Unblocked my drilled discs today

Guest · Mar 26, 2005

I unblocked the holes in my discs today (for info I believe there are 144 per disc).
On my previous car, C4S, I thought I used a 4mm drill bit, but today I needed to use a 3.5mm drill bit.
You just poke it through both inner and outer disc, using finger pressure.
I had 5 holes on the offside rear, and 6 on the nearside rear where I could not push the bit through the inner disc.
I didn't have any problems on the previous car.

It might be psychological, but it seemed to be braking better on a drive this afternoon.

I also felt the inside of the front and rear discs. Due to the dust covers, you can only feel a portion of them, but they feel nice and smooth - not pitting. So they have survived the winter.

I had a look under the rear as well.
The exhaust system is not stainless, at least not by the surface rust that is forming. It's not rusting at a quik-fit exhaust pace, so it'll last more than 13 months, but I'll see how many years I get out of it.

I also nourished the leather, to protect it a bit now the sun and UV's are going to start appearing. Having a leather interior is nice, but you notice how much there is if you have to clean/feed it all.

sailor · Mar 27, 2005

Stuart
Re the blocked disc holes, I had the same thing done about 3 years ago by my OPC, at the last service I asked them to do, before switching to an independent.My beast is inclined to spend periods of 4 to 6 winter weeks in the garage and, despite the garage being reasonably dry, I found that the brakes would rust up, requiring a bootful of reverse power to break them free. The resultant bang would panic milady who feared some sort of an attack.
After the last episode of this, I had heavy juddering despite deliberate heavy braking to try to clean the discs up. At my last service I had the discs skimmed, plus new pads (which were needed anyway), and this improved the feel no end. My independent confirmed that he had the same problems until he put a dehumidifier in his garage - end of problem apparently.
I did some research on the rusty brake phenomenon, since my other hotrod, a tuned Peugeot 205 GTI, does not suffer the same way. It seems that from the 993 series, the factory had the chromium content of the disc steel removed, because of persistent customer complaints of "squeaky brakes"! This may be the answer.

JohnC
993TT 430

Sundeep · Mar 27, 2005

interesting that after the recent bedford day all of the drilled holes on my discs are now block with brake dust and I was going to do this in the next few days !

rears only as the front discs & pads have had enough (pads down to min & discs have mini cracks all over them!) may try for 993 turbo callipers but not sure how much a set are !??

Elliot Davies · Mar 27, 2005

I unblocked mine on the S with a plastic headed nail (the type used for upvc facias etc.) which has grippers so clears out the holes easily with a tap on the nail.
Same diameter too [

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vic cohen · Mar 27, 2005

For future ref if u run track days with worn pads , like starting with much less than 50%, the heat dissipation is poor leading to cracked discs very quickly