Peter:
OK, backspace it is.
At 06:27 AM 07/17/2000 -0400, LBCarNut wrote:
>Bob,
> You do mean Backspace not offset don't you. Offset is the distance
>that the hub is from the center of the wheel width. If the hub is offset
>towards the outside it is positive offset ala front wheel drive, if
>towards the inside it is negative. Backspace is the distance between the
>hub and the rim.
>
>Peter.
>Charlotte NC
>
>Bob Spruck wrote:
>>
>> Interested Listers:
>>
>> I have been searching for a set of wheels for my ' 67 Midget vintage race
>> car for a while now. I use 5.5" wide Western alloys with Hoosier A70s when
>> I race with HSR. I have begun to race with VDCA, a new group that is
>> much more concerned with period authenticity and to comply with their
>rules, I
>> can only use street radials on a 5.0 " wide wheel. Most of my fellow
>> vintage racers use the Panasport Minilite replicas but I want something
>> different and cheaper. In my search, I've looked at wheels from all the
>> stock Spridgets, Chevy Vega, and BMW 2002 and thought some of you might be
>> interested in my findings.
>>
>> Assuming we are only talking about 13", four stud, 4.0" bolt circle wheels,
>> all the non Spridget wheels seem to have problems. Not insurmountable, but
>> challenging, nonetheless. The two problems are center hole size and rear
>> offset. The Spridget has a rather large "cone" on the front hub and rear
axle
>> "mushroom" on the flange that have to fit inside the center hole of the
>> wheel in order for the
>> wheel to sit flush against the front hub flange and the rear drum. If the
>> center hole on the wheel is not large enough, the wheel is not brought up
>> tight to the mating surface by the wheel nuts, it wobbles and you have
>> serious problems. A 1/4" thick wheel spacer will solve this problem, but
>> the spacer
>> may throw the wheel/tire too far out so that it
>> interferes with the fender on a square wheel arch car. It may also cause
>> the studs to be too short for sufficient thread engagement with the lug nut.
>> This interference shouldn't be a problem on round wheel arch cars.
>>
>> Another detail to consider is the configuration of the lug nuts and the
>> wheels. Spridget wheels and nuts have a different bevel than American
>> wheels. Some alloys use shoulder nuts and washers so there isn't a problem.
>> I installed 7/16 " studs from Pep Boys on the race car and had to use
>> American nuts to fit them. When I temporarily used Rostyle wheels, the
>> bevel of the American nut did not match the bevel on the British wheel. I
>> had to take 16 stock chrome lugnuts, drill the right size hole all the away
>> through, and tap them for the 7/16 x 20 studs. Also make sure the studs are
>> long enough to fully engage the nuts. With the spacers, I have to convert
>> again from the 1 1/2 " long studs to the 2 1/8" studs and use open nuts.
>>
>> The other problem in non-Spridget wheels is the rear offset. As you can
>> tell by looking at the following dimensions for the non-Spridget wheels,
>> the offsets can be quite different than stock. If the offset varies from
>> stock too much, you
>> once again have clearance problems with the sheet metal. The smaller the
>> rear offset dimension, the further the wheel protrudes towards the outside
>> of the
>> car and the inside of the fender. I have found that any wheel with a rear
>> offset between the stock 3.0"
>> and about 4 3/8 " fits fine on a SWA car.
>>
>> I have determined that Vega wheels won't work on my SWA car, so they are
>> available if anybody wants them for a RWA car.The BMW 2002 steel wheels
>> look like they will work fine. They are 100 mm bolt circle but otherwise
>> seem to
>> fit. Of course, I will have them tested for cracks and trueness before I
>> sandblast and paint them. I hope the information below helps and you don't
>> have to accumulate all the wheels I have before you finally find something
>> that fits.
>>
>> STYLE WIDTH REAR OFFSET
>>
>> BUGEYE ? ?
>> SPRIDGET, STEEL, SOLID 3 ½ 3
>> SPRIDGET, WIRE 4 3
>> ROSTYLE, EARLY, 8 SLOTS 4 ½ 3 3/8
>> ROSTYLE, LATE, 4 SPOKES 4 ½ 3 3/8
>> VEGA, STEEL 5 2 5/8
>> VEGA,GT, STEEL 6 ?
>> BMW 2002, STEEL 5 3 11/16
>> WESTERN, ALLOY 5 ½ 4 3/8
>>
>> Regards,
>>
>> Bob Spruck
>> Sharpsburg, GA
>> ' 67 Midget Vintage Racer
>> ' '72 Midget Weekend Car
>> 4 parts cars in the woods
Bob Spruck
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