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  #1  
Old 8th September 2009, 12:05 PM
Rik178m Rik178m is offline
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Default Just won some alloys, will they fit?

Cant get my head around the offset issue today. Just won some alloys on ebay pcd 108 offset 15. I know the offset needs to be 35-40ish. So my question is how do I get these alloys to fit or won't they?
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Old 8th September 2009, 12:54 PM
slimtater slimtater is offline
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"May" be a problem:

http://www.driverstechnologyassociat...eel-offset.htm
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Old 8th September 2009, 01:14 PM
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AshG AshG is offline
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they will stick out about 20mm further than a wheel that is the correct ofset. if you have wide arches on the rear it shouldnt be a problem
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Old 8th September 2009, 07:49 PM
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RAYLEE29 RAYLEE29 is offline
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Bumpsteer!!
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Old 8th September 2009, 10:01 PM
Matthew Matthew is offline
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Quote:
Originally Posted by RAYLEE29 View Post
Bumpsteer!!
I don't think that's right. Bumpsteer is caused when the steering rack isn't correctly aligned (or the right length), and doesn't have anything to do with the wheel offset. IF you ever measure it then you don't usually have the wheels attached anyway.

I think it does have some other effects though - something to do with how well the steering self centres I think.

Matt
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  #6  
Old 8th September 2009, 11:13 PM
Rik178m Rik178m is offline
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What exactly is bumpsteer?

If they dont work I'll just put them back on ebay.
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  #7  
Old 8th September 2009, 11:35 PM
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alga alga is offline
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Bumpsteer is the change of the effective length of tie rods due to the suspension travel. Nothing to do with wheel offset.
A wheel offset too low will shift the contact patch out of correct alignment with regard to the kingpin axis, thus increasing the scrub radius. The effect will be unsettled steering, exaggerated reaction to unevenness of the road, especially when braking.
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Old 9th September 2009, 07:48 AM
Matthew Matthew is offline
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If you want a more detailed explanation then this site http://www.longacreracing.com/articles/art.asp?ARTID=13 has a good explanation together with instructions on how to measure and correct it.

Matt
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Old 9th September 2009, 01:06 PM
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RAYLEE29 RAYLEE29 is offline
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Default Bumpsteer

Hi,
I believe there is more than one way of causing bumpsteer but i may be wrong, ive been modding cars for nearly 30 years and have experience of people fitting wheels with too much offset.
if you move the contact patch too far away from the middle of the point where the kingpin inclination hits the floor you will adversly effect the handling
when you go over a bump the car will try to steer into the bump if thats not bumpsteer what is it??
anyone remember the carlos fandango ad with the anglia with oversize wheels!!
Ray
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Old 9th September 2009, 01:19 PM
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Bonzo Bonzo is offline
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Quote:
Originally Posted by RAYLEE29 View Post
anyone remember the carlos fandango ad with the anglia with oversize wheels!!
Ray
That's a classic Ray.

Still makes me smile

Carlos Fandango
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I am not a complete idiot...........Some of the parts are missing !!
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