Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: Stagecoach on 25 October 2010, 09:31:27

Title: Tyres
Post by: Stagecoach on 25 October 2010, 09:31:27: Hi. My car has 225/55/16's. I have been offered cheap a pair of 205/55/16's. Will they fit.

Cheers Guys
Title: Re: Tyres
Post by: Omega_Dan on 25 October 2010, 09:34:49: I dont think so? the section width is quite a bit less. wouldn't risk it anyway :y
Title: Re: Tyres
Post by: cem_devecioglu on 25 October 2010, 11:08:01: apart from the insurance problem stated by other members in that thread
http://www.omegaowners.com/forum/YaBB.pl?num=1287911392

personally I wont advice.. miggy is a heavy car and definitely you wont be safe on curves .. but will fit..

also you will need speedo correction by tech 2 as the tire diameter of 225 and 205 seriously different..
Title: Re: Tyres
Post by: Diamond Black Geezer on 25 October 2010, 11:27:54: Hmmm...As stated on the other thread (-link provided above) and I was the one saying that you'd be ok with 215s - however I think 205 is starting to push it a bit. Rolling radius would be different, cem is quite correct, so speedo will be out

(just done a quick calculation and I make the speedo will be out by 8.8%, though someone with better maths skills than I may give a completely different figure!) So indicated 91.1mph @ actual 100mph (my brain hurts)

As you have an Elite that means you have 7.5J x 16 wheels(?) as opposed to the 7Js that a 205 would run on. So thats nearly an inch NARROWER tyre running on a half-inch WIDER rim.

There are the facts, go forth my son, and do with them what you wish! :y
Title: Re: Tyres
Post by: Diamond Black Geezer on 25 October 2010, 11:30:37: Oh course if these are decent rubber it may well be worth your while sourcing some cheap lower-spec alloys? ie: those designed for 205 rubber. Again, as cem says the speedo will still be out. Depends if you dont mind people thinking you own a CD, instead of and Elite (are people that pedantic where you live?)
Title: Re: Tyres
Post by: bluey on 25 October 2010, 12:07:22: Sounds to me that you'd in in danger of spending £50 to save a tenner. Better to just stick to the correct spec.
Title: Re: Tyres
Post by: Psychoca on 25 October 2010, 12:45:00: Quote
apart from the insurance problem stated by other members in that thread
http://www.omegaowners.com/forum/YaBB.pl?num=1287911392

personally I wont advice.. miggy is a heavy car and definitely you wont be safe on curves .. but will fit..

also you will need speedo correction by tech 2 as the tire diameter of 225 and 205 seriously different..

Learn something new every day... I always thought that the profile dealt with the tyre diameter and the tread width the tyre width...

I have thought of changing the tread width of mine to 225 from 205 ('98 GLS spec)...
Title: Re: Tyres
Post by: aaronjb on 25 October 2010, 12:54:22: Quote
Quote
apart from the insurance problem stated by other members in that thread
http://www.omegaowners.com/forum/YaBB.pl?num=1287911392

personally I wont advice.. miggy is a heavy car and definitely you wont be safe on curves .. but will fit..

also you will need speedo correction by tech 2 as the tire diameter of 225 and 205 seriously different..

Learn something new every day... I always thought that the profile dealt with the tyre diameter and the tread width the tyre width...

I have thought of changing the tread width of mine to 225 from 205 ('98 GLS spec)...

Well.. they do ;) But since profile is expressed as a percentage of width, they're related..

So if you drop the width, you'd need to increase the profile to keep the rolling radius the same - this site gives a reasonable approximation of the calculation:
http://www.miata.net/garage/tirecalc.html

(Real world being a bit different due to squish and so on, IIRC)
Title: Re: Tyres
Post by: Psychoca on 25 October 2010, 13:24:15: Yeah, I found one of those... Just means that I need to change 2 tyres next time instead of just the 1...