Wider rear tyres, Good or Bad?

[Fetta GTV]

Hi all

After some opinions on running slightly wider tyres on he rear on an 79 alfetta GTV
for example front 195/60/15 rear 215/55/15
What will this do to the handling

Cheers
Fetta GTV

[Tristan Atkins]

Hey Fetta,

Are you going to increase the width of the rear wheels also, or just place a wider tyre on the rim? Before I learn't anything about cars I got a set of 205/55/15 tyres and the car handled poorly. Straight line traction improved, but cornering dramatically decreases as the sidewall of the tyre just flexed all over the place.

The best my car ever handled was with a set of 15x7J rims running 205/50/15 all round.

It might work better just increasing the rear tyre width, but the cars weight distribution is 50/50 and the 2.0L's arn't really ever traction limited, so if the cars handling is nicely balanced, I wouldn't mess with it.

If you want more performance, I would improve the tyre compound all round by purchasing a set good quality performance tyres. After all, their the most important part of a car!

[Fetta GTV]

Tristan

Thanks for the information
My rims are 15x7 simmons
the 195s on the front are quite close to the guards while the rear have heaps of clearance
I cannot remember the exact offset of the rims
the 205s may be a bit wide on the front

Fetta GTV

[Tristan Atkins]

In that case I would go a 195/55/15 for the fronts, and 205/50/15 rear, that way the front/rear rolling diameter will be about the same.

[Fetta GTV]

Tristan

Thanks again
that sounds like the way to go
Whats a good tyre to go with?
Its an occasionally used road car, possible track day occasionally
The tyres on it at the moment are about 10 years old, still look new but are starting to show cracks between the tread

Fetta GTV

[Sheldon McIntosh]

Tristan is right, just increasing tyre width is not necessarily the way to go, and it's not like the 2.0 is lacking in traction.  The beauty of these cars is that the back end never lets go, you need to keep the neutral handling balance of the car.  I can understand that it's tempting to add width so that the car looks better, but you just have to ask yourself what's more important to you, the way the car looks or the way car drives?

Whats a good tyre to go with?

The same as always, the best you can afford.  Also, some sizes are better than others for price/range, it usually depends on what the popular cars use.  For example, I think in a 15, whatever size the MX5s use there is a great range of tyres available, but go up or down 5% and there is bugger all.

The tyres on it at the moment are about 10 years old

  Stick with them then, they'll be fine for another 5 years or so.

I don't think Alfettas are particularly sensitive to tyre choice.  Decide on what you really want do to with the car and then do a google search.  Do you want tyres that grip, or look good, or will last (but probably not ten years)?  You won't find one that will do everything, so pick wisely.

Which ever road tyre you pick it will get destroyed in one track day, two if you're very lucky.  It may seem like a luxury to have a seperate set of wheels and tyres just for track days, but it saves you money in the long run, if you're doing a few track days.

[MD]

Fetta,

For optimum handling, it is always preferable to have the rear track more narrow than the front. The idea of having fat rear tyres with a wider track than the front is for dragsters that don't go around corners.

[Fetta GTV]

Sheldon and MD

thanks for all the input
I dont want to upset the handling so I'll stick with the 195's for the moment
When they wear out I'll try to get a good set of matching tyres

Thanks again for all the info

Cheers
Fetta GTV

[Tristan Atkins]

If you want to do a track day on road tyres and not have them destroy themselves, get something with like 30% tread from somewhere like Melbournes Cheepest Tyres. New road tyres generate excessive heat due to the tread blocks deforming. Thus if you reduce the tread block size, you reduce the heat and thus extend the life of the tyre. They also have alot of 15in STI tyres, that have been traided in. Their a basic semi slick/very high performance tyre and would be perfect for your track set of wheels.