So if I read this correct, the wheel could extend further inside the wheel well if it is shorter than where the portion of the strut/coil spring intrudes into the wheel well. So fitting a 9.5 inch wide wheel up front would require something short enough to fit slightly "under" the coil spring . Too tall a tire and you're going to interfere. correct?
The commonality of all the representations of rims shown above is that they are being shown with their respective hub surface on a common plane.
Norm
I think it's the wheelwell line that's throwing it off. According to the chart the '88 front 15x6x37mm is over an inch inside the wheel well edge. That would be great if it was, but to me the wheels on my '88 stick out like sore thumbs ( stock diamond spoke ). .
I think it's the wheelwell line that's throwing it off. According to the chart the '88 front 15x6x37mm is over an inch inside the wheel well edge. That would be great if it was, but to me the wheels on my '88 stick out like sore thumbs ( stock diamond spoke ). .
need to remember that the chart is showing the rim, not the tire. In your picture the tire clearly sticks out much further than the rim.Plus camber,toe,caster may all be different causing a different appearance.
[This message has been edited by Coinage (edited 07-31-2008).]
Also, are you sure that the front rims are actually '88s, the '88s have virtually no lip between the diamond pattern and the bead, . . . compared to the rear.
Also, are you sure that the front rims are actually '88s, the '88s have virtually no lip between the diamond pattern and the bead, . . . compared to the rear.
Right, I've got the zero dish type up front. There should be another line marker for the '88 front wheel well edge. This chart makes the '88 wheel look like it has more wheelwell gap than the pre-'88s.
So I was shopping wheels by size on www.discounttiredirect.com, and I started by asking it to find me some 17x9s on a 5 on 100 lug pattern. (stock Fiero) For the rear. To my amazement, not only did it find some, the price was $140 each, and there is a choice of offsets. from this thread's first diagram, I see the +38mm offset is the best choice, though I might need a 4mm spacer on each side. I can live with that. Then I set about finding matching front wheels, and the narrowest option is 8" wide, with a choice of +35mm or +47mm offsets. Since I'm planning on the LeBaron rotor upgrade, I'll need the +47mm offset. The fronts are $130 each. If you're curious, go look for style DR31 from a manufacturer named "Drag", who swears the wheels are perfect for street and drift use as well. Now, I need tires. I have a friend who can get me a killer price on Hankook tires, so I got on www.tirerack.com to see what I might like. For me, I settled on the Hankook Ventus V12 evo K110 tires, up front using a 225/45, which specs as 25.0" dia., and 7.7" tread width, for $90 each. On the rear, I wanted a 26" tire, such as a 255/45, but that's not listed, and the 255/40 specs as 25.0" dia, and 8.7" tread width. $ 107 ea. This is better for brake balance and center of gravity and acceleration anyway, if not looks or mileage. I'll post a pic when I get them mounted. Besides, this might save me from needing a rear coilover conversion.
[This message has been edited by Isolde (edited 02-14-2010).]
Is it safe to maching the inner part of a wheel - part that meets the hub in order to increase the offset. I've found a nice set of wheels that are 17 x 7.5 with a 32mm offset. They stick out by about 4mm which shouldn't be a problem on an 86 (please correct me if I'm wrong) but if I put them on an 88, the fronts will stick out by 22mm which is too much.
So again, it is possible to machine the inner hub of the wheel to increase the offset. I suspect wheels (non deep dish) with a low offset should have a thicker hub thus theoretically making machining to a larger offset possibe.
Has anyone heard of this type of machining being done?
[This message has been edited by Eau_Rouge (edited 03-18-2010).]
I just want to make sure I understand your chart correctly.
Basically, I can go with an 8-1/2" wide wheel in the front with an offset between 42mm and 52mm to keep the wheel itself within the wheel well. This does not account for tire width.
Same goes with the rear wheels, a 9-1/2" wheel should have an offset of 65mm if I read your chart correctly since a 41mm offset would be outside the wheel well.
Anyone else seeing the broken link things in the OP, instead of the diagram? I have the diagram saved on my other PC, all 4 sections of it. But I don't want to go to all that trouble if there's no need.
Are these for the outside wheelwell/fender edge only? If so then ok. But what is the inside (left) black line? Is that line only for 15" rims? Then that I would say is useless for most people using 17"+. If not then they are wrong. I was measuring two set of rims and those dimensions (left line) are not close. For example, that 7.5" with 38mm offset has less than 1" clearance and I have 1.5". The 9" with 35mm touches the line and I have 1/2" clearance.
Are these for the outside wheelwell/fender edge only? If so then ok. But what is the inside (left) black line? Is that line only for 15" rims? Then that I would say is useless for most people using 17"+. If not then they are wrong. I was measuring two set of rims and those dimensions (left line) are not close. For example, that 7.5" with 38mm offset has less than 1" clearance and I have 1.5". The 9" with 35mm touches the line and I have 1/2" clearance.
trying to go with 18 by 9.5 with 40mm offset rear on a 88 with 285/30/r18 ????
So i currently have 18 by 8.5 with 35 offset running 265 35 18 trying to go 9.5 anyone have a difinitive answere i tried to get mesurements from top of tire to strut but is difficult to say the least. I was thinking of getting one new rim 18/9.5 40 offset mount a 285/30/18 and see how it fits but if someone knows for sure if it will work please let me know!
I'm looking at some 18 x 9 w/ 42mm offset for the back could you add this to the list? I'm also running coilovers so I'm just looking at fender protrusion at this point.
Try this wheel and tire calculator. better than the miata.net on as it takes into account wheel and tire dimensions. you enter the stock specs on the left and then the new rim and tire specs on the right.
Sorry for the noob questions here, but I'm just making sure I understand the impact of the offset.
Ignoring all the numbers for a second - since the graph shows all the wheels on the same plane - am I correct in thinking that the closer the offset mark (for any wheel) is to the stock position, the better it is for bearing life and/or suspension geometry?
Like if I draw a line straight down from the offset mark on the 15x7 / 30mm Stock wheels, and I wanted to go with a 7.5" wide wheel, the closest matching offset mark for them is 35mm, so that would be the best selection of 7.5" wide wheels (out of those listed)?
I'm if mistaken, please let me know how I should be figuring out the optimum offset for any given wheel.
Secondly, I didn't see this in the thread (could have missed it), but what numbers do you compare/calculate to find out what the maximum sidewall height can be for a given width (let's say on a 17" wheel, since that's the size I'm looking for), and still clear everything safely when turning?
Originally posted by Trinten: Ignoring all the numbers for a second - since the graph shows all the wheels on the same plane - am I correct in thinking that the closer the offset mark (for any wheel) is to the stock position, the better it is for bearing life and/or suspension geometry?
You are correct. The dotted line is the wheel center offset from the hub. Extremes will put the bearing under excess stress. Remember, rotor thickness gets added to 88s fronts, and 84-up rears.
Yep, I'm alive. Sorry for the delay. 2 requests have been added.
[This message has been edited by Joe Torma (edited 07-12-2011).]
for your work!
