GolfGTIforum.co.uk
Model specific boards => Golf mk7 => Topic started by: Burger81 on 16 March 2018, 19:01
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Just fitted 19’s on my GTI after swapping the 18” Austin’s.
Car feels noticeably slower, physics say it should, but unless most of it’s in my mind it really feels different!
Car is running stage 1 Revo, and I swear engine noise seems quieter too, not as grunty as before.
Anyone else experienced this weirdness?
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What size tyres? If you've increased the circumference of the tyres that would go some way to explain it. Also what wheels? If they're heavier that won't help either.
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Tyres are now 235/35. So wider by a cm a tyre. Alloys are 10kgs a rim so lighter than the Austin.
Car has also been lowered too.
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This is from the VW price list:-
"Choosing larger alloy wheels than standard, as an option, may result in increased fuel consumption as well as higher CO2 emissions and subsequently increased Vehicle Excise Duty (VED) band, and BIK rates paid by company car drivers may increase. This is due to the fact that larger wheels have both more aerodynamic drag and more mechanical drag, resulting in increased rolling resistance and increased wind resistance. As a result, the VED band that the vehicle falls into may increase from its original VED band when fitted with standard size wheels. In some instances, the recommended ‘On the road’ retail price paid for the vehicle may increase as a result of the increased VED rate."
:sad:
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Funny you say that because that’s why my car came with the 18’s because the 19’s couldn’t go with on a car with the sunroof as the sunroof and the 19’s together were both affecting the aero and drag.
Just the 19’s without the sunroof or just the sunroof and 18’s were ok though.
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I wouldn’t think aero would be any different due to the wheels. I bet the weight of the sunroof adds up though.
There was a 5 door edition 40 demo locally with sunroof, DSG and that had Pretoria’s and cup 2 tyres unless they put the wheels on themselves.
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The salesman told me that’s why golfs with sunroofs don’t come with the 19’s unless specced specifically.
Still I can’t believe how much slower my car feels with bigger wheels and wider tyres.
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Strange cos I took my pret’s off and fitted Audi TT 17’m wheels with same width tyres and overall diameter is the same and if anything it feels slightly slower with the 17s cos they’re way heavier.
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I remember putting my 14" steel wheels back on my Astra from its 17" Kahn RSR wheels and its transformed into a rocketship.
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Yes you only have 19" for the looks! ;). And if you av realy bigg brakes ..
i have only 17" on my semi slicks for track use! :grin: Fast, cheap and ugly!!.. :grin: :grin:
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Was about to pull the trigger on a set of 19" V1s weighing 24lbs to use as my main, summer set but this thread has got me really worried. 24lbs isn't the heaviest wheel out there, for reference Leon Cupra Sub 8 19" wheels weigh in at 26lbs after all. However the stock 18" Belvedere wheel of the Clubsport is a forged ultra lightweight wheel weighing in at a mere 16.8lbs, so I'm going up 40% in weight and I imagine it will be quite noticeable?
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I went from 18" Austins to 19" MOMO Revenge alloys and definitely less economical. Speed wise, can't say I've noticed much but perhaps now you mention it...
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I went from standard 18" Nogaro to 19" Santiago and the only difference I felt was lack of grip on the Pirelli tyres.
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According to this tyre size calculator, (http://www.tyresizecalculator.com/tyre-wheel-calculators/tire-size-calculator-tire-dimensions) by fitting 235s you are gearing up by 1.6%. If you had fitted 225/35/19s, you would only have geared up by 0.5%.
No idea how this contributes to your feelings with the car, but it will make a difference. As said, the increased rotating mass is the main factor.
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A 235/35 19 tyre has about 7mm greater diameter than a 225/35 19 (3.5mm deeper tyre wall x 2 sides).
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I fitted 235/45/17 on in place of 235/35/19 and the dieter etc is near as dammit the same. 0.5% speedo error.
Car feels very slightly slower on the 17s as they’re very heavy compared to the Pretoria’s though it’s probably in my head.
(https://s10.postimg.org/o40dpzgax/5_BE76_E1_E-7_DD2-42_A6-_A97_B-2_C3_F527_D436_B.png) (https://postimg.org/image/85rnzum2t/)
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I went from standard 18" Nogaro to 19" Santiago and the only difference I felt was lack of grip on the Pirelli tyres.
Both use the same 225 width tyre do you shouldn't have noticed anything really.
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Good article in Top Gear magazine this month (I didn't buy it), saying that making us hanker after bigger wheels is a massive con by marketing executives. If you look at high performance cars from 20 years ago, I think he used a BMW as an example, the ride was way better back than, as it had smaller wheels and bigger tyres than the current models. Another example was a F1 car, small wheels, chunky tyres. I tend to agree, as the ride in Mk5 on 17s was way better than the ride in my Mk7 on 18s. You live and learn.
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I actually prefer my GTD on 205 55 16 winters over the 225 40 18 summers, at least in terms of ride comfort.
Makes a massive difference on the pothole ridden Oxforshire roads.
Also feels quicker on the 16" wheels, probably because they have a lot less intertia (the 16" are lighter).
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I actually prefer my GTD on 205 55 16 winters over the 225 40 18 summers, at least in terms of ride comfort.
Makes a massive difference on the pothole ridden Oxforshire roads.
Also feels quicker on the 16" wheels, probably because they have a lot less intertia (the 16" are lighter).
I run 17” wheels in the winter shod with winter tyres which are a softer compound, and like you the ride is definitely more comfortable than my 18’s
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40 Profile rubber is optimum for comfort and handling.
19” wheels on a Golf only look good when the car is approached from ‘square on’ ( perpendicular? ) but from most other angles 19” on a Golf look too big.
Prets ‘slightly’ buck this trend because of their ‘delicate’ design but the standard 19” Cadiz forced on ROI Golf R customers look ham fisted and ‘heavy’..
If the GTI and R are ‘everyday, all purpose, do everything cars’ they do not need 35 profile rubber.!
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I will do a video to compare how much slower the 19" against the 17"
With this awsome thing
https://www.stertman.se/tillbehor-bankorning/3899-p-gear-p600.html
Sub to my channel if you want to know how bad the 19" are.. :sad:
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Even though it does feel a tad slower I’m glad I did it as it looks 100% better.
No arch gap, wheels fill the arches. Wouldn’t change it back at all.
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I will do a video to compare how much slower the 19" against the 17"
With this awsome thing
https://www.stertman.se/tillbehor-bankorning/3899-p-gear-p600.html
Sub to my channel if you want to know how bad the 19" are.. :sad:
Have you bought that already?
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Good article in Top Gear magazine this month (I didn't buy it), saying that making us hanker after bigger wheels is a massive con by marketing executives. If you look at high performance cars from 20 years ago, I think he used a BMW as an example, the ride was way better back than, as it had smaller wheels and bigger tyres than the current models. Another example was a F1 car, small wheels, chunky tyres. I tend to agree, as the ride in Mk5 on 17s was way better than the ride in my Mk7 on 18s. You live and learn.
f1 use the chunky tyres for suspension
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I will do a video to compare how much slower the 19" against the 17"
With this awsome thing
https://www.stertman.se/tillbehor-bankorning/3899-p-gear-p600.html
Sub to my channel if you want to know how bad the 19" are.. :sad:
Have you bought that already?
Yes :grin:, will do a review of it. Think it is a interesting device :wink:
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I will do a video to compare how much slower the 19" against the 17"
With this awsome thing
https://www.stertman.se/tillbehor-bankorning/3899-p-gear-p600.html
Sub to my channel if you want to know how bad the 19" are.. :sad:
Have you bought that already?
Yes :grin:, will do a review of it. Think it is a interesting device :wink:
Argh... too late! Had another suggestion around half the price for you.
I have another such device myself (not the one I had in mind for you) and love it for comparing all changes I do to the car, as well as logging my track times. Does P600 offer track maps and track logging apart from the straight line accelerations?
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I will do a video to compare how much slower the 19" against the 17"
With this awsome thing
https://www.stertman.se/tillbehor-bankorning/3899-p-gear-p600.html
Sub to my channel if you want to know how bad the 19" are.. :sad:
Have you bought that already?
Yes :grin:, will do a review of it. Think it is a interesting device :wink:
Argh... too late! Had another suggestion around half the price for you.
I have another such device myself (not the one I had in mind for you) and love it for comparing all changes I do to the car, as well as logging my track times. Does P600 offer track maps and track logging apart from the straight line accelerations?
Aha :sad: :grin:
Yes track logging!. But the best thing that i was looking for was use the camera and get a overlay on the screen.
:smiley:
Like this, but better quality than this video.. :wink:
https://youtu.be/NcwotOeh_hI
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Aha :sad: :grin:
Yes track logging!. But the best thing that i was looking for was use the camera and get a overlay on the screen.
:smiley:
Like this, but better quality than this video.. :wink:
https://youtu.be/NcwotOeh_hI
I don't see track logging in that video (like your position on the track's map, sectors, lap times etc.) but i guess you could connect it to RaceChrono as an external device anyway.
Any particular reason you want video on the acceleration times? It would be nice but all I'm looking at when people post GPS times is the slope figures!
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Aha :sad: :grin:
Yes track logging!. But the best thing that i was looking for was use the camera and get a overlay on the screen.
:smiley:
Like this, but better quality than this video.. :wink:
https://youtu.be/NcwotOeh_hI
I don't see track logging in that video (like your position on the track's map, sectors, lap times etc.) but i guess you could connect it to RaceChrono as an external device anyway.
Any particular reason you want video on the acceleration times? It would be nice but all I'm looking at when people post GPS times is the slope figures!
I get back when i have tested this device, a review is coming. I have used Racechrone. But think this is the next level...i hope :)
I like to have a video of the accleration times, think it looks more awsome.... :grin:
https://www.instagram.com/p/Bgje2kAFa6O/?taken-by=faceliftgti (https://www.instagram.com/p/Bgje2kAFa6O/?taken-by=faceliftgti)
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I don't understand some of this. Surely the overall diameter (wheel plus tyre) must remain the same for the speedometer to be accurate? The speedometer uses wheel revolutions rather than gps, presumably. So therefore the gearing must remain the same, mustn't it? The only difference I can see is that less rubber means, other things being equal, less deformation and consequently less energy loss. Carrying this to an extreme, if you had solid cart wheels on the car with just a wrapping of a strip of rubber then the friction losses would be minimal even if the ride would be intolerable.
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As I understand it, the weight of the wheel is critical in response. That is, the heavier the wheel, the slower and less responsive the car's handling and performance will feel.
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I can see that if the all up weight i.e. wheel plus tyre is greater then the moment of inertia would be greater and the angular momentum needed to be overcome would be greater thus, as you say, resulting in less responsiveness.
But is it true that a 19 inch wheel plus tyre is generally heavier than an 18 inch plus tyre?
Steel is stronger than rubber for its weight and so I don't see why the above should necessarily be true. Of course the rubber is inflated to give it strength.
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I can see that if the all up weight i.e. wheel plus tyre is greater then the moment of inertia would be greater and the angular momentum needed to be overcome would be greater thus, as you say, resulting in less responsiveness.
But is it true that a 19 inch wheel plus tyre is generally heavier than an 18 inch plus tyre?
Steel is stronger than rubber for its weight and so I don't see why the above should necessarily be true. Of course the rubber is inflated to give it strength.
You'd be surprised how much more material there is in a 19" wheel compared to an 18" one and how little difference in weight there is between an 18" and a 19" tyre of the same rolling radius.
The only thing that bucks the trend is that (sometimes) larger wheels tend to be forged, which for a given size of wheel, tends to be a lighter wheel than a cast one.
I've got 19" BBS SR alloys on mine and they're really quite heavy in comparison to the Austins I took off. Mine are on there primarily for looks - if I were going for performance over anything else I'd have ended up with 18" Team Dynamics Pro Race wheels as they're strong and light.
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Thanks. I understand the bigger wheels feel heavier and the two different sizes of tyres don't feel much different in weight. Do you actually have weights of the wheels and tyres?