Help with 930 front tyres
Help with 930 front tyres
Author
Discussion

RVVUNM

Original Poster:

1,913 posts

239 months

Friday 9th November 2012
quotequote all
I am in need of replacement front tyres and wondered who's running what on their car. Currently I have Pirelli tyres (not been good) that are 225/45/16, now I know this is the wrong size and really should be a 55 profile but there is conflicting info as to the correct size. Should they be 205,215,225?

D900SP

459 posts

213 months

Friday 9th November 2012
quotequote all
Correct size for standard 78-89 911 Turbo front tyre is 205/55/16, with the rears at either 225/50/16 for 8" rear wheels or 245/45/16 for 9" rear wheels.

I'm wondering how old the 245/45/16 Pirelli tyres are.

supersport

4,637 posts

257 months

Friday 9th November 2012
quotequote all
I use Continental Sport Contacts, which happen to be N rated but this is not required, they are the 205x55x16 size.

RVVUNM

Original Poster:

1,913 posts

239 months

Friday 9th November 2012
quotequote all
D900SP said:
Correct size for standard 78-89 911 Turbo front tyre is 205/55/16, with the rears at either 225/50/16 for 8" rear wheels or 245/45/16 for 9" rear wheels.

I'm wondering how old the 245/45/16 Pirelli tyres are.
They are from 2004 which is why im changing them.

mudy

874 posts

202 months

Sunday 11th November 2012
quotequote all
Contis have always been good for me - 205/55 ZR 16

nsa

1,704 posts

258 months

Monday 12th November 2012
quotequote all
If you're using 7" or 8" wide front wheels you can use 225/45/16 tyres. This will give you a wider footprint and slightly lower profile than standard. I've used them on 7" wheels on road and track with no problems.

205 or 215 are probably standard though and for those you will need 50 or 55 profile. Just calculate the tyre width and height =

45% of 225 is 101.25mm
50% of 215 is 107.50mm
50% of 205 is 102.50mm

etc. All you're doing is getting to an approximation of the original tyre width and height. I think the skinny tyres on the front are just one way to lighten the steering and set the car up to understeer.

I got stuck in France for a week while I sourced two tyres identical to original spec on the misguided belief that I couldn't tweak it slightly.

You may want to stick to spec just to make sure your speedo is still correct for the circumference of the tyre. Mine is a track car with GPS speedo so not applicable in my situation.

RVVUNM

Original Poster:

1,913 posts

239 months

Monday 12th November 2012
quotequote all
Currently the car understeers badly on the Pirelli's. I want to go back to standard so will probably go for Conti's.

nsa

1,704 posts

258 months

Monday 12th November 2012
quotequote all
If the tyres are eight years old the rubber will be rock hard and have reduced grip.

RVVUNM

Original Poster:

1,913 posts

239 months

Monday 12th November 2012
quotequote all
nsa said:
If the tyres are eight years old the rubber will be rock hard and have reduced grip.
Good point, but they have always been bad tyres.

mudy

874 posts

202 months

Monday 12th November 2012
quotequote all
The contis are a good tyre with no undue understeer

D900SP

459 posts

213 months

Monday 12th November 2012
quotequote all

Getting matching (brand, model and specification) tyres in standard sizes if the rears are 245/45/16 is difficult. I believe only Toyo and Bridgestone currently make the 245/45/16 with matching fronts.

SEE YA

3,522 posts

275 months

Tuesday 13th November 2012
quotequote all
+1
mudy said:
The contis are a good tyre with no undue understeer

supersport

4,637 posts

257 months

Tuesday 13th November 2012
quotequote all
D900SP said:
Getting matching (brand, model and specification) tyres in standard sizes if the rears are 245/45/16 is difficult. I believe only Toyo and Bridgestone currently make the 245/45/16 with matching fronts.
Continental do too, from the Camskill website:

Continental Tyres / Car / Continental ContiSportContact Continental Conti Sport Contact - 205/55 R16 Z (N1) FR TL - £64.20

Continental Tyres / Car / Continental ContiSportContact Continental Conti Sport Contact - 245/45 R16 Z (N1) FR TL - £123.70

RVVUNM

Original Poster:

1,913 posts

239 months

Tuesday 13th November 2012
quotequote all
Thanks chaps, Conti's are the way forward then.

lindsayhbrown

173 posts

231 months

Tuesday 13th November 2012
quotequote all
I'm a bit late I know, but I have contis all 'round on my '86 SSE and have had no issues so would recommend them