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VF2 Brembo Brakes

Pollushon

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DBA 5000 series rotors are 2 piece, but aren't floating rotors.
You should be able to get Brembo overhaul kits, new rotor rings, nuts, bolts and thimbles. Usually around $700 a kit for a pair of kits.

They are totally floaters, that's the whole point of a two piece unless it's some showy knock off that's really a solid. Aluminium 6061 hats with forged steel bolts and cast rings, if you attack them you'll clearly see the movement marks after a track day. Most people will never get any intended use of a floater on the street, not even close
 

Ron Burgundy

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They are totally floaters, that's the whole point of a two piece unless it's some showy knock off that's really a solid. Aluminium 6061 hats with forged steel bolts and cast rings, if you attack them you'll clearly see the movement marks after a track day. Most people will never get any intended use of a floater on the street, not even close

They are not floating rotors...
 

Skylarking

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They are totally floaters, that's the whole point of a two piece unless it's some showy knock off that's really a solid.
The DBA 5000 hats are firmly bolted to the rotor rings using NAS bolts and nuts and their website doesn’t make any mention of fully floating.

https://dba.com.au/products/rotors/5000series/

AIUI, full floating can be identified by the mounting hardware float on the rotor (old style) or the mounting hardware floating on the hat (how the Holden LE & Brembo currently do it).

Having a hat hard mounted to the rotor ring isn’t shonky as the alloy hat saves a fair amount of weigh and aids in reduced heat transfer to the hub which is a benefit in itself. And being solidly mounted it doesn’t chatter which is a benefit to those who spend more time on public roads. But fully floating the DBA doesn’t seem to be else there company has ignored an important feature in its sales blurb….. In any case, someone fitted T3’s rotor rings to their factory Gen6 Camaro hats to retain the fully floating arrangement.

https://www.camaro6.com/forums/showthread.php?t=492428

Such Frankensteining may be possible with out LE brakes? But what benefit is it?
 

Pollushon

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I didn't say fully floating. I said they float, it's via metallurgy but the effect is similar to a supercar rotor although it's nowhere near as pronounced and they don't clink when you shake them. The impact of heat is separated and provides flexibility and independence to the ring in the caliper without compromising the hat/hub. DBA are right not to call them floating because it could be construed misleading whereas brembo are happy to call it floating because their fasteners 'absorb' expansion.... Semantic sure but engineering is engineering, there are varying degrees of float, the best examples of which are bikes and motorbikes
 

RevNev

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they float, it's via metallurgy but the effect is similar to a supercar rotor although it's nowhere near as pronounced and they don't clink when you shake them.
The purpose of a floating race rotor is to minimise pad knock off from upright flex and/or hub bearing clearance causing the rotor to move forcefully within the caliper against the pads and pushing the pistons back into the calipers. Next brake application in knock off, is a long pedal or worst case scenario, the pedal hits the floor with no brakes requiring the driver to pump the pedal in the next brake application. You often see race car brake lights flash halfway down the straight and the driver will be doing a quick left foot brake pump to get the pedal back up before the next corner from pad knock off in the last corner. Pad knock off is virtually eliminated with sliding OEM type calipers as the caliper can float with the rotor in a flex situation.

Commodore's VR onwards are bad for pad knock off with 4 and 6 spot calipers and big rotors from hub bearing clearance and usually require anti knock off springs behind the caliper pistons if full floater rotors aren't permitted in a racing category or aren't used for cost containment. Harrop used to do a tapered roller bearing hub conversion to remedy hub induced rotor flex and pad knock off on their race brake setups.

A metallurgic float is useless for that application and is the reason Supercar rotors physically wobble around on their hats. I saw a bloke fix the float once, he thought the bolts had stretched and the rotor was about to depart from the hat!
 
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panhead

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The purpose of a floating race rotor is to minimise pad knock off from upright flex and/or hub bearing clearance causing the rotor to move forcefully within the caliper against the pads and pushing the pistons back into the calipers. Next brake application in knock off, is a long pedal or worst case scenario, the pedal hits the floor with no brakes requiring the driver to pump the pedal in the next brake application. You often see race car brake lights flash halfway down the straight and the driver will be doing a quick left foot brake pump to get the pedal back up before the next corner from pad knock off in the last corner. Pad knock off is virtually eliminated with sliding OEM type calipers as the caliper can float with the rotor in a flex situation.

Commodore's VR onwards are bad for pad knock off with 4 and 6 spot calipers and big rotors from hub bearing clearance and usually require anti knock off springs behind the caliper pistons if full floater rotors aren't permitted in a racing category or aren't used for cost containment. Harrop used to do a tapered roller bearing hub conversion to remedy hub induced rotor flex and pad knock off on their race brake setups.

A metallurgic float is useless for that application and is the reason Supercar rotors physically wobble around on their hats. I saw a bloke fix the float once, he thought the bolts had stretched and the rotor was about to depart from the hat!

I 'Liked' this post because I was dazzled by the science.







.
 

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I didn't say fully floating. I said they float…
Fair enough…. When I hear float I understand fully floating :p
…it's via metallurgy but the effect is similar to a supercar rotor although it's nowhere near as pronounced and they don't clink when you shake them.
I’ve never heard the term metallurgic float and don’t really know what that means…

For me, installing race brakes is not my day job, but AIUI the rotor is either bolted tight to the hat and can’t move or it’s bolted tight but with other hardware in between the ring and hat (like stainless drive bobbins in slots that allow movement movement between the ring and hat or similar hardware).

And I always understood the purpose of fully floating discs was primarily to cater for expansion of the ring so as to reduce rotor stresses and thus rotor cracking under severe application.

I’ve also heard of pad knock back but if fully floating rings resolved such issues then supercar drivers wouldn’t do pre corner brake touches. So I’m not convinced about that but I’ll defer to those members that play on tracks :cool:

Whatever the case, such brakes are overkill on public roads. Only in NT can one drive at 130kph? max while other parts of Aus we are limited to 100 or 110 max :confused: Such slow speeds are hardly enough to see rotors explode due to heat stresses as was seen in supercar racing :p And if your caught by Police going in hard at every corner, you might find a “driving without due care” or “dangerous driving” charge on thecards. Really, sensible driving on public roads should never see us get close to the capability of fully floating rotors to justify them on performance :( The police are confident in the bigger police pack rotor and single cylinder mondo caliper and they punish their cars on the road. But me, I like the Brembo and floating rotor look so I justify them on such a vanity basis… yes vanity drives us all :p:p:p
 
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