Scottish Borders
Strange I’ve got drilled discs on all 3 cars front / rear .never seen an issue..is it pad related ?
Help finding drilled rear discs
- Thread starter RMB
- Start date
Dunno, I had MTEC dimpled and grooved disks and with their pads on the front of mine. Very noisy.
At the summit of the picturesque fens
If you go drilling multiple holes in a solid lump of steel and get it hot, then cold, then hot ad infinitum, it's hardly surprising they are prone to cracking.
absolutely, it better to buy discs with the holes cast into them
They're not cast, they are drilled. Then they are countersunk to avoid any sharp edges and to give somewhere for the brake dust to collect. So by countersinking they are even less structurally sound.
I honestly thought that only the 'max power' brigade of kids were interested in drilled discs these days, not grown-ups with sense.
AFAIK it’s only Porsche that have cast hole discs?
My crusty old drilled rear discs are ancient.
More rust than braking surface, zero cracks or anything bad.
My fronts are the (1k miles old) Z4M drilled, they're also fine.
I've had both expensive drilled and cheap drilled over (many) years and numerous cars and never had any issue.
I know folk who've been using cheap drilled for years and years, also drive their higher performance cars much harder than I do, again, no issues.
Not saying drilled discs don't crack, but I've never seen or heard of it personally.
More rust than braking surface, zero cracks or anything bad.
My fronts are the (1k miles old) Z4M drilled, they're also fine.
I've had both expensive drilled and cheap drilled over (many) years and numerous cars and never had any issue.
I know folk who've been using cheap drilled for years and years, also drive their higher performance cars much harder than I do, again, no issues.
Not saying drilled discs don't crack, but I've never seen or heard of it personally.
My AP drilled discs on my Corrado VR6 never cracked (lots of trackdays too), my BMW/ATE drilled discs on the Z4MC haven't either (lots of trackdays / Ring trips)...but on the other hand the BMW/SHW plain discs on my e34 M5s never warped or cracked either.
I suppose quality matters!
I suppose quality matters!
There are two versions of the material for discs.. normal ones are just cast and machined ..some folks offer 'high carbon' content discs which are supposed to be tougher..I assume also more crack resistant..FWIW I've always fitted drilled discs..only one that cracked was a Zimmerman on the 35is where my local garage muppet had badly installed the pads putting ahuge side load on one one side..
From my experience, it's best to keep an eye on them and check the inside, not just the outside for cracks.
I've posted a picture of both of my rear discs cracked in this thread mate, so there's evidence it can happen right there. Fronts were also cracking, so it's defo a thing and can happen. The higher quality the disc/manufacturing process, the less chance I suppose. But MTec are cheap for a reason, and they aren't a quality product, unfortunately.
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Up to you mate, I'm not saying they defo will or defo won't. I'm more saying i won't buy cheap discs again and regularly check for cracking if I bought drilled.
I now run totally plain discs high carbon on track without any issues. Drilled, grooved, etc, are more for looks than anything else anyway, unless you are seriously tracking the car and wanting to do long stints on track. Then, grooved are probably worthwhile.
I now run totally plain discs high carbon on track without any issues. Drilled, grooved, etc, are more for looks than anything else anyway, unless you are seriously tracking the car and wanting to do long stints on track. Then, grooved are probably worthwhile.
Z44Jon
Member
That looks great but the tyre wall repair and tyre manufacture date would worry me.