the more funky the pattern, the cooler you look

grooves skim the pad lightly so your meant to have a fresh pad surface whenever you brake (no pad glazing) im guessing straight or angled grooves and and how many determine how much the skim off per rotation is.

holes help disapate heat, however i hear that sometimes when your discs overheat, these holes cause so much of a tempreture difference they cause excess contraction in relation the rest of the disc that sometimes they can cause cracks and fracture the disc.

i figure this bad effect with drilled holes is increased further by a vented disc, as the vents sort of work like little turbines pushing air out the hole and further cooling that localised area.

id go with curved or straight grooved with no holes personaly, if you go with curved grooved make sure you fit them the the correct way round.

keep the vents in em clean once in a while with a long thing wire brush in a drill.

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the world is changed by people in sheds

Well I've just bought some new rotors with a straight groove now

I was advised not to buy x-drilled, as they have a tendency to crack

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FRESHLY RE-FURBISHED GTI BEAMS
FITTING AND LOWERING AVAILABLE.
ALL AXLES BUILT USING GENUINE PEUGEOT PARTS

IF I'M NOT HERE, IT ONLY MEANS ONE THING.... I'M SOMEWHERE ELSE!

I just replaced the old units with exactly the same spec in the end.

I just used a slightly bigger rotor

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FRESHLY RE-FURBISHED GTI BEAMS
FITTING AND LOWERING AVAILABLE.
ALL AXLES BUILT USING GENUINE PEUGEOT PARTS

IF I'M NOT HERE, IT ONLY MEANS ONE THING.... I'M SOMEWHERE ELSE!

Std. discs and good pads are more than adequate for road use.

Yes, grooves do very lightly skim the pads to remove any brake glazing, but under road use your pads simply will not get hot enough to glaze over. The glaze is the adhesive component in the pad material melting, rising to the surface and hardening again when it reaches cool air. For this to happen the material of the pad has to be heated up to very large temperatures under prolonged abuse.

You're probably just increasing wear on the pads, at increased cost, with little tangible benefit fitting grooved discs to a road car that doesn't brake hard repeatedly.

Likewise with drilled discs, did your old brake discs melt or warp under extreme heat? If no, then I also see very little point in bothering with them.

By all means if you take the car on track and want to combat the negative effects of the brakes getting too hot then they are worth looking at.

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61k miles Ph.1 Diablo '6 Project Thread

Grooved discs give you a much improved initial bite and help at high temperatures, but do indeed cause additional pad wear.

It just really comes down to whether or not you feel the improvement in initial bite is worth the extra wear.

Oh, grooved discs make a cool noise too

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Rich

say it to specifically to me and not to "everybody" otherwise you just seem like a dick otherwise.

i never like to %100 anything hence using phrases like that. gives me a get out clause when some know it all knob face wants to proove he knows more becuase hes had the option to post afterwards

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the world is changed by people in sheds