4x108 adapter - centerbore question

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fatmatt
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4x108 adapter - centerbore question

Post by fatmatt »

I recently purchased a set of American Racing Lemans wheels. They are 15x5.5 in a 4x108 bolt pattern. I'm shopping for adapters now and am a little puzzled as to what I need. it looks to me as if I need a centerbore of about 72mm to clear the hubs. Is this correct? Should I worry about being hubcentric? I think these will be fine but I'm not sure.
http://www.ebay.com/itm/262571459996
I'm wondering if I'd be better off taking the wheels into a tire shop and asking them. Car is otherwise stock except for comp springs.
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Alvin
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Re: 4x108 adapter - centerbore question

Post by Alvin »

I would find the correct wheel (4x114.3 pcd), sell these to an Alfa guy that can use them.

If you are set on using them on your roadster take into consideration that you will be adding 1" to the offset with your adapter. 73mm is considered "enough" for center bore clearance for the front hubs.
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fj20spl311
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Re: 4x108 adapter - centerbore question

Post by fj20spl311 »

Have those wheels redrilled to 114.3 if you must....selling them and buying the correct wheels or VTO copies is a better idea.

BTW, if you have them redrilled, they will only be slotted about 1/8". so with the washer, no one cant tell.
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fatmatt
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Re: 4x108 adapter - centerbore question

Post by fatmatt »

fj20spl311 wrote:Have those wheels redrilled to 114.3 if you must....selling them and buying the correct wheels or VTO copies is a better idea.

BTW, if you have them redrilled, they will only be slotted about 1/8". so with the washer, no one cant tell.
You could just redrill on top of the existing holes without welding them shut first?
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pebbles
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Re: 4x108 adapter - centerbore question

Post by pebbles »

The old unilug wheels from the 70s used an eccentric washer to fill the oval washer counter bore. Re drilling the wheels and counter boring the washer step, may cost more than the wheels did.
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Pjackb
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Re: 4x108 adapter - centerbore question

Post by Pjackb »

Hey Fatmatt,
The first question you need to answer in order to properly guide you is what is the offset of the wheels?
If they are low offset already let's say +15 introducing a 25mm adapter/spacer would mean your new offset would now be-10 which may be too agressive.
If you don't have the offset you can use this link to see how to measure http://forum.jdmstyletuning.com/showthr ... -your-Rims

The second thing you need to know is if the wheels have recessed cavities in the back

Once you have all this you can get the proper spacer/adapters ,there a company I've dealt with in the past that will make you anything you need at a fairly reasonable minimum width is 15mm and while you don't need it I highly recommend hubcentric
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Pjackb
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Re: 4x108 adapter - centerbore question

Post by Pjackb »

Pjackb wrote:Hey Fatmatt,
The first question you need to answer in order to properly guide you is what is the offset of the wheels?
If they are low offset already let's say +15 introducing a 25mm adapter/spacer would mean your new offset would now be-10 which may be too agressive.
If you don't have the offset you can use this link to see how to measure http://forum.jdmstyletuning.com/showthr ... -your-Rims

The second thing you need to know is if the wheels have recessed cavities in the back to fit the OEM lugs

Once you have all this you can get the proper spacer/adapters ,there a company I've dealt with in the past that will make you anything you need at a fairly reasonable minimum width is 15mm and while you don't need it I highly recommend hubcentric
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fj20spl311
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Re: 4x108 adapter - centerbore question

Post by fj20spl311 »

fatmatt wrote: You could just redrill on top of the existing holes without welding them shut first?
YES...better if the wheels are "hub centric", but if the holes are CNC machined, the shanks will keep the wheel centered.
You could also machine for the "large" diameter wheel lug shanks.
Some care will need to be used in tightening your wheels, but that's always a good idea.

I still suggest you sell those wheels and buy new wheels.
Phil
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fatmatt
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Re: 4x108 adapter - centerbore question

Post by fatmatt »

Pjackb wrote:Hey Fatmatt,
The first question you need to answer in order to properly guide you is what is the offset of the wheels?
If they are low offset already let's say +15 introducing a 25mm adapter/spacer would mean your new offset would now be-10 which may be too agressive.
If you don't have the offset you can use this link to see how to measure http://forum.jdmstyletuning.com/showthr ... -your-Rims

The second thing you need to know is if the wheels have recessed cavities in the back

Once you have all this you can get the proper spacer/adapters ,there a company I've dealt with in the past that will make you anything you need at a fairly reasonable minimum width is 15mm and while you don't need it I highly recommend hubcentric
The wheels do have recessed cavities. It looks like I've got a +20mm offset so a 1" adapter would put me at right around zero? I measured it all out last week and it looks like with the adapter I'll be moving the wheels out about 15mm over stock. It looks to me like it will fit, especially if I go with some smaller rubber than the 175R14 that are on the car now. Are the stock wheels hubcentric? It looks to me like they don't quite meet the hub.
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Pjackb
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Re: 4x108 adapter - centerbore question

Post by Pjackb »

In general on budget 1" adapter like the one posted thickness should be 25,4mm (but usually vary between 24mm to 27mm) which would bring you to a negative offset of -5
This is equivalent to 7" wheel with +14 or 6.5" wheel with a +8 , I'm not yet familiar enough with the cars to tell you if it will fit but I seem to have read that it works
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