Westfields and 13" wheels
Westfields and 13" wheels
Author
Discussion

Lordbenny

Original Poster:

8,733 posts

241 months

Thursday 27th October 2011
quotequote all
So, Im planning on getting back into a Caterfield (dont know exactly which yet!) and am scouring the classified for a high bhp 'comfy' car.

My question is , why do the 'quick' Caterhams (R300, R400, R500 etc) have 13" wheels but when ever I look at Westfields most of them seem to still have 15" rims even though they are a similar spec to the Caterhams in terms of suspension and bhp?

Shaun_E

748 posts

282 months

Thursday 27th October 2011
quotequote all
Lighter weight (and it's unsprung, rotational weight) and a better choice of track day tyres are the 2 main reasons for 13" wheels.

Westy Pre-Lit

5,088 posts

225 months

Thursday 27th October 2011
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13's here biggrin

When I bought the car though it was running on 17's. Putting on 13's transformed the ride, handling and feel as if it was a totally different car.

I must say though that the 17's was one of the things that attracted me to the car in the first place....I feel a fool admitting that now hehe

Lordbenny

Original Poster:

8,733 posts

241 months

Thursday 27th October 2011
quotequote all
Shaun_E said:
Lighter weight (and it's unsprung, rotational weight) and a better choice of track day tyres are the 2 main reasons for 13" wheels.
I understand that but I cant understand why Westfield dont put them on their production cars and Caterham do!

jason61c

5,978 posts

196 months

Thursday 27th October 2011
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have you seen the space under the sump on the new westfields? Its about 70mm. I'm sure fitting 13" wheels would take it down to <60mm

Shaun_E

748 posts

282 months

Friday 28th October 2011
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It is almost 100% likely to be looks driven! Lets face it, 15" rims do fill the arches better. Even the Rxxx Caterhams come with 15" as standard - 13" is an option.

Lordbenny

Original Poster:

8,733 posts

241 months

Friday 28th October 2011
quotequote all
Shaun_E said:
Even the Rxxx Caterhams come with 15" as standard - 13" is an option.
Really? I dont think so...I was at Caterham 2 days ago and Callum the salesman informed me that you would 'kill yourself' if you had 15" wheels on an R500!

I wonder how a rolling radius change like this would effect the car.

Comadis

1,731 posts

245 months

Friday 28th October 2011
quotequote all
caterham challange in the past: 13inch wheels by regulations mandatory.

didnt they change it with the actual cars to 14inch ones due to better availability quality-tyres?

caterham: more focus on track (unsprung weight, smaller wheels also give a shorter final end ratio-->acceleration)

westfield: less track focused, more "consumer" focused which rather buy by appearance than by technical reasons for track-use.

Sam_68

9,939 posts

267 months

Friday 28th October 2011
quotequote all
Shaun_E said:
Even the Rxxx Caterhams come with 15" as standard - 13" is an option.
According to the 'standard equipment' specs. on their web site, it's 14" for Roadsports, 15" for the CSR, but 13" for the Supersport and R-series cars.

I think Comadis' post sums it up pretty well, but it's worth mentioning that larger diameter wheel/tyre combinations (which is very different to saying larger diameter wheels) can potentially give better ride on stty road surfaces, as the greater diameter means that the tyre 'attacks' bumps and potholes less aggressively. It depends at least as much on sidewall depth and carcass stiffness, though.

rhinochopig

17,932 posts

220 months

Friday 28th October 2011
quotequote all
The megacars, which are their track day range, did / may still do come on 13" as standard. There wasn't even an option for bigger wheels - you had minilites, image (which I spec'd) and some magnesium ones, which were ferociously expensive and not sufficiently lighter to justify their cost. All of these were 13".


Lordbenny

Original Poster:

8,733 posts

241 months

Friday 28th October 2011
quotequote all
rhinochopig said:
The megacars, which are their track day range, did / may still do come on 13" as standard. There wasn't even an option for bigger wheels - you had minilites, image (which I spec'd) and some magnesium ones, which were ferociously expensive and not sufficiently lighter to justify their cost. All of these were 13".
Yes, I noticed that, why do BEC's get 13" and car engined cars get 15"? I've seen plenty of hillclimb/sprint cars with 13"'s.

Shaun_E

748 posts

282 months

Friday 28th October 2011
quotequote all
R300 standard spec:
15" Superlight alloy wheels with Avon CR500 tyres
R400 standard spec:
15" Superlight alloy wheels with Avon CR500 tyres

Check your facts please gentlemen.
And yes I know the R500 comes with 13" but there are a lot more R300 and R400 cars on the road.

The Supersport is a new special edition which has 13" rims as part of it's "specialness".

http://www.caterham.co.uk/assets/html/showroom/sup...
http://www.caterham.co.uk/assets/html/showroom/sup...

Edited by Shaun_E on Friday 28th October 15:16

rhinochopig

17,932 posts

220 months

Friday 28th October 2011
quotequote all
Lordbenny said:
rhinochopig said:
The megacars, which are their track day range, did / may still do come on 13" as standard. There wasn't even an option for bigger wheels - you had minilites, image (which I spec'd) and some magnesium ones, which were ferociously expensive and not sufficiently lighter to justify their cost. All of these were 13".
Yes, I noticed that, why do BEC's get 13" and car engined cars get 15"? I've seen plenty of hillclimb/sprint cars with 13"'s.
Because the BECs tend to be speed first and form and practicality second, whereas the 'road cars' have a better balance of the competing requirements. The road, with full weather kit, have more mass to stop too so you could argue that they need bigger brakes - they don't - but it's all part of the marketing.

13s are always going to be lighter than 15s so it makes more sense in a predominantly track car - the best place to spend money lightening a vehicle be it bike or car is in the area of unsprung mass. They offer so many advantages: dampers have an easier job, tyres in contact with the road more, acceleration, better ride, etc.

Sam_68

9,939 posts

267 months

Friday 28th October 2011
quotequote all
rhinochopig said:
...the best place to spend money lightening a vehicle be it bike or car is in the area of unsprung mass.
Unsprung and rotational mass, of course. smile

Furyblade_Lee

4,114 posts

246 months

Friday 28th October 2011
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Benny the Hayabusa Westy on ebay looks good for £9k, but not sure about comfy :-)

anonymous-user

76 months

Saturday 29th October 2011
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No one has mentioned brakes, my sylva runs 17 inch wheels purly driven by the brake size, and there was no big deteriation in the handling in fast bends from going to 17.

Paul Drawmer

5,103 posts

289 months

Saturday 29th October 2011
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Berw said:
No one has mentioned brakes, my sylva runs 17 inch wheels purly driven by the brake size, and there was no big deteriation in the handling in fast bends from going to 17.
If a quick Caterham can get their brakes inside 13s; then if you need 17s to get the brakes in, either your car is Fing heavy, or your brakes are made of MDF.

Lordbenny

Original Poster:

8,733 posts

241 months

Saturday 29th October 2011
quotequote all
Furyblade_Lee said:
Benny the Hayabusa Westy on ebay looks good for £9k, but not sure about comfy :-)
Don't want a BEC...ideally I want a 185bhp+ engined car (2.0 Zetec or Duratec) Carbon bits, motorsport seats with upgraded harnesses, helical gearbox, motorsport wheels, decent shocks, windscreen, heater and weather gear.

Sam_68

9,939 posts

267 months

Saturday 29th October 2011
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Paul Drawmer said:
If a quick Caterham can get their brakes inside 13s; then if you need 17s to get the brakes in, either your car is Fing heavy, or your brakes are made of MDF.
^^^^ This.

You shouldn't need huge brakes to stop a Seven - particularly a Sylva (which is inherently one of the lighter types).

... Unless, of course, you're having to arrest the rotational inertia of a set of 17" wheels. wink

Kevp

587 posts

273 months

Saturday 29th October 2011
quotequote all
Sam_68 said:
^^^^ This.

You shouldn't need huge brakes to stop a Seven - particularly a Sylva (which is inherently one of the lighter types).

... Unless, of course, you're having to arrest the rotational inertia of a set of 17" wheels. wink
I think you should see Berw car & circuit 1st. But for this country I agree with 13".