Tuscan discs on a Cerb
Tuscan discs on a Cerb
Author
Discussion

sethlj

Original Poster:

367 posts

277 months

Wednesday 14th April 2004
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My 4.5 has been fitted with drilled Tuscan disc by a main dealer. Now that they are well and truely bedded-in there is still a very noticable high frequency vibration from them when braking at speed (70ish).

The vibration is not a warped disc (as I have had one of them before) but feels more like the drilled holes being uneven on the disc. The dealer has told me 'this is the norm and will fade over time' but as I had the discs replaced because of a warp judder it seems that I have replaced a low frequncy vibration with a high one.

Is this right or should drilled discs be as smooth as an undrilled discs? I have had drilled discs before on an Evo VI and these were as smooth as silk even under heavy, high speed braking.

Your thoughts?

S.

J_S_G

6,177 posts

272 months

Wednesday 14th April 2004
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sethlj said:
The vibration is not a warped disc (as I have had one of them before) but feels more like the drilled holes being uneven on the disc. The dealer has told me 'this is the norm and will fade over time' but as I had the discs replaced because of a warp judder it seems that I have replaced a low frequncy vibration with a high one.

Is this right or should drilled discs be as smooth as an undrilled discs? I have had drilled discs before on an Evo VI and these were as smooth as silk even under heavy, high speed braking.

Thoughts...

1. This is opening up the whole warped disc urban legend again!
2. I've actually got a couple of Cerb 4.5 discs on my Tuscan. Joolz, didn't you once mention that Tuscan discs shatter easier?

joospeed

4,473 posts

300 months

Thursday 15th April 2004
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They crack across the drillings if you give them some staick on road or track. they're cheap and cheeful (for TVR discs) but ultimately not great for a performance car

j_s_g

6,177 posts

272 months

Thursday 15th April 2004
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joospeed said:
They crack across the drillings if you give them some staick on road or track. they're cheap and cheeful (for TVR discs) but ultimately not great for a performance car

Joolz, a certain cheque's turned up in the post today.

I'll drop it off for you when I bring the car in for the Nitrons, if that's ok with you? (And make sure you've got plenty of free time for looking at the other niggles, eh? )

joospeed

4,473 posts

300 months

Thursday 15th April 2004
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yeah, I'm sure I can help you spend that

washy

950 posts

298 months

Thursday 15th April 2004
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Seth - I had this problem on my 2003 4.5 and it didn't go away. I actually ended up sourcing the earlier 4.5 mounting bells (do you still have these or can you get them?), fitting 330mm AP racing discs and changing the pad compound. Brakes are now awesome with zero judder.

What pads are you using? Try a pad that doesn't transfer a huge amount of material to the disc. I've gone for carbon metallic pads for this very reason (not to mention the huge temperature range and near linear performance throughout).

Washy