Increased rolling diameter and braking efficiency

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Increased rolling diameter and braking efficiency

Post by bjk »

Just looking for some anecdotal information (as I doubt I'll get much else :lol: ) on whether people who've increased the overall rolling diameter via larger wheels/tyres, noticed a decrease in braking efficiency? I certainly don't think I did, though maybe if there was any it was mitigated by the decent pads and marginally greater contact patch. I can sort of see how this could be the case, without really knowing the science, and it's the DPTI's line in any case.

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Re: Increased rolling diameter and braking efficiency

Post by vipfto »

Will cause less braking less torque and less fuel economy and mess gears a little

Will be hardly noticable depending on what else is done to car to offset it
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Re: Increased rolling diameter and braking efficiency

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vipfto wrote:Will cause less braking less torque and less fuel economy and mess gears a little

Will be hardly noticable depending on what else is done to car to offset it
What sort of percentage out do you think it would have to be before it is detrimental/noticeable? I mean sure, admittedly there needs to be some legislation to stop people throwing 21" inch wheels on their Mirages, but while I was at Regency I had to pass their rolling brake test, and if there was no problem there, and it clears the body work (hopefully more so now with the 225's lol), surely that's evidence enough that it's within reason I suppose?
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Re: Increased rolling diameter and braking efficiency

Post by Technikhaus »

I found my braking performance was increased, as I could hit the pedal harder and it wouldn't lock up as quickly...
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Re: Increased rolling diameter and braking efficiency

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That will usually be the case as wider footprint with larger tyres. But its not always the case if staying same width but taller tyre will take longer to stop
The percentage works out to be exactly 2.567fuckedifiknow% You will need some formula to work that out
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Re: Increased rolling diameter and braking efficiency

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Very precise, sir!
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Re: Increased rolling diameter and braking efficiency

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You're getting waaaay too sciencey and mathsey for us simple mechanic folk...
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Re: Increased rolling diameter and braking efficiency

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Blame the government haha.
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Re: Increased rolling diameter and braking efficiency

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I didn't read past "anecdotal" as that word pissed my brain off lol
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Re: Increased rolling diameter and braking efficiency

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Sahin wrote:I didn't read past "anecdotal" as that word pissed my brain off lol
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Re: Increased rolling diameter and braking efficiency

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TL;DR

Got big tyres? How's ya braking?
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Re: Increased rolling diameter and braking efficiency

Post by Sahin »

I'm running 235/45 and my braking is better due to the footprint and me being able to just full brake with no loss of traction
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Re: Increased rolling diameter and braking efficiency

Post by SchumieFan »

It will be negligible.

The road surface will have more of an impact.

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Re: Increased rolling diameter and braking efficiency

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Cheers guise.
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Re: Increased rolling diameter and braking efficiency

Post by Daniel2019 »

Nope, we tested it around a roundabout next to a park full of kids playing soccer.

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Re: Increased rolling diameter and braking efficiency

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I feel there are better ways to test these things. :lol:
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Re: Increased rolling diameter and braking efficiency

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Maybe if it was in a school zone or something is the only way to improve that test :lol:

Tested in real life scenario, what could be better? We're all about safety here at Martin Motorsport.
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Re: Increased rolling diameter and braking efficiency

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Martin Motorsport wrote:Keeping risk safe.
:hmm:
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Re: Increased rolling diameter and braking efficiency

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Precisely!
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Re: Increased rolling diameter and braking efficiency

Post by Bennoz »

Sounds like you need Brembos. And a turbo.
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