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D2 - Axles, Brakes, Suspension and Steering Brakes, Springs, shocks, steering racks, steering columns, suspension arms, wheel hubs etc.

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  #21  
Old 2nd October 2020, 05:06 AM
spannerrash spannerrash is offline
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Did anything ever pan out for the brake block? Am interested in buying one if I can find one.
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  #22  
Old 2nd October 2020, 09:13 AM
MikkiJayne MikkiJayne is offline
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I stopped development of the 3d printed one as the brakes on my S8 are so terrible anyway it makes no measurable difference. I may have another look at it over the winter when mine comes in for some updates. I have found a local company who do short-run CNC work so if I can print a working prototype there is an option to get a batch made in aluminium.
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  #23  
Old 2nd October 2020, 04:01 PM
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The_Laird The_Laird is offline
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Why are the S8 brakes so poor? My car has new or refurbished calipers, decent discs and newish pads. They have been pressure bled a number of times. But they still feel soft and unconvincing. Are there any pads or disc & pad combinations that might improve this?
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  #24  
Old 2nd October 2020, 04:17 PM
MikkiJayne MikkiJayne is offline
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There are three problems I think.

#1 is that the calipers are just a poor design and introduce a lot of friction between the caliper and the pad, which then needs more pedal pressure to generate a decent amount of friction between pad and disc. Big Red's brakes (standard 2-piston sliding calipers) are better than any of my S8s.

The solution to this is different calipers. B7 RS4 calipers work well, but are excessively expensive, as are the discs. Aftermarket calipers can also work well, but again can be very expensive. Tbh there's not really a cheap solution to this which I have found yet, although I keep looking.

#2 is the ESP return pump which is fiendishly difficult to bleed properly and so makes it likely there is air in the system despite best efforts to the contrary.

The only solution to this is to never let the system run dry, and to change the brake fluid regularly.

#3 is the flexible bulkhead which is the root of this thread. Some of the pedal effort goes in to moving the sheet metal rather than pushing hydraulic fluid to the calipers, which reduces efficiency and pedal feel. My A6 has better brakes than any stock D2 because the pedal cluster is totally solid.

Some kind of bracing is in order, hence the block between the master cylinder and the strut brace
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  #25  
Old 2nd October 2020, 08:31 PM
spannerrash spannerrash is offline
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Every little helps so if you or anyone persues this I'd like one please.

If anyone has a template / drawing I'd be happy to talk to some local engineering firms, see if they can help at all.
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  #26  
Old 5th October 2020, 12:39 AM
GH77 GH77 is offline
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Count me in for a brake block too, please!

My D2 brakes are always kept in good order but definitely feel a bit off after driving the D3 during the week.
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  #27  
Old 20th October 2020, 05:19 PM
Markiii Markiii is offline
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friend has just 3d printed me one which I'm trialling at the moment

trying to talk him into a batch what do people think is a good price?
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  #28  
Old 20th October 2020, 05:42 PM
MikkiJayne MikkiJayne is offline
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Have you noticed an improvement? What is it printed from?
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  #29  
Old 21st October 2020, 03:53 AM
spannerrash spannerrash is offline
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Well done for taking this up but we would need more details before we can even think of putting a price on something. Its probably better if you and your friend decide the price based on your costs etc. No point in us just throwing out random numbers.

Keep us informed as to how you testing goes.

Cheers Frank
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  #30  
Old 21st October 2020, 07:58 PM
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Stromaluski Stromaluski is offline
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Quote:
Originally Posted by MikkiJayne View Post
The solution to this is different calipers. B7 RS4 calipers work well, but are excessively expensive, as are the discs. Aftermarket calipers can also work well, but again can be very expensive. Tbh there's not really a cheap solution to this which I have found yet, although I keep looking.
Is changing to D2 A8 spindles and using D3 A8 calipers/rotors not an easy solution over on your side of the pond?
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