So, I have been on the prowl for replacement rims. I would like to go Minimum 17, hopefully 18 or even 19.

I am assuming the following "facts" :

Stock front is 15x6x37et with 205/60/15
Stock rear is 15x7x30et with 215/60/15

At first I was looking for the perfect mathematical match (plus of minus a few mm's) for the increase in rim width for offset. For example. Bumping up the rears from 7 to 7.5 or 8, and also adding half of that width to the offset to keep the wheels located at the stock exterior position (if that makes any sense). Likewise for the front.

After much frustration I started to look at the possibility of NOT running staggared widths/offsets. So I found a set of rims I really like, 18x7.5x35 . My thoughts were to run these on all 4's with a 215 in the front and a 235 (or 245 if possible?) on the rear).

Enter this handy tool :

http://www.rimsntires.com/specs.jsp

I entered in the stock specs for the front on the left and my new rims on the right

So

205/60/15 on 15x6x37et

versus

205/60/18 on 18x7.5x35et

(I went with the same tire width/sidewall to remove that from the equation).

It spat back the following :

Clearance: Package 1 Package 2
Suspension Assuming that this is OEM wheel/tire and there is no any problems with clearance on both sides >>> 100% clear (leaves even more room than OEM)

Fenders Package will stick out 2 mm (0.1'') farther. Acceptable for most cars.

Wheelwells Will fill out the wheelwell by extra 38 mm. Make sure that you have enough room under the fender. If not, consider lower profiles or smaller rims


I was under the impression that if I were to increase the front rim with by 1.5 inches (as I am), the offset would have to increase by .75 of an inch in order to keep the lip in the same location.

Am I confused?

You're not confused... the program clearly is. Converting to metric, your new 7.5" wheels would need a total of 37 mm (stock) plus an additional 19 mm (0.75") of offset to have the outside rim edge in the same location, leaving you with a wheel that's 7.5 X 56 mm. Because the new rims actually have only a 35 mm offset, that means they will stick out 56 mm - 35 mm = 21 mm (0.827" or 13/16") more than stock on each side.

Edit to add: This applies to the front only.

[This message has been edited by Bloozberry (edited 04-23-2012).]

quote Originally posted by Bloozberry: You're not confused... the program clearly is. Converting to metric, your new 7.5" wheels would need a total of 37 mm (stock) plus an additional 19 mm (0.75") of offset to have the outside rim edge in the same location, leaving you with a wheel that's 7.5 X 56 mm. Because the new rims actually have only a 35 mm offset, that means they will stick out 56 mm - 35 mm = 21 mm (0.827" or 13/16") more than stock on each side.

Thanks, thats what I feared. It just does not seem possible to run the same size rim on all four corners and make it look normal An inch is too much for me. Its seriously limiting my options. Bwahh.

I ran a set of ALT AT-148's in a 17X7.5 width 35 offset wheel all around on my 88 GT. I used 215/45/17's in front and 245/45/17 in back on these wheels. The car looked very nice when viewed down the side and had no interference problems. Then I changed to Falken Torque 5's in 18X7 f40 offset fronts with 225/40/18's and 18X8 35 offset with 265/35/18 rears. the also look very good with no interference problems on an 88. Hope this helps.

You can run 7.5" 35mm on the front but is definitley not the best for an 88. They will stick out a bit. Better to find a 7" wheel for that offset. Yes finding wheels for an 88 is a problem. Not too many options for staggered. Main problem is the front. You can get 7, 8, 9 or 9.5" width for rear with 35mm and will fit fine but then that same style will not have a matching 7" wheel for the front. I personally think a 7" with 45-38m offset fits the best the front. Good luck on your search.

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Red: TPI V8 + 6-Speed White: 3800SC auto
304rwHP/366rwTQ

I went with ASA AR-1's, because of the option to get different widths and offsets in the same style. Turned out nice.

Edit: Rims on page 1 of my build thread (link in sig).


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Currently in the middle of my 88 + 3800NA swap

[This message has been edited by aaronkoch (edited 04-23-2012).]

Thanks guys. While on the subject. I am still running the stock springs in the back. I know a lot of people run an 8 inch in the back, and they normally have coilovers. Curious if anyone has had luck with an 8 with stock rear struts/springs.

Just trying to get the widest array of options.

I ended up going with a 17x7 et40 front and 18X8 et35 rear for my 88GT. Fitment is spot on. My old 88GT I went with RPF1's (my fav rim) in 17x8 et45 and 18x9 et35 and the fronts stuck out about 5mm too much. Wider fenders would solve that problem... but if Enkei would make a 40mm offset would solve everything.

https://www.fiero.nl/forum/F...113960.html#lastpost
You can read through what I ended up with.

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Anthony

'88 Fiero GT 5-spd "barn find"

www.DriveFasterNow.com

I'm using stock sized springs (lowering springs, but normal style) and my 8" rim fits like a glove. 88's lean in more than previous years, makes our lives a bit easier in that regard.

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Currently in the middle of my 88 + 3800NA swap

Anyone running Spacers on the rear? I am thinking of getting something reasonably close and then running a 10-15 mm spacer on the back.

I really love these :

http://www.1010tires.com/wh...low+%2D+Hyper+Silver

the problem is I was going to run 18 (or 17 x 8) on the front, but it only goes upto 45.

Additionally I guess the wide dish setup will make them stick out even further (Correct?)

I used Enkie Falcon 17x8 (38), 17x7 (45). With Kumho Esctsa XS 215 and 245/45's. Perfect offset.

https://www.fiero.nl/forum/Forum1/HTML/083204.html

Pictures on my build thread

Rob

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88 Coupe, CJB T-TOP, LS376 and a GT clip
Build Thread: https://www.fiero.nl/forum/Forum1/HTML/083204.html
Youtube: http://www.youtube.com/watch?v=QAH9yjw6XR0
Web Site: http://www.vafieros.com/
Facebook: http://www.facebook.com/pag...ciation/471024735229

So it looks like my 17x8 @ 45et might actually not be bad at all. I would only see less then a cm more on the outside then yours. Thanks a ton.

I am still curious about how a deep dish effects that overall distance.

Given two rims with the same width and offset, if one has a 2 inch lip, and I expect the edge of the wheel to sit an additional 2 inchs further compaired to the other wheel , or do the spokes on the deep dish rims typical taper in, so the edge of the lip sits roughly the same as a non deep dish one?

Make sense?

quote Originally posted by GodSend: Given two rims with the same width and offset, if one has a 2 inch lip, and I expect the edge of the wheel to sit an additional 2 inchs further compaired to the other wheel , or do the spokes on the deep dish rims typical taper in, so the edge of the lip sits roughly the same as a non deep dish one? Make sense?

Two wheels with the same width and offset will have the front edge of the wheel in exactly the same place.
If there is a 2" lip on one of them, it's because the spokes are curved to provide that lip.

When you hear the term "offset", this is what it means...

If you draw an imaginary line through the wheel, that separates it into a front half and a back half, that will be the center line.
The offset is how far in one direction the bolt/hub flange is moved from that center line.
A more positive offset will move the hub flange out towards the face of the wheel (which has the effect of tucking the wheel farther under the car.)
A more negative offset will move the hub flange in, towards the back edge of the wheel (which has the effect of poking the wheel farther out from under the car.)
A 35mm offset places the hub flange 35mm (about 1.5 inches) outside of the centerline of the wheel.
A 45mm offset places the hub flange 45mm (almost 2 inches) outside of the centerline of the wheel, tucking the wheel farther under the car.

It's confusing, and sounds bass-ackwards, but it's true.

Offset is often confused with back-spacing, which is nothing more than the measurement from the back of the hub flange, to the back edge of the wheel.
Back spacing doesn't take into account how wide the wheel is, or how much sticks out from under the car.

HTH.

[This message has been edited by Raydar (edited 04-29-2012).]

Well I like the sound of that. I guess my only other question would be if there woudl be rubbing up front on a 88 with 17x8 45et (or 18x8 et)... not sure what size of tire...35-45 sidewall.. 215-225 ..