The bolt circle diameter is correct. Another issue is the hub center. Most aftermarket wheels have larger hub centers so that they clear all vehicles hub sizes and hub rings are necessary to remove the vehicle weight from the wheel studs. They also help to center the wheel on the vehicle so that they run true. You can do a search on eBay under hub rings and will find that multitudes of rings are offered. Fiero hubs are 57.1mm. You can get hubs rings with 57.1mm internal diameter with an outer diameter that matches the hub size of the wheels. I bought VW wheels and needed these rings. Got the aluminum ones off eBay and they work great. Inexpensive too. Example listing below. http://www.ebay.com/itm/4pc...em58abe36499&vxp=mtr
But you will find that they tuck in under the fender a little more than the stock wheels and tires do for two reasons:
1. The stock 15 x 7 wheels have a 30 mm offset which means that your new 16 x 7 et 40 rims will be 10 mm further inboard;
2. The larger diameter wheel means your tire sidewall will be shorter and will bulge out less than the stock tires, making the wheel look even further tucked in.
I'm sure it will still look fine since these aren't huge numbers, and the stock wheels and tires do stick out a bit anyways.
Originally posted by gtoformula: ... hub rings are necessary to remove the vehicle weight from the wheel studs.
This is a common misperception... adapter rings are used only to center the wheel on the hub but they don't carry any loads. The vertical loads are carried by the friction created between the wheel and the hub flange by the clamping force of the wheel studs and lug nuts. Centering rings are important if you don't want vibrations, but they don't take any weight or loads.
I thought the OEM wheels on a Fiero all had an offset of 35mm.
EDIT: Perhaps it's just the 14" wheels which are 35mm? I'm confused now.
according to the "Fiero online service guide" at calgaryfieros.com the 13" alloys (and 13" and 14" steelies) are 42mm, the 14" alloys are 35mm and the 15" are 35mm for 84-87
for what it's worth, I run 17x7 ET38 on my car and as far as I can remember they were fine before doing the brake swap (which changed the ET to somewhere around 30-31mm)
Originally posted by PerKr: According to the "Fiero online service guide" at calgaryfieros.com ...the 15" are 35mm for 84-87
I have verified that the 15 x 7 lace wheels have a 30 mm offset... so have others:
quote
Originally posted by FTF Engineering: ALL years rear lace wheels are 15 x 7 x 30mm
Any source that tells you otherwise is wrong. Flat out wrong. The OSG is wrong... the offset for the rear lace wheels for all years is 30mm, not 35mm and not 41mm... and there is no difference between years on the rear. The rears are all the same for every year... 30mm.
I have confirmed the info above personally. Other sources with different numbers are simply incorrect information.
I have verified that the 15 x 7 lace wheels have a 30 mm offset... so have others:
quote
Originally posted by FTF Engineering:
ALL years rear lace wheels are 15 x 7 x 30mm
Any source that tells you otherwise is wrong. Flat out wrong. The OSG is wrong... the offset for the rear lace wheels for all years is 30mm, not 35mm and not 41mm... and there is no difference between years on the rear. The rears are all the same for every year... 30mm.
I have confirmed the info above personally. Other sources with different numbers are simply incorrect information.
But you will find that they tuck in under the fender a little more than the stock wheels and tires do for two reasons:
