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Post by duratec1999cc on Apr 15, 2015 0:07:47 GMT
I weighed my standard 15 inch ford wheels at 14.4Kg with tyre, if i spent about £800 on some 15 inch OZ ultraleggera wheels i could reduce this by 0.8Kg per wheel, so for my current build budget its not worth it, maybe a future upgrade though.
To counter the effect of the extra rotational mass of 17 inch wheels, a whole boat load of weight loss would need to be achieved in other places.
Supposedly, losing 1Kg of rotational mass is equivalent to losing 10Kg off the chassis, and even then, you wont recover the important loss in unsprung to sprung weight ratio.
I understand from your initial posts that budget is not an issue, so if it were myself I would spend the bottomless budget reducing as much unsprung weight as possible (carbon ceramic discs, F1 style carbon wishbones etc.) and also any sprung weight where i could while still retaining a sensible weight distribution. There would be no point having a car that is as light as it can be but the weight distribution is all wrong and it ends up handling badly.
Oh, and i would spend some of the budget on a fleet of supercars too... :-)
Is time an issue? If time was not an issue then i would spend the time designing and achieving the same as above.
However if time or money had a limit (which surely it must) i would spend most of it (up to the point of diminishing returns) reducing the unsprung weight, then whatever i have left i would spend on reducing the sprung weight.
Thats just my opinion, expressing what i would do.
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Post by sammy on Apr 19, 2015 16:37:25 GMT
In fact we are making a prototype(Cycle wings)
But as I said before we are not sure that will work. And carbon ceramic disch a good idea.Where you can buy? As for f1style carbon wishbone: to build similar pieces must also know the carbon thickness and the correct geometry.
Are things that really knows an engineer f1.
I do not know anybody who can do that.
Or do not have to do road tests with the risk of skin. if you were in my car for example Cycle wings break and dangerous, but never so dangerous carbon wishbone if you should break up. Nom must not forget that my car will have to be driven in a country that is not England.For example of 10 cars with gsx-r throttle body is only one of the possibilities this acceptet.
For metal i have pc simulations to test their functionality and strenght.
No with carbon.
Anyway if anyone knows a capable engineer in the field of carbon kindly let me have a contact.
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Post by kiwicanfly on Apr 19, 2015 19:57:15 GMT
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Post by casesensitive on Apr 19, 2015 21:12:56 GMT
I weighed my standard 15 inch ford wheels at 14.4Kg with tyre, if i spent about £800 on some 15 inch OZ ultraleggera wheels i could reduce this by 0.8Kg per wheel, so for my current build budget its not worth it, maybe a future upgrade though. My 17s were 18.9kg each, my Puma (offset 34) F1-style with Toyo T1Rs were 14.8kg, which is disappointingly heavy, but still a 20kg unsprung saving, definitely worth it. |
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Post by kiwicanfly on Apr 20, 2015 0:42:40 GMT
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Post by duratec1999cc on Apr 20, 2015 22:41:56 GMT
Reckon that if you now fit normal rotors Sammy you will be letting us all down  While fitting some new front upper wishbones that I got back from the powder coaters, I took the opportunity to weigh parts of the front suspension setup. the heaviest single component at the front is the focus rear stub axle/bearing/hub assembly at 4.2kg second heaviest is the solid/unvented brake disc at 3.8kg (imagine how much more a vented disc will weigh too) third heaviest is the rtr steel upright at 1.8kg then the caliper mounting bracket at 1kg (this is way over engineered, an alloy replacement, or a thinner titanium on would be better) Caliper is feather weight at 800g, seems a bit daft that the bracket is heavier than the caliper! ill post the full list in a technical thread soon, wishbones are quite light, but the weight affect is not as simple as the stuff at the end near the wheel. i reckon a carbon ceramic disc will weight less than half of the iron disc. are you using the rtr uprights or the rally design ones? Anyone know the weight of the rd uprights complete with bearing and hub? |
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Post by kiwicanfly on Apr 21, 2015 0:13:49 GMT
I have also found differing opinions on the suitability of titanium as a rotor. I turns out that it does not dissipate the heat well so the heat has to go somewhere else, in some cases into the caliper melting that instead  |
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Post by casesensitive on Apr 21, 2015 8:48:44 GMT
With all this talk of boiling brake fluid, why has no one (that I've heard of) done a liquid-cooled brake line? When pads heat up, they heat the piston which in turn heats the fluid, which alters its properties. I've seen bodywork that scoops air onto the brake setup, but never anything liquid. Obviously not an option for the discs.
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Post by Paul (madeye) on Apr 21, 2015 11:26:31 GMT
although the ceramics are light, im not convinced they will actually stop you Sammy on a road car. you will never get enough heat in.
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Post by mawdo81 on Apr 21, 2015 11:44:49 GMT
The fluid is static so youd need to circulate the additional cooling fluid which would add weight and complexity. Controlling the disc temp would and is more efficient and effective.
Sent from my GT-I8190N using proboards
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Post by mawdo81 on Apr 21, 2015 11:47:35 GMT
A few years back Ferrari in f1 engineered their wheels to force air through the brake set up and then used the air for downforce but it was banned as it was deemed a moveable aerodynamic device.
Sent from my GT-I8190N using proboards
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Post by sammy on Apr 22, 2015 7:15:11 GMT
although the ceramics are light, im not convinced they will actually stop you Sammy on a road car. you will never get enough heat in. And also the fact that until now I could read in the internet. Can not maintain the right temperature when you're not on track. So even if you save something in weight, braking will not be the best. |
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Post by sammy on Apr 23, 2015 7:15:32 GMT
Here I have a couple of information that may be of interest. I weighed some tires and rims. tires: yokohama advan Neova AD08 195/50/15 Declared weight from Yokohama: ca. 7KG Actual weight measured: 7,7KG Weight rims and tires ATS DTC 7,5X17 ET40 -Hankook Ventus 205/45/17 Ages: 16,3-16,1KG  Total weight rims and tires 15: ca.12,5kg  |
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Post by duratec1999cc on Apr 23, 2015 22:35:02 GMT
Those 15" rims must be really light, what are they?
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Post by duratec1999cc on Apr 23, 2015 22:43:05 GMT
although the ceramics are light, im not convinced they will actually stop you Sammy on a road car. you will never get enough heat in. And also the fact that until now I could read in the internet. Can not maintain the right temperature when you're not on track. So even if you save something in weight, braking will not be the best. There are lots of high performance road cars that use these kind of discs, and most of those cars are not designed exclusively for track use. They must be able to stop those cars well enough in normal road driving (which is what most of them will be used for anyway) otherwise the manufacturers would not be able to them. |
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