Who doesn't like big wheels?

Who doesn't like big wheels?

Author
Discussion

InductionRoar

2,001 posts

131 months

Thursday 4th September 2014
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robinessex

11,046 posts

180 months

Thursday 4th September 2014
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Guys. The spring rate the car 'sees' is the spring rate of the suspension spring, and the radial stiffness of the tyre wall. This spring rate is what you feel as you drive along. Mathmaticaly, it's 1/k = 1/k1 +1/k2 i.e. the reciprical of the total spring rate is the sum of the reciprical of the two elements comprising that stifness, the spring and tyre radial stiffness. Now, obviously, if you substitute a lower profile tyre, that will increase the spring rate of that component, thus the suspension spring will need to be changed (lower actually) to get back to the original value of the composite spring. And the dampers will need their settings changed as well.

vikingaero

10,256 posts

168 months

Thursday 4th September 2014
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Several motoring shows have done track time comparisons with cars with standard wheels and cars with phat alloys. In every case the standard wheels posted quicker lap times.

However J.Public still generally believes that phat wheels will make a car corner quicker, go faster and get them laid more often.

Wills2

22,666 posts

174 months

Thursday 4th September 2014
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juansolo said:
Wills2 said:
Oh and you can't get 21" Porsche wheels for the 981/991 gen cars biggest available are 20".
surely only a matter of time though...
Probably!

Frankthered

1,619 posts

179 months

Thursday 4th September 2014
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MRobbins1987 said:
Axionknight said:
A few weeks ago a friend and I scooted off into the Highlands in our cars, for a weekend of fun - he has a Civic Type R, FN2, on factory option 19" alloys, and on the bumpy, rutted backroads they really made things hard work, the ride was so st that it really dented any confidence I had in the car when we swapped motors, he felt the same will be swapping them out asap

Depending on the application, I do like 'em, but for pressing on and having fun on our crappy British B roads, nah, they aren't good enough.
Mine came with 19's horrible things, I swapped for some lighter 18's still horrible, best option is 17's with new suspension or a better car...
The ride was probably the worst feature of the FN2 Civic. I had a regular cooking 1.8 "Sport" version, which meant it got 17" wheels. I often wished I had bought a version with 16" instead. The ride would never be great, but it would be better with smaller wheels.

I think the point that's been missed a little on this thread is that, when a car is designed, it will be done with a particular wheel and tyre size combination in mind - possibly even a specific tyre to suit the ride/handling that the designer is aiming for. So if something different is used it will compromise something. Of course, it's possible for the suspension to be redesigned to accommodate the different size of wheel, but I don't think you will get that when you specify dealer option big wheels on your car! And you will usually compromise the ride.

Similarly, if you fit smaller wheels than the ideal, you will probably still improve the ride but you'll probably compromise the handling.

It's all a compromise though, isn't it?

MC Bodge

21,551 posts

174 months

Thursday 4th September 2014
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Steel wheels with tyres that have air cushioning and grip on real roads are where it is at

rolymo

595 posts

198 months

Thursday 4th September 2014
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Back at the dawn of motoring in the pre world-war II era of the 30's the designers pretty much agreed that if you wanted sporty cars then big/skinny wheels was the right way to go. Leap from one pot-hole to the next on small spidery country lanes at fantastic speeds, all of 75 mph if you were lucky. Just look at this fine example of every young mans desire :-

rolymo

595 posts

198 months

Thursday 4th September 2014
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The following year (1937) MG decided that it would be a good idea to follow the same theme but inclued fresh air ventilation , just note those big long-legged wheels, This model would go on to be the favourite "Flash" of our RAF battle pilots MG TA (2 Seat) sports

braddo

10,399 posts

187 months

Thursday 4th September 2014
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jamieduff1981 said:
It has nothing to do with the wheel and tyre size. I own both an X-Type with 18" wheels and 40 profile tyres, an S-Type with 18" wheels and 40 profile tyres and an XF on 20" wheels and 30 profile tyres. I previously had an X-Type on 17" wheels and 45 profile tyres.

The S-Type chassis is simply all-round vastly superior to the X-Type chassis in terms of ride quality. Simple as that. Going from 17" X-Type to 18" S-Type was a massive improvement in ride. The 18" X-Type came after getting used to the S-Type's ride and feels a bit harsh - but I remind myself of how impressed I was with the S-Type's ride I was in the first place that motivated me to change.

The XF is rather stiffly sprung but rides on forged wheels which aren't as heavy as they might be. It's very firm, but not crashy or harsh. But it has adaptive dampers which helps.
Bullst; apples and oranges.

Smaller wheels will almost always give a lower unsprung weight than larger wheels. This is a handling benefit that cannot be fully compensated for by simply changing spring/damper rates. Thus, your XF on 18 inch wheels would handle and ride better than on its current 20s.


Kawasicki

13,041 posts

234 months

Thursday 4th September 2014
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Why do bigger wheels (and the correspondingly lower sidewall heights) tend to improve handling stability in fast direction changes?

Do you think an Astra on 205/50R16 will be as capable though an emergency lane change as the same Astra on 245/30R19?

boxerTen

501 posts

203 months

Friday 5th September 2014
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Kawasicki said:
Why do bigger wheels (and the correspondingly lower sidewall heights) tend to improve handling stability in fast direction changes?

Do you think an Astra on 205/50R16 will be as capable though an emergency lane change as the same Astra on 245/30R19?
Lower sidewall heights allow the wheel to control the shape of the tyre better making it better able to stay properly in contact with the road under high load.

Also worth mentioning: a wider tyre can be made of softer compound for the same amount of durability since the tyre physically has a greater surface area to wear away. Less well understood is that this is also true of larger diameter tyres.


rolymo

595 posts

198 months

Friday 5th September 2014
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What goes around comes around !. Whats not to like about big wheels ? this Good old Viva will never be the same !

ChemicalChaos

10,360 posts

159 months

Friday 5th September 2014
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irocfan said:
to be honest I quite like big wheels - as an example.



IMO smaller wheels just wouldn't look right (though I'll agree the rear could do with being a little lower) and ride comfort is fine (as long as I steer past potholes)
I'm sorry but no, muscle cars need big squishy donut tyres!





The ridiculous bling pandering of designers trying to ape the tasteless chavs that put monster rims on their cars needs to stop as well. I wonder how many people would spec the stupid wheels if you showed them a table of tyre cost vs size when purchasing the car, or how much a 20" wheel costs to replace/refurbish, or how few tyre garages can fit a really low-profile tyre.

As well as being vastly more comfortable, a tall tyre is far more proressive and communicative when driving normally (no on-track limit-of-grip treadshuffle bks here) as you can feel it being to roll under in tight corners on b-roads, instead of just suddenly skidding like a stiff tyre would

djc206

12,241 posts

124 months

Friday 5th September 2014
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I know that on my car the smallest wheels that would fit over the front brakes are 19's. Not liking the style of 19's available I went for 20's. I also think that on the vast majority of cars bigger wheels look better by filling the arches a bit more. Muscle cars, old pickups and 4x4's excepted of course.

irocfan

40,152 posts

189 months

Friday 5th September 2014
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ChemicalChaos said:
The ridiculous bling pandering of designers trying to ape the tasteless chavs that put monster rims on their cars needs to stop as well. I wonder how many people would spec the stupid wheels if you showed them a table of tyre cost vs size when purchasing the car, or how much a 20" wheel costs to replace/refurbish, or how few tyre garages can fit a really low-profile tyre.
here's the thing though - my 20's actually cost less than the 18's I was thinking of....

oh and thanks for calling me a tasteless chav wink

MC Bodge

21,551 posts

174 months

Friday 5th September 2014
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The other week I saw 2 2-door Audi A5s (the ones that remind me of Mustangs) on the motorway. One was on relatively small wheels with few external bells and whistles. The other was the full S-LINE, macho, girders for springs, cartoon caricature model on enormous rims with LOW tyres.

Looks are not really important, but I actually preferred the more discrete one with some tyre wall showing.

kambites

67,460 posts

220 months

Friday 5th September 2014
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ChemicalChaos said:
I've never seen a modern Mustang on small wheels before, that looks really rather nice. smile

jamieduff1981

8,022 posts

139 months

Friday 5th September 2014
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braddo said:
jamieduff1981 said:
It has nothing to do with the wheel and tyre size. I own both an X-Type with 18" wheels and 40 profile tyres, an S-Type with 18" wheels and 40 profile tyres and an XF on 20" wheels and 30 profile tyres. I previously had an X-Type on 17" wheels and 45 profile tyres.

The S-Type chassis is simply all-round vastly superior to the X-Type chassis in terms of ride quality. Simple as that. Going from 17" X-Type to 18" S-Type was a massive improvement in ride. The 18" X-Type came after getting used to the S-Type's ride and feels a bit harsh - but I remind myself of how impressed I was with the S-Type's ride I was in the first place that motivated me to change.

The XF is rather stiffly sprung but rides on forged wheels which aren't as heavy as they might be. It's very firm, but not crashy or harsh. But it has adaptive dampers which helps.
Bullst; apples and oranges.

Smaller wheels will almost always give a lower unsprung weight than larger wheels. This is a handling benefit that cannot be fully compensated for by simply changing spring/damper rates. Thus, your XF on 18 inch wheels would handle and ride better than on its current 20s.
You've missed the point by a large margin.

The point is that by far the main reason that poster's 17" wheel shod XF rides far better than his 18" wheel shod X-Type is because the XF is a refined derivative of the S-Type chassis which already had a vastly superior ride quality than the X-Type did even on like-for-like wheels.

The perceived difference therefore is:

Vast majority superior car versus tiny minority drop in wheel size.

jamiehamy

360 posts

175 months

Friday 5th September 2014
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I don't like big wheels.

My Corrado G60 came with horrendous 17s and when I swapped to 15inch Superleggeras, the whole car was trensformed - the braking, handling and acceleration.

Same when I got my VR6. It now runs on 16's (because I have TT brakes) with 205 50 16 tyres. Soaks up the bumps, handles brilliantly as well as able to take a battering from potholes.

I would add that I got rid of the aftermarket lowered springs and stty shocks replacing with standard springs on Bilsteins. Gorgeous setup to drive. Loads of ride height which is great in snow(!) and unmade tracks,lots of travel on our very undulating back roads, can drive on poor roads at a good speed without getting flung everywhere.

And as for gears - the Corrado is 5 speed which is awesome! None of this short ratios, never quite finding a log enough gear nonsense smile

8bit

4,846 posts

154 months

Friday 5th September 2014
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HertsBiker said:
8bit, sorry, I didn't realise there was a similar thread. I watch PH every day and hadn't noticed or I'd have contributed to that. Not trolling. Why'd you say that? I seem to be very misunderstood.
Fair enough, the problem with General Gassing is it's so busy that unless you go through all the new threads it's easy to miss stuff. Re. trolling, maybe I was a bit harsh, just the tone of your original post sounded like you were starting some moral crusade against large wheels combined with the fact that there'd been threads like this recently.