MK2 Astra Offset Advise - H E L P ! ! !

[Jody Conway]

Xmas has been and gone and i got money to buy new alloys. But i dont know a damn thing about offset and dimensions or anything. I know that my wheels are 4 stud on my astra mk2, and its an E reg. Will these wheels fit?

http://cgi.ebay.co.uk/ws/eBayISAPI.d...ayphotohosting

And can someone please explain to me the whole 'offset' thing. Thankyou!!!

Jody

[Peachprformance]

There isn't enough information on the auction page to say whether they will fit or not. I've seen this sellers auctions before and he's normally selling multiple sets of the same wheel. Use the "Ask seller a question" link and give him the details of your car and he'll be able to tell you if he's got some that will fit.

The "ET" is the measurement from the back of the hub face of the wheel to the centreline of the wheel (basically chopped it in half width ways).

Where the ET measurment required then gets confusing is becuase depending on what width wheels you run alters the ET measurement required. E.G On an Mk2 Astra GTE the wheels were 6x15 with an ET of 49mm. and we'll assume that the outer edge of that wheel is sat level to the arch, and that the inner edge of the wheel is 1" away from the strut.

Now if you increase the width of that wheel to 7" but leave the offset at 49mm the wheel will stick out from the arch by a 1/4 of an inch and be 3/4 inch away from the strut. Now a 1/4 of an inch in mm is 6.35mm so in order to get the wheel to sit in the correct place in relation to the arch the ET (offset) for the new 7x15 wheel would be 49mm - 6.35mm = 42.65. The Wheels outer edge is now level with the arch again and the inner edge is now 1/2 inch away from the strut. Please remember that this is just an hypothetical example and not the offset you would require.

This also throws up the problem that an identical wheel in 6.5x15 will go under a piece of piss, a 7x15 would, a 7.5x15 should just and a 8x15 won't in a month of Sundays. So the diameter of the wheel is not the overiding factor. However if the 7.5" wheel was 17" in diameter and the rolling radius with the tyre had increased slightly you may now find yourself scrubing the inner arch or suspension strut. So now diameter has come into play as well.

Unfortunately this is why no one you speak to will gurantee what size wheel will fit your car but will recommend on personal experience's on what they know has fitted in the past. This is also why there is no deffinative ET for aftermarket wheels where the size is different from the Manufacturers original size.

[evomaster3000]

rochford tyres are good, chances are these wheels are ford fitment and et35 as these are most common and also they are on special offer, but email them and they will tell u if they have ones in that style to fit, alternativly go to thier website which has a search facility which is car specific, www.rochfordtyres.co.uk i think

[evomaster3000]

basicially when buyin wheels, 4x100 pcd, ET49 or ET45, 17's are the max u will get on a mk2

[Vauxpartz]

et49 only ,for me.

[remus]

you can get 18's on a mk2, a guy "itsnotamerit!" has them on his mk2.

[Mark T]

you can get 19s on if you pay enough for skinny tyres.

[evomaster3000]

Ok but w/o serious arch work!