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Discussion Starter #1
Does anyone no what wheel offest is needed on the gt. Nearly picked some up few days ago only to be told that the gt needed an offset of 98 and the wheels were 38. One website said a gt can take offset 35 to 40. If anyone knows exactly jus to put this wheel issue to bed. Cheers
 

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98 is the PCD, 5x98 to be exact... that website is about right... my stock 17s are 40. most aftermarket IIRC will be 35..
 

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Discussion Starter #3
So is the offset of 35 ok to fit? If its wrong what kind of diffrence does it make to the car?
 

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will move the wheel out 5mm, if the rim is wider, say 7.5 inch instead of 7 inch then thats 13mm wider rim, so 6.5mm more each side, with a 35 offset you gain 5mm so the wheel would only protrude inwards by about 1.5mm
 

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ET35 for the GT.
They have the same wide arches as the GTA.
 

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AO Silver Member, 155 Lounge Winner 09
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The offset is one parameter of wheel design, but in itself has little meaning without knowing the width of the wheel (and tyre).

If the wheel is only 7" wide, an offset of +20mm is probably do-able. But if the wheel is 8.5" wide, ET25 would be too little and the wheels would sit too outboard and the tyres will rub, so it would need to be more like +35mm.

Hence, there's a relationship between the offset and width, as to what will fit the car and look good. A google search will link you to many websites explaining wheel specs; very useful to have at least a basic understanding.

If you have a wheel in mind, ask about it, because people will know if it fits and looks good. Or are you looking at aftermarket wheels?

Stuff like the 17" Supersports look decent, but the offset is relatively high, so they sit 'very inboard' and looks 'bad' IMO. So it's an example of a wheel that fits, but doesn't really suit the car.

As above, you are unlikely to notice a difference in handling unless you drive the car hard and fast. But increased 'track' will confer increased stability, but can adversely affect turn-in/cornering bite.

:)
 

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what pcd are they, i've got some momo's on the way from italy but they only came in 5/100 so i've got to run wobble bolts
 

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AO Silver Member, 155 Lounge Winner 09
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There's other names for these bolts, including 'variation bolts'. They look like this (used on my 155):
http://pic20.picturetrail.com/VOL97/467659/20306697/330699906.jpg

Because the wheels you're looking at have a bolt pattern that's 5x100, the radius of the PCD is 1mm bigger than the Alfa 5x98 pattern. Wobble bolts have a loose washer/collar, allowing you to fit 5x100 wheels onto the 5x98 Alfa hubs.

What is more important (for wheel safety/fitment), is that the centre bore is made perfectly correct. The centre bore is the sizable hole right in the middle of the wheel. For the GT (and other contemporary Alfas), the bore diameter is 58.1mm wide. This hole fits snuggly over the hub...which is 58.1mm diameter. The weight of the car is transferred through the centre bore, so this is critical. The wheel nuts merely hold the wheel in position on the hub, and do not take the majority of the weight of the car.

Aftermarket wheels tend to be made with big centre bores, like 75mm. This makes them adaptable to different cars, because you buy 'hub rings'. These fit inside the centre bore, and have a cut out that suits your car. For example, if the wheel has a centre bore of 75mm, and you need a 58.1mm bore, then you add 75-58.1mm hub rings. I had these rings machined for my Enkei wheels:
http://pic20.picturetrail.com/VOL97/467659/23698212/395186833.jpg
http://pic20.picturetrail.com/VOL97/467659/23698212/395186839.jpg

Hence, to make those wheels fit your GT, you will need wobble bolts, and hub rings to suit. Any decent wheel shop will be familiar with these requirements; pretty standard affair. :)

:)
 

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Discussion Starter #17
Had a massive fail today! Halfords refuse to sell me the wheels saying they wont go on an alfa and its dangerous for them to sell them to me. Found one 17 inch original wheel on ebay ganna play it safe and go for that.
 

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Had a massive fail today! Halfords refuse to sell me the wheels
No great loss - I don't think that style would suit the GT very well. ;)
 

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Discussion Starter #19
Sorted! Wheel picked up today chhep as chips and its in better condition than the other three. Need to get the others refurbed now any ideas in the south wales area?
 
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