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Wheel adapter and offset question by jbs2212
Started on: 03-02-2014 11:45 AM
Replies: 14 (460 views)
Last post by: Tha Driver on 03-04-2014 03:57 AM
jbs2212
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Report this Post03-02-2014 11:45 AM Click Here to See the Profile for jbs2212Send a Private Message to jbs2212Edit/Delete MessageReply w/QuoteDirect Link to This Post
I've pretty much fell in love with the grey painted, factory Solstice wheels...It's been asked about, but to my knowledge no one is running them.

They're 18x8 with a 55mm offset, on 5x110. If I bought a quality set of 20mm adapters, that would make the offset 35mm, correct?

[This message has been edited by jbs2212 (edited 03-02-2014).]

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Bloozberry
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Report this Post03-02-2014 12:43 PM Click Here to See the Profile for BloozberrySend a Private Message to BloozberryEdit/Delete MessageReply w/QuoteDirect Link to This Post
Correct. But before you pull the trigger on these wheels, you should post what year car and what size wheels you currently have so that I or someone else can give you an idea how much further out (or in) the new wheels will sit compared to your old wheels. It would be a mistake to simply match the offsets between wheels of different widths and expect them to fit equally well. Remember that the extra 2" width still has to go somewhere.
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Report this Post03-02-2014 01:56 PM Click Here to See the Profile for FieroBoboClick Here to Email FieroBoboSend a Private Message to FieroBoboEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Bloozberry:
Correct. But before you pull the trigger on these wheels, you should post what year car and what size wheels you currently have so that I or someone else can give you an idea how much further out (or in) the new wheels will sit compared to your old wheels. It would be a mistake to simply match the offsets between wheels of different widths and expect them to fit equally well. Remember that the extra 2" width still has to go somewhere.

Bloozberry,
Wouldn't you also need to know what size tires the OP intended to use, and if they were for the front, and/or back wheels, or both?
And, wouldn't you also need to know whether or not the OP has coil-overs or stock struts and springs, since they will make a big difference in the clearances between the wheel/tire and the suspension?
I'm not saying you're wrong, I'm just trying to get thing clear in my own mind.

~ Bob ~

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"Its nice to be important.
Its more important to be nice."

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Bloozberry
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Report this Post03-02-2014 02:16 PM Click Here to See the Profile for BloozberrySend a Private Message to BloozberryEdit/Delete MessageReply w/QuoteDirect Link to This Post
Your understanding is correct... you'd need to know all of those things to get a final answer. I only asked him what year car and rims he had to avoid having to calculate everything for both pre-'88 cars and '88's.
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jbs2212
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Report this Post03-02-2014 04:38 PM Click Here to See the Profile for jbs2212Send a Private Message to jbs2212Edit/Delete MessageReply w/QuoteDirect Link to This Post
'86 GT. I'm thinking 225/40 tires.
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Report this Post03-02-2014 08:52 PM Click Here to See the Profile for BloozberrySend a Private Message to BloozberryEdit/Delete MessageReply w/QuoteDirect Link to This Post
I want to use the current wheels you have on the car as a reference point to demonstrate how much further inboard and outboard your new wheels will stick out, so I need to know what size rims you have on the car now. I know what the stock offsets are for the various stock wheels so if they're currently stock, then just state whether they're the 14 or 15 inch rims and I can do some calculations for you.
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jbs2212
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Report this Post03-02-2014 10:58 PM Click Here to See the Profile for jbs2212Send a Private Message to jbs2212Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Bloozberry:

I want to use the current wheels you have on the car as a reference point to demonstrate how much further inboard and outboard your new wheels will stick out, so I need to know what size rims you have on the car now. I know what the stock offsets are for the various stock wheels so if they're currently stock, then just state whether they're the 14 or 15 inch rims and I can do some calculations for you.


Awesome! Thank you very much! I have the stock 15" wheels on the car as of now. I'm also planning on lowering the front and rear an inch. Haven't decided how yet....
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Report this Post03-03-2014 02:39 PM Click Here to See the Profile for BloozberrySend a Private Message to BloozberryEdit/Delete MessageReply w/QuoteDirect Link to This Post
It looks like you should be OK in the rear with the combination you've suggested. This is a schematic of an '88 rear end that I've drawn the stock wheels and tires in blue and the Solstice wheels in red with the 225/40/18 tires you've suggested. The 20 mm spacer is in orange. Although the suspension isn't identical to your '86, the relative position of the wheel mounting flange to the fender is the same. I believe the strut on your '86 will be angled a little more vertically, but it looks like there is lots of room for that. The new rim and tire combo appears to bulge out a little more than the wheels and tires you currently have on the car, but it should look just fine. Bear in mind that although the cross section of the wheel has the proper diameter and offset, the rest is simply an estimate of the shape.



I can't help you on the front end since my drawings are for the '88 which are very different from the '86 front.

[This message has been edited by Bloozberry (edited 03-03-2014).]

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BrittB
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Report this Post03-03-2014 08:02 PM Click Here to See the Profile for BrittBSend a Private Message to BrittBEdit/Delete MessageReply w/QuoteDirect Link to This Post
Awesome drawing, you guys continue to blow me away! With 20mm spacers, are longer wheel studs required?

[This message has been edited by BrittB (edited 03-03-2014).]

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Report this Post03-03-2014 08:57 PM Click Here to See the Profile for BloozberrySend a Private Message to BloozberryEdit/Delete MessageReply w/QuoteDirect Link to This Post
The short answer is no. The long answer is that you need adapters not spacers. Your adapters will have a set of countersunk holes with the 5 x 100 pattern which you use to bolt the adapter to the original Fiero studs using the low profile nuts that come with them. They will also have a set of five new lugs already pressed into them with the 5 x 110 pattern which you bolt your wheels to using the nuts that normally hold the wheels on the Solstice. I've bought good quality adapters here in the past... these are the ones you're looking for... just select the thickness you want and fill in the other details: http://adaptitusa.com/5x100to5x110.aspx
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Report this Post03-03-2014 09:22 PM Click Here to See the Profile for LornesGTSend a Private Message to LornesGTEdit/Delete MessageReply w/QuoteDirect Link to This Post
The studs stick out so far on the original hub, so the adaptors have to be how thick minimum?

[This message has been edited by LornesGT (edited 03-03-2014).]

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Report this Post03-03-2014 09:43 PM Click Here to See the Profile for BloozberrySend a Private Message to BloozberryEdit/Delete MessageReply w/QuoteDirect Link to This Post
Well, a 20mm adapter is the thinnest one adaptitusa makes, so it can't be any thinner than that. As for how thick it must be so that the studs are flush with the outside face of the adapter, that's going to depend on how long your studs are, and whether or not your new wheels have recesses to accommodate studs that might stick up beyond the mounting surface of the adapter. Even if you have to shave off some of the stud's overall length to get it to sit flush, it will still be a safe length since the stud diameter is 12 mm's and the shortest you would have to make the studs is 20 mm's. That would result in thread engagement that's 1.6 times the diameter of the stud, which is fine.
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jbs2212
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Report this Post03-04-2014 12:22 AM Click Here to See the Profile for jbs2212Send a Private Message to jbs2212Edit/Delete MessageReply w/QuoteDirect Link to This Post
That is incredible!!!!! Thank you for taking the time. Judging from the offset diagram floating around on the forum, the front wheels should be about even with the fender lip pre-'88, but the tires will balloon out a bit.

Would it be a good idea to knock the old lug studs out and put in higher quality/strength studs in? I don't plan on thrashing the car...maybe a little "spirited" fun every once in a while. I haven't decided yet, but I might try to make or find some Pegasus center caps that look like the GT originals. The Solstice caps don't look bad either.

[This message has been edited by jbs2212 (edited 03-04-2014).]

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fieroall
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Report this Post03-04-2014 12:37 AM Click Here to See the Profile for fieroallSend a Private Message to fieroallEdit/Delete MessageReply w/QuoteDirect Link to This Post
Blooz I'm thinking of putting on some Caliber SRT4 rims on my 85GT. The specs are 19x7.5, 5x114.3, 38 offset, 67.1 hub. Can you tell me if they'll stick out too much or rub anywhere? The tires will be 225/45/19. Also what's the best thickness size to use? (20mm, 1", etc)

Thanks.
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Tha Driver
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Report this Post03-04-2014 03:57 AM Click Here to See the Profile for Tha DriverClick Here to visit Tha Driver's HomePageSend a Private Message to Tha DriverEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Bloozberry:

The short answer is no. The long answer is that you need adapters not spacers. Your adapters will have a set of countersunk holes with the 5 x 100 pattern which you use to bolt the adapter to the original Fiero studs using the low profile nuts that come with them. They will also have a set of five new lugs already pressed into them with the 5 x 110 pattern which you bolt your wheels to using the nuts that normally hold the wheels on the Solstice. I've bought good quality adapters here in the past... these are the ones you're looking for... just select the thickness you want and fill in the other details: http://adaptitusa.com/5x100to5x110.aspx


Those are not hub-centric adapters. The best place I've found for adapters is http://www.motorsport-tech.com/wheel_adapters.html .
They will make adapters that are hub-centric to fit your hub & whatever wheels you have.
~ Paul
aka "Tha Driver"

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