Floating discs, rattly question GT3 mk1
Discussion
I've got the alcon/brembo (cant remember which) floating discs on my Mk1 GT3 done by Parr last year.
I dont mind the noise but want to check what i'm getting is normal.
On driving the car and say coasting to a stop, you hear the rattling. I would expect the rattling to stop the moment i step on the brake pedal, but the rattling seems to get louder if i brake. Does that sound normal?
cheers
Ajit.
I dont mind the noise but want to check what i'm getting is normal.
On driving the car and say coasting to a stop, you hear the rattling. I would expect the rattling to stop the moment i step on the brake pedal, but the rattling seems to get louder if i brake. Does that sound normal?
cheers
Ajit.
Yup - thats normal 
The cars sound like traction engines at low speed with these discs on. The only thing you can do to quieten them down a 'little' is to buy a set of anti-rattle shims for the back of your pads (if you don't have them already).
You will find that they do go quiet when used on track, and will stay like that for about 50 miles until the rattles return. You won't look back with the conversion though because they won't crack.
Parr discs are Brembos BTW.
Cheers
Steve M
The cars sound like traction engines at low speed with these discs on. The only thing you can do to quieten them down a 'little' is to buy a set of anti-rattle shims for the back of your pads (if you don't have them already).
You will find that they do go quiet when used on track, and will stay like that for about 50 miles until the rattles return. You won't look back with the conversion though because they won't crack.
Parr discs are Brembos BTW.
Cheers
Steve M
Edited by Merritt on Sunday 21st January 15:48
polarexpress said:
fyi, the generation 2 floating Alcons (JZM) don't rattle at all, regardless of miles.
Why do the Brembo discs rattle after 50 miles? Surely should be an easy problem to fix if the shims were designed accordingly?
Why do the Brembo discs rattle after 50 miles? Surely should be an easy problem to fix if the shims were designed accordingly?
Because after expanding due to the heat on track they have cooled down a bit and thus start to rattleb again.
Keep em hot!
996tt_stevo said:
Should just do steels, yip! I know they crack eventually and the Alcons/Brembos last 2/3 times as long, but the steels price is very low now, I'm picking up at £160 a disk, the 2nd generation Alcon is pretty good!
Stevo, care to tell us where you can get 350 mm steelies from at that price? can you get front AND rears at discount prices ?
Edited by slippydiff on Sunday 21st January 17:27
slippydiff said:
996tt_stevo said:
Should just do steels, yip! I know they crack eventually and the Alcons/Brembos last 2/3 times as long, but the steels price is very low now, I'm picking up at £160 a disk, the 2nd generation Alcon is pretty good!
Stevo, care to tell us where you can get 350 mm steelies from at that price? can you get front AND rears at discount prices ?
Edited by slippydiff on Sunday 21st January 17:27
lol, I will confirm with you in PM later as there are ongoing issues regarding offset of discs, you will love this!
996tt_stevo said:
slippydiff said:
996tt_stevo said:
Should just do steels, yip! I know they crack eventually and the Alcons/Brembos last 2/3 times as long, but the steels price is very low now, I'm picking up at £160 a disk, the 2nd generation Alcon is pretty good!
Stevo, care to tell us where you can get 350 mm steelies from at that price? can you get front AND rears at discount prices ?
Edited by slippydiff on Sunday 21st January 17:27
lol, I will confirm with you in PM later as there are ongoing issues regarding offset of discs, you will love this!
Stevo copy me in please mate,i'm back to 350mm GT3 cups, the floaters lasted ages but the noise.....
Cheers
Rob
gfreeman said:
polarexpress said:
fyi, the generation 2 floating Alcons (JZM) don't rattle at all, regardless of miles.
Why do the Brembo discs rattle after 50 miles? Surely should be an easy problem to fix if the shims were designed accordingly?
Why do the Brembo discs rattle after 50 miles? Surely should be an easy problem to fix if the shims were designed accordingly?
Because after expanding due to the heat on track they have cooled down a bit and thus start to rattleb again.
Keep em hot!
If there are anti-rattle shims as Steve suggests with the Brembos, they should remain anti-rattle after 50 miles...
polarexpress said:
gfreeman said:
polarexpress said:
fyi, the generation 2 floating Alcons (JZM) don't rattle at all, regardless of miles.
Why do the Brembo discs rattle after 50 miles? Surely should be an easy problem to fix if the shims were designed accordingly?
Why do the Brembo discs rattle after 50 miles? Surely should be an easy problem to fix if the shims were designed accordingly?
Because after expanding due to the heat on track they have cooled down a bit and thus start to rattleb again.
Keep em hot!
If there are anti-rattle shims as Steve suggests with the Brembos, they should remain anti-rattle after 50 miles...
Steve at JZM said the Brembos are race discs/bells and thus Brembo made no effort to make them "street useable"
996tt_stevo said:
Should just do steels, yip! I know they crack eventually and the Alcons/Brembos last 2/3 times as long, but the steels price is very low now, I'm picking up at £160 a disk, the 2nd generation Alcon is pretty good!
Come on Steve tell all! I'm sure there are a number of us on here that would be interested....
I can get fronts (Mk1) for £145+vat and rears for £97 + vat but the MK2's are £290+vat for the fronts
polarexpress said:
If there are anti-rattle shims as Steve suggests with the Brembos, they should remain anti-rattle after 50 miles...
Adrien -
The Brembo setup has a number of 'rattle' sources. The most obvious is that the bell and disc deliberately have a lot of play between them when cold. You can hear the disc moving around on the bell at low speed and there isn't a lot you can do about it. This rattling is however exacerbated if there are no anti rattle shims between the piston calipers and the pads (because the pads then rattle against the pistons). The shims are often removed because they: (a) are very expensive for what they are (b) make it a P.I.T.A to change pads quickly (c) don't fit in some cases if you have replaced OEM pads with aftermarket ones such as RS29s. I tend to put new pads on the car without the shims, do a trackday or two then put the shims back in because it makes a reasonable difference on the road.
Its not a problem for me either way because I always take the wheels off for brake / disc / pad etc inspection after a track day.
Steve
Edited by Merritt on Monday 22 January 08:19
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