NSW Corvettes

Technical Tips => Brakes, Suspensions, Steering, Wheels & Tyres => Topic started by: Jethro on May 05, 2014, 08:18:56 PM

Title: What size tires ?
Post by: Jethro on May 05, 2014, 08:18:56 PM: K,

I've ordered new Rims American Racing Rally 18" x 8" with standard back spacing i.e. 4"

http://www.americanracing.com/wheels/VN327/VN3272?year=1969&make=Chevrolet&model=Corvette (http://www.americanracing.com/wheels/VN327/VN3272?year=1969&make=Chevrolet&model=Corvette)

(http://i261.photobucket.com/albums/ii43/jetrhottracey/rally-1.jpg) (http://s261.photobucket.com/user/jetrhottracey/media/rally-1.jpg.html)

The question is what size tyres to fit?

Currently running 225/70/15 on 15 x 8" rims and want to keep the same stance so ???

(http://i261.photobucket.com/albums/ii43/jetrhottracey/09092013231.jpg) (http://s261.photobucket.com/user/jetrhottracey/media/09092013231.jpg.html)

I read on other forums that the most popular choice seems to be 245/55/18 front & 255/55/18 rears with standard off set trailing arms ???

Any actuals out there ?

Jethro
Title: Re: What size tires ?
Post by: bfit on May 05, 2014, 09:44:41 PM: Bloody big ones
Bfit
Title: Re: What size tires ?
Post by: MY081 on May 05, 2014, 09:55:39 PM: Hey Bob is that metric or imperial ?
Title: Re: What size tires ?
Post by: craigh on May 05, 2014, 10:45:02 PM: 45 not 55 profile Jethro :-)
Title: Re: What size tires ?
Post by: sabre on May 06, 2014, 05:53:30 AM: Did the maths and to keep the same rolling diameter a 255 needs a 52 profile and a 245 needs a 54. Of course actual varies with brand but between 45 and 55 is in the ball park.
Title: Re: What size tires ?
Post by: Scott on May 06, 2014, 08:25:05 AM: I use this to calc tyre sizes:
http://www.rimsntires.com/specspro.jsp (http://www.rimsntires.com/specspro.jsp)

I believe you are aiming for a 27 inch tyre height (based on 255/60-15) up to 27.4 inch (225/70-15).

255/45-18 seems on the money.
Title: Re: What size tires ?
Post by: Jethro on May 06, 2014, 02:55:28 PM: Yeah Scott great site and that's what I've been using as my Bible...

225/70/15 standard rims I'm currently running with a O.D of 697
255/45/18 has an O.D of 687

So 697 - 687 = 10mm Difference
10mm O.D I can live with :thumb:

In THEORY my new rims having a Back Spacing of 4" which is the same as my 15's and stick with the same O.D life should be sweet :nag: :nag: :nag: :nag: however Murphies Law would say not so :nag: :nag: :nag: :nag: Therefore I just need to know if anyone is running the 255's /45 / 18's on the front without and any issues :toetapping:
Title: Re: What size tires ?
Post by: bfit on May 06, 2014, 03:12:35 PM: mate
i will check what i have on my 79 and let you know
I think they are 255 60 15
bfit
Title: Re: What size tires ?
Post by: craigh on May 06, 2014, 04:20:29 PM: Quote from: Jethro on May 06, 2014, 02:55:28 PM
Yeah Scott great site and that's what I've been using as my Bible...

225/70/15 standard rims I'm currently running with a O.D of 697
255/45/18 has an O.D of 687

So 697 - 687 = 10mm Difference
10mm O.D I can live with :thumb:

In THEORY my new rims having a Back Spacing of 4" which is the same as my 15's and stick with the same O.D life should be sweet :nag: :nag: :nag: :nag: however Murphies Law would say not so :nag: :nag: :nag: :nag: Therefore I just need to know if anyone is running the 255's /45 / 18's on the front without and any issues :toetapping:

I have had the 255's on the front as a test only and I was worried they were too close to guards in turns.

I think later C3's had some changes to the guards to handle wider tyres at full lock

All depends how low U go and how much tramline effect you want.

The wider you go on the front the more tramline you will get.
Title: Re: What size tires ?
Post by: racingem on May 06, 2014, 04:40:18 PM: I have 255/45/18 on the front of my 72 and i cannot full lock because they rub. :cheers:
Title: Re: What size tires ?
Post by: bfit on May 06, 2014, 04:51:01 PM: I run
245 45 18 on my 70 model
No problems
On 18x8
Bfit
Title: Re: What size tires ?
Post by: Vettech on May 06, 2014, 06:49:26 PM: The 78 rally wheels were STD 15" and ran P255/70 R-15 front and rear whilst the pace car was fitted with mags and had P255/60 R-15 all round. For what it's worth.
Title: Re: What size tires ?
Post by: Jethro on May 06, 2014, 06:56:08 PM: Quote from: Bfit on May 06, 2014, 04:51:01 PM
I run
245 45 18 on my 70 model
No problems

Yes YES TONTO! :banghead: :banghead: 245/45 /18 fit well the Million dollar question is will 255 / 45 fit the front :toetapping:
On 18x8 with 4 " back spacings ?
Bfit
Title: Re: What size tires ?
Post by: 69 DIRTY RAT on May 06, 2014, 08:05:45 PM: I think 245s Front 255-265 rear. Back before 2005 I used to have 255's on my front but I also got rid of the inner lip so it wouldnt rub! Those wheels will look very cool!
Title: Re: What size tires ?
Post by: Jethro on May 07, 2014, 07:11:03 AM: Quote from: 69 DIRTY RAT on May 06, 2014, 08:05:45 PM
I think 245s Front 255-265 rear. Back before 2005 I used to have 255's on my front but I also got rid of the inner lip so it wouldnt rub! Those wheels will look very cool!

Thanks Andy :thumb: thats what Craig down in Canberra is running and yeah took me two years to decide these are the rims for me have to wait for them to mbe made and sent over but should be worth the wait :thumb: