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Author Topic: The balancing act of wheel, brake and tyre sizes  (Read 3996 times)

Offline CalMac

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The balancing act of wheel, brake and tyre sizes
« on: June 17, 2021, 11:42:07 am »
Hi all, I know wheels have been done to death. I think my Q is a little different.

What do you guys reckon in the ‘best’ wheel size / brake size / tyre size combo to get the most out of your gti?

I see a lot of people run 17s on track because of the cheaper tyres, but also as I believe they would have generally a lighter brake setup, and perhaps better acceleration than an 18” wheel as there is more sidewall to squash into the tarmac. I’ve read many people complaining of brake fade and moving from 17s up to 18s to fit a bigger brake setup.

18” wheels have the advantage of better steering response because of a shorter sidewall and you are able to run bigger brakes at the cost of more weight.

What do you guys consider to be the best? I’m steering towards 17” being the most preferable option here. Please let me know if I’m chatting b*llocks, I would like to hear anything you guys have to say on this  :smiley:

Decent video on wheel sizes:

https://m.youtube.com/watch?v=mPyg3ilw3KU

Offline Clarkj93

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Re: The balancing act of wheel, brake and tyre sizes
« Reply #1 on: June 17, 2021, 12:30:19 pm »
For me... given the option I would go for 17's as they will be slightly lighter. My understanding is the NQSBBK and r32 calipers fit under 17's which should be enough.

The ProductionGTI series run r32 or gti calipers with ferrodo DS2500 pads (from memory), semi slicks, stripped interiors and usually brake ducting. This seems to be enough for them to run races along the 20 min mark.

Personally I am on the stock gti caliper and plan to continue so for now, I've had brake fade issues so just added some additional ducting, removed the dust shields, bought some much more tolerant brake pads, better fluid and will be removing somewhere between 60-100kg of weight for track work. This should be enough but its all trial and error! This will be paired with some Nankang ns2r's also.

In terms of wheel size I would always just get the smallest (and lightest) wheel I can fit over the brakes personally and would not really pay attention to other aspects.



Offline CalMac

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Re: The balancing act of wheel, brake and tyre sizes
« Reply #2 on: June 17, 2021, 12:41:17 pm »
Thanks this is a really useful for me, I’ve been eyeing up some 17x8 alleggeritas.

It’s always a learning curve and I appreciate this help!

I’ll check out your build thread, sounds like my kind of thing.

Offline bobby_fodge

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Re: The balancing act of wheel, brake and tyre sizes
« Reply #3 on: June 17, 2021, 01:36:57 pm »
I have the NQSBBK fitted and run 18's, only because 18's came on the car when I bought it.

I have 225/40 tyres on them. I bought the 40 profile tyres to give me a bit of cushioning but then polybushed the car.

I have kept the standard front disc size rather than fit the larger Merc discs. As my car is only used on the road I thought i would save the extra weight of the Merc discs and I wouldn't be needing the extra cooling of the larger discs that I guess would be needed on a track.

I do plan on fitting cooling ducts though.


Offline CalMac

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Re: The balancing act of wheel, brake and tyre sizes
« Reply #4 on: June 17, 2021, 02:17:24 pm »
I have the NQSBBK fitted and run 18's, only because 18's came on the car when I bought it.

I have 225/40 tyres on them. I bought the 40 profile tyres to give me a bit of cushioning but then polybushed the car.

I have kept the standard front disc size rather than fit the larger Merc discs. As my car is only used on the road I thought i would save the extra weight of the Merc discs and I wouldn't be needing the extra cooling of the larger discs that I guess would be needed on a track.

I do plan on fitting cooling ducts though.



I see, that makes sense for your situation. How are the 18s working for you, are you going to to stick with them or do you plan on changing?

I am in a similar position, currently a road car but would take it on track in future with more knowledge and a better prepared car.

my car is bone stock and am going to be doing wheels tyres suspension and brakes before power mods, the NQSBBK would be my primary option for a caliper upgrade should I choose to stay 17”, 18” would allow me to fit the ml350 discs and cayenne 18z calipers.

Stock brakes for me are sufficient for 99% of road use so I’m not in a rush to change them but I’ve still gotten them very hot on multiple occasions and I don’t feel I can get the best out of my car with them. I wish our cars allowed left foot braking I miss using that.

Ultimately it boils down to how much I am willing to spend and as nice as a 2 piece brake disc setup is, £2000 is a bit much for me. I have more research to do on this though.
« Last Edit: June 19, 2021, 01:28:57 am by CalMac »