Fitted 16" fronts - results

[Chilliman]

Put the 16's on the front today (or to be accurate Rob did coz I still hade em in the boot). So, I've gone from the standard 15" Estorils to 16" Estoril's. Had new tyres fitted to the 16's yesterday, stayed with the T1R's coz the rears are good and I don't like to mix and match. Anway, thought this might be interesting for anyone else thinking about this. That said, if you search and go back a few years there's a couple of good threads about putting the 16's on the front...

So, I've gone for 16" Estorils on the front so's a) I can fit my HiSpec 300mm rotors and 4 pot calipers on (won't fit inside the 15's) and b) keep the Estorils front and back...

Here's the facts... The 15's are 7" width, the 16's are 7.5". So, to maintain rolling radius on the front, (almost but not quite), and fit a suitable tyre to the wider wheel, I've gone from 205/55/15's to 225/45/16's. So, the tyres are wider (width) with a lower profile.. So more rubber on the road, but with a correspondingly stiffer wall..The wheel offsets are also different, the outer rim being some 4mm in towards the centre of the car, so all the extra rubber is 'further in'. The result? Well, still scrubbing em in, but she tramlines significantly compared to the original setup, follows the ruts and camber far more than the 15's and so requires somewhat more driver input. Can be a bit disconcerting but it is early days.. For some strange reason it doesn't feel quite so heavy (no power steering), but grip does seem much improved, she certainly seems to turn in much quicker... I'm thinking of fitting 5mm spacers to move the rubber back out a bit, assumimg that the bells on the new brakes don't do this... I can say though, that the 16's on the front look great

Anyone else had similar experience??

Cheers all,

Chilli

[Andav469]

Chilli, I did the same change on mine a few weeks ago and went with the same tyre size and brand as yourself, my reason to change was to accommodate 324mm rotors and Brembo 4 pot calipers, however, I had to fit spacers so that the calipers didn't clash with the wheels.
I didn't want the non hub centric spacers as they nearly always lead to vibrations, the lowest hub centric you can get are 12mm, I fitted these and have no issues with tram lining whatsoever, the wheels fill the arches nicely and the car feels more planted on the road, I assume its because of the wider track.
Like you, the steering feels lighter and mine has power steering.

[tvrdavid]

Any pics? Thinking of some 16inch imolas on front of mine.

[s p a c e m a n]

What's the reasoning behind keeping the rolling radius the same as the 15in fronts?

[Andav469]

s p a c e m a n said:

What's the reasoning behind keeping the rolling radius the same as the 15in fronts?

Two points;-

- if you raise the rolling profile, it lifts the front and gives the "boat" look
- the tyre can clash with the bodywork

[SILICONEKID343HP]

These will do the trick .My old 15`s with an ET of 15 (stuck out further) seemed to drive much better.

http://www.pistonheads.com/classifieds/parts-and-p...

[Chilliman]

Andav469 said:

Chilli, I did the same change on mine a few weeks ago and went with the same tyre size and brand as yourself, my reason to change was to accommodate 324mm rotors and Brembo 4 pot calipers, however, I had to fit spacers so that the calipers didn't clash with the wheels.
I didn't want the non hub centric spacers as they nearly always lead to vibrations, the lowest hub centric you can get are 12mm, I fitted these and have no issues with tram lining whatsoever, the wheels fill the arches nicely and the car feels more planted on the road, I assume its because of the wider track.
Like you, the steering feels lighter and mine has power steering.

Hi Andav, great info Sounds like the 12mm spacers are the way to go... can you tell me where you got the hub centric spacers from? Thanks again,

Chilli

[Andav469]

Chilliman said:

Hi Andav, great info Sounds like the 12mm spacers are the way to go... can you tell me where you got the hub centric spacers from? Thanks again,

Chilli

Hi Chilli, to fit 12mm spacers, you will need to fit longer studs (very easy to do, the old studs just tap out, with plenty of room to fit the new studs without removing the hub from the car).
I bought high quality spacer kits (inc longer studs) for the front and rear, the item No on eBay is :- 271153100393

I live near Alex, next time your down, your welcome to have a go in my car and see what you think.

[SILICONEKID343HP]

Andav469 said:

Hi Chilli, to fit 12mm spacers, you will need to fit longer studs (very easy to do, the old studs just tap out, with plenty of room to fit the new studs without removing the hub from the car).
I bought high quality spacer kits (inc longer studs) for the front and rear, the item No on eBay is :- 271153100393

I live near Alex, next time your down, your welcome to have a go in my car and see what you think.

What size wheels do you have fitted ..

[Andav469]

SILICONEKID343HP said:

What size wheels do you have fitted ..

16" Estorils

[SILICONEKID343HP]

Why do you need to move your wheels 12mm further out front and rear .? The rears are perfect and the fronts only needed no more than 5mm if anything .

[Andav469]

SILICONEKID343HP said:

Why do you need to move your wheels 12mm further out front and rear .? The rears are perfect and the fronts only needed no more than 5mm if anything .

The minimum I could use was 10mm spacers, otherwise the calipers clashed with the wheel, I went with 12mm to get hubcentrics.
I spaced the rears out as well to balance it all up and after the change, it all works very well.

This pic is the set up with 10mm spacers fitted

Edited by Andav469 on Wednesday 3rd July 22:10

[glow worm]

I've got 225/45/16s Conti Sport Contact 2s on Imolas and no tramlining at all.

Try a Tuscan Convert with 255/35/18s if you want to know what tramlining is .... I tried to turn left off the M6 at Wigan and stayed on till Birmingham .

[fatboychim]

Chilliman said:

Put the 16's on the front today (or to be accurate Rob did coz I still hade em in the boot). So, I've gone from the standard 15" Estorils to 16" Estoril's. Had new tyres fitted to the 16's yesterday, stayed with the T1R's coz the rears are good and I don't like to mix and match. Anway, thought this might be interesting for anyone else thinking about this. That said, if you search and go back a few years there's a couple of good threads about putting the 16's on the front...

So, I've gone for 16" Estorils on the front so's a) I can fit my HiSpec 300mm rotors and 4 pot calipers on (won't fit inside the 15's) and b) keep the Estorils front and back...

Here's the facts... The 15's are 7" width, the 16's are 7.5". So, to maintain rolling radius on the front, (almost but not quite), and fit a suitable tyre to the wider wheel, I've gone from 205/55/15's to 225/45/16's. So, the tyres are wider (width) with a lower profile.. So more rubber on the road, but with a correspondingly stiffer wall..The wheel offsets are also different, the outer rim being some 4mm in towards the centre of the car, so all the extra rubber is 'further in'. The result? Well, still scrubbing em in, but she tramlines significantly compared to the original setup, follows the ruts and camber far more than the 15's and so requires somewhat more driver input. Can be a bit disconcerting but it is early days.. For some strange reason it doesn't feel quite so heavy (no power steering), but grip does seem much improved, she certainly seems to turn in much quicker... I'm thinking of fitting 5mm spacers to move the rubber back out a bit, assumimg that the bells on the new brakes don't do this... I can say though, that the 16's on the front look great

Anyone else had similar experience??

Cheers all,

Chilli

Hi Richard, 225/45/16 is exactly what I have on mine but with the Imola wheels. ( you saw them at Bedford on Monday) I noticed more tramlining but put it down to the DZ03G's. I haven't tried it with road tyres as I revert to the 15's for road use.
A wider track on the front may help me as I still get some understeer in tight bends.
I also found that on full lock the inner rim touches the lower wishbone, not a problem except if you forget when manoeuvring at very slow speeds, I guess a spacer would cure this as well.

[V8 GRF]

Interesting.

My experience with putting the 16" wheels on the front was the complete opposite with less understeer and less tramlining.

I haven't put spacers on the front and only needed one rackstop on the offside to stop the inside of the rim catching the lower suspension arm but I believe that is all related to how centrally your steering rack is mounted.

I have 225/50/16 on the front and my car runs lower than standard on Nitrons with slightly different camber settings than standard maybe that's the difference?

[Goaty Bill]

It does escape many people's attention, but the standard front tyre size for your 500 was 225 / 50 15, with the rears being 245/45 16.
This is in spite of anything your owner's manual says to the contrary.
The same applied to the Griffith 500s as far as I can remember.
The 400s and 450s were fitted standard with the 205s on the front.

The RG website confirms this if you look at the available tyres and descriptions.
I have to say at the same time; that I had thought that once TVR supplied power steering as standard (late '98 / '99 ?), that the 225s were to become standard for all cars. My memory could be wrong on that point though.

'Tramlining' was certainly more noticeable with the wider tyres, and when someone got away with fitting narrower tyres to mine, I noticed a difference straight away. Unfortunately it took me a couple of weeks to look closely enough recognise their mistake(?), so I ran on them until new ones were required.

[V8 GRF]

It was 225/50 for PAS and 215/50 for non PAS

[spend]

Just because wheels have the same width & OD doesn't mean they will have the same clearance inside for calipers...

The outer dimension & profile of fitted tyres will also vary greatly, you may find changing the brand of tyre for another exactly the same size suddenly either creates or solves bodywork clearance issues.

So be very careful assuming somebody elses experience will fit your situation (never minding that there may be minor variations in bodywork & its mounting)....

[fatboychim]

V8 GRF said:

Interesting.

My experience with putting the 16" wheels on the front was the complete opposite with less understeer and less tramlining.

I haven't put spacers on the front and only needed one rackstop on the offside to stop the inside of the rim catching the lower suspension arm but I believe that is all related to how centrally your steering rack is mounted.

I have 225/50/16 on the front and my car runs lower than standard on Nitrons with slightly different camber settings than standard maybe that's the difference?

Just to add that the understeer was much improved with the 16's but still apparent, however the tramlining did get worse as said though that could have been down to tyres.
Slightly off topic, does anybody find that road legal track tyres whine on the road. My Direzza's had me thinking the diff was failing first time I drove on them. Are 888's the same?

[Chilliman]

Right, using science I have worked out the following...

leaving tyre sizes aside, I can safely say that when you put 7.5" ET32 (your rear wheels) onto the front to replace your 7.0" ET25's, you move the centreline of your wheel rim 7mm closer to the centreline of the car. This means you've reduced the front track by 14mm. In addition to this, the extra .5" (call it 12mm) of the rim width means you've got an additional 6mm either side of the rim centreline, so you now have 13mm more (closer to the centreline of the car) than you had with the 15x7's. Oh, and the outside edge of the rim is one millimetre further into the arch.

So, I believe by reducing the track you also reduce the scrub radius, which is where the slightly lighter steering feel comes from.

Also, by reducing the track you're also reducing leverage on the suspension, (effectively increasing spring strength) which, I suspect, is the cause of more understeer.

So, Science tells me that 7mm spacers will put the centreline of the 16" rims, and the front track, back to where it's supposed to be.

Although, despite on paper the 15's/55 and the 16's/45 have the same rolling radius, the 16's definitely (when side by side with the 15's)looked to be about half an inch taller. If this is the case then it will raised the front end about a quarter of an inch. EDIT This suggests that both camber and steering geo are now a bit out of whack ....EDIT...

I really dunno why I did this, my front brakes are pretty good as they are

Edited by Chilliman on Friday 5th July 07:14