Omega Owners Forum
Omega Help Area => Omega General Help => Topic started by: hoody on 01 October 2008, 22:08:00
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Are they a direct fit onto the omega and can you use the wheel bolts already fitted to the omega?
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yes and yes
5x100 fitment
people have said it makes a difference if front wheel drive but i dont think it does, but you will have to change the tyre size to keep your speedo reading within legal limit
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yes and yes
5x100 fitment
people have said it makes a difference if front wheel drive but i dont think it does, but you will have to change the tyre size to keep your speedo reading within legal limit
I think the point being made about using FWD wheels on an Omega is that the ET ie offset is different. I can never remember which way the numbers work, but you run the risk of the tyre being further back under the arch & so closer to the struts & shockers/dampers and therefore might rub against them. :y
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yup they will fit, i think its 5x110 & the offset you can get away with is 35-45 :y
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look here,,,http://www.carlsalter.com/wheel_fitments.html
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yes and yes
5x100 fitment
people have said it makes a difference if front wheel drive but i dont think it does, but you will have to change the tyre size to keep your speedo reading within legal limit
Surely as the car has wheel speed sensors mounted on each wheel. the speedo in theory can never be reading anything other than an actual speed?
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i always thought the speedo worked via the g/box final drive so is reliant on the correct overall diameter of the wheel & tyre, but if as you suggest it has wheel sensors for speed sensing then would it not run off the hub so would still rely on the correct wheel size?, maybe im wrong as im not familiar with the wheel sensor arrangement but im sure somebody will educate us all ;)
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Lol.....the speed is derived from the rear ABS sensors (which is sensible as it means its after the various gearbox and diff ratios available).
But, of course it will be affected by different tyre sizes as the tyre circumference will change.
With Tech2 you do program config data into the
MID and speedo to allow it to compensate for wheel size.
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taking the wheel size as OEM wheels/tyres 225/55/16, then replacing with 225/40/19's will make your wheel speed 1.3% slower - ie. when your speedo reads 60mph, actual travelling speed will be 60.8 mph - this is about the closest youll get :)
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spacers will cure the offset difference, and the speedo reading is taken from a part that doesnt change size, so if you were to put (forgive the exaggeration) 40" wheels on a car, the speedo reading will still say 30 when the car's more likely doing 50 because of the huge rolling circumference of the tyres
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could be useful as a guideline as to what offset the original miggy wheels are, also the width [?J] itll give a rough idea as to what tyre sizes could be used on what wheels,,,,anybody??
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so how much of a difference would it make if they were 215/50/17?is it negligible or would it throw it out a mile?it sits at the moment on 225/55/16.
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yes and yes
5x100 fitment
people have said it makes a difference if front wheel drive but i dont think it does, but you will have to change the tyre size to keep your speedo reading within legal limit
sorry i meant 5 x 110 :y
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My car is running on Vectra C 19" wheels. The original Miggy wheels were offset differently by 7mm. ET38 vs. ET45. The bigger the number (in mm) the more "inward" the wheel is set. FWD tend to need a larger ET number (more inward wheels on the hub)
They are spaced with hub-centric Eibach spacers as follows:
([size=12]DO NOT USE NON HUB-CENTRIC [/size]as the wheel bolts will then be supporting the weight rather than just pulling the wheel to the hub. The sticky out bit in the middle of the spacer needs to be the right size, but the vendor will advise for the wheel to be fitted. Similarly the countersunk bit in the middle of the back of the spacer needs to be matched to the sticky out bit of the car's hubs)
This size matters as much as bolt spacings and offset as it is important that the countersunk inside of the wheel fits snugly against the stub which sticks out of the hub. (roughly 2" in diameter).
Front spacers: 18mm each corner; net effect is 10mm further out each corner or an increased track of 20mm.
Rear spacers: 25mm each corner; net effect is 17mm further out each corner or an increased track of 34mm.
The car sits more planted now, and the wheels fill the arches slightly better. It does not sit proud, does not wobble at any speed and handles very well (I have new MV6 springs and struts all round)
Tyres It doesn't really matter where you start as, I believe, some cars have narrower tyres than others, but the profile is adjusted to compensate so that they all have pretty much the same starting point rolling radious regardless of modals (I may be very wrong here, but that link above will help you calculate what size you should go for and as metnioned you can adjust the speedo with a Tech2).
My original 17" Elite wheels were fitted with 235x45x17 and my new wheels are fitted with 235x35x19.
When I replace my rear tyres I will be fitting 265x30x19.
(http://farm4.static.flickr.com/3106/2620873480_d75b0ca31e.jpg)
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so how much of a difference would it make if they were 215/50/17?is it negligible or would it throw it out a mile?it sits at the moment on 225/55/16.
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it will be 1.1%fast - when speedo reading 60mph you will actually be travelling at 59.3 mph
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Standard tyres on 17" wheels is 235x45x17 (At least for an Elite / MV6 facelift anyway)
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so how much of a difference would it make if they were 215/50/17?is it negligible or would it throw it out a mile?it sits at the moment on 225/55/16.
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it will be 1.1%fast - when speedo reading 60mph you will actually be travelling at 59.3 mph
to clarify, the legal limit of difference is that it must be within 2.5%, so this is fine :y
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yup they will fit, i think its 5x110 & the offset you can get away with is 35-45 :y
I just tried some Vectra C 16 inch alloys on my Omega. They seem to sit a bit "in", which would be cured with spacers (illegal I think). About offset /ET figures: Omega steel rims ET 33, 16 inch Omega alloys ET 39 and the Vectra ones ET 41 Funny, how ET39 looks very much better that ET41...
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yup they will fit, i think its 5x110 & the offset you can get away with is 35-45 :y
I just tried some Vectra C 16 inch alloys on my Omega. They seem to sit a bit "in", which would be cured with spacers (illegal I think). About offset /ET figures: Omega steel rims ET 33, 16 inch Omega alloys ET 39 and the Vectra ones ET 41 Funny, how ET39 looks very much better that ET41...
Suitably fitted and approriate hub-centric spacers are not illegal. My car passed its M.O.T. today with them fitted no problems.
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yup they will fit, i think its 5x110 & the offset you can get away with is 35-45 :y
I just tried some Vectra C 16 inch alloys on my Omega. They seem to sit a bit "in", which would be cured with spacers (illegal I think). About offset /ET figures: Omega steel rims ET 33, 16 inch Omega alloys ET 39 and the Vectra ones ET 41 Funny, how ET39 looks very much better that ET41...
Suitably fitted and approriate hub-centric spacers are not illegal. My car passed its M.O.T. today with them fitted no problems.
They probably didn't know they had been fitted as they aren't allowed to dismantle anything.
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yup they will fit, i think its 5x110 & the offset you can get away with is 35-45 :y
I just tried some Vectra C 16 inch alloys on my Omega. They seem to sit a bit "in", which would be cured with spacers (illegal I think). About offset /ET figures: Omega steel rims ET 33, 16 inch Omega alloys ET 39 and the Vectra ones ET 41 Funny, how ET39 looks very much better that ET41...
Suitably fitted and approriate hub-centric spacers are not illegal. My car passed its M.O.T. today with them fitted no problems.
They probably didn't know they had been fitted as they aren't allowed to dismantle anything.
Yes they did because I was there the whole time and I pointed them out when he asked about my 19" wheels.
They are defnitely legal; I checked when I bought them.