wheel requires a straight edge that is exactly the correct length, i.e. for a 15" wheel, 16 1/4". If this sounds confusing, it will all become clear when you take the measurement.
Thread Starter
Advanced
Joined: Nov 2000
Posts: 79
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From: yerington nv 89447 USA
Re: question about rally wheels (noxqsz)
noxqsz
Thank you, now i get it.(how to measure i mean)
What will happen if i put on a wheel with 4.25 or 4.5 back spacing,will the tires rub on the body,calipers or suspenion? the prices on these combos a pretty good most of the time.thanks everyone
dave
Thank you, now i get it.(how to measure i mean)
What will happen if i put on a wheel with 4.25 or 4.5 back spacing,will the tires rub on the body,calipers or suspenion? the prices on these combos a pretty good most of the time.thanks everyone
dave
Instructor
Joined: Jul 2001
Posts: 168
Likes: 4
From: central Washington state
Re: question about rally wheels (daves 72)
Dave;
Diffcult to say exactly what effect more backspacing might have. I can tell you that I put a set of chrome ralleys on my '73 with about 4 1/2" backspacing, and the wheel made slight contact with the outside bleeder on the passenger rear brake caliper. I remedied the problem by grinding on the wheel a bit, only a tiny fraction of an inch did the trick. I can also see that the tire has made very slight contact with the frame on the driver side front, apparently when I turn the wheels all the way to the left. It's not serious enough to keep me from driving the car, but I'll be changing to wheels with 4" backspacing next spring, just the same. I suppose the best thing to do in your case is to trial fit whatever wheel/tire combination you have in mind. Any tire shop worth doing business with will gladly do that for you.
Diffcult to say exactly what effect more backspacing might have. I can tell you that I put a set of chrome ralleys on my '73 with about 4 1/2" backspacing, and the wheel made slight contact with the outside bleeder on the passenger rear brake caliper. I remedied the problem by grinding on the wheel a bit, only a tiny fraction of an inch did the trick. I can also see that the tire has made very slight contact with the frame on the driver side front, apparently when I turn the wheels all the way to the left. It's not serious enough to keep me from driving the car, but I'll be changing to wheels with 4" backspacing next spring, just the same. I suppose the best thing to do in your case is to trial fit whatever wheel/tire combination you have in mind. Any tire shop worth doing business with will gladly do that for you.
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Racer
Joined: Nov 2000
Posts: 369
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From: Finland
Re: question about rally wheels (daves 72)
Dave
I think the wheels you've seen on ebay are generic replacements, hence the slightly different backspacing. I'm pretty sure all original 15*8 wheels had the same back spacing, the corvette parts catalogs only list one wheel for all years 69 to 82. BTW I just noticed that my 245/60 tires slightly rub the frame in front. I've allways thought that I have 4" BS rallys but not absolutely sure anymore :confused: I know the previous owner fitted new rallys just before selling the car to me. However the tires are very close to the fender lip too so it might be quite allright. I'm just wondering how people manage to fit 265 or 275 tires under their cars without problems?
rgds Tomi
I think the wheels you've seen on ebay are generic replacements, hence the slightly different backspacing. I'm pretty sure all original 15*8 wheels had the same back spacing, the corvette parts catalogs only list one wheel for all years 69 to 82. BTW I just noticed that my 245/60 tires slightly rub the frame in front. I've allways thought that I have 4" BS rallys but not absolutely sure anymore :confused: I know the previous owner fitted new rallys just before selling the car to me. However the tires are very close to the fender lip too so it might be quite allright. I'm just wondering how people manage to fit 265 or 275 tires under their cars without problems?
rgds Tomi
