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This question has been raised in another thread which was really about prices of Bendix pads so I thought I'd move the discussion to a thread of its own.
The context of the discussion centred around a few issues:
1. the real benefit of aftermarket pads vs. standard OEM;
2. slotted rotors vs. standard; and
3. cross drilled rotors vs. standard and slotted.
My experience has shown that slotted / cross drilled rotors on the street provides little gain over a ventilated but solid (smooth) disk. For this reason I believe that apart from looking good these are a waste of cash and that the extra would be better spent replacing warn rotors twice as often.
My experience has also shown that brake pads differ greatly, and that the OEM Prado ones are garbage. They offer no bite and plenty of fade. They are quiet and almost dustless which is a plus but not enough of one that I am prepared to trade off against performance. Afterall brakes are there to work and if they look good then that's a bonus. I sure don't want to be in someones backend, sitting on the kerb as the tow truck is towing my Prado away thinking 'gees my brakes are pretty'
Here's the start of a flyer put out by Repco. It has DBA, Ferodo, PBR, ALcon and Bendix advertisements plastered all over it so I'm assuming they probably vetted the info for accuracy but it doesn's say so I can't be sure. I'd say that this was likely though. It provides an interesting read.
So what is everyones thoughts?
Full article link: http://www.repco.com.au/CA2571B70016384 ... 45-151.pdf
The context of the discussion centred around a few issues:
1. the real benefit of aftermarket pads vs. standard OEM;
2. slotted rotors vs. standard; and
3. cross drilled rotors vs. standard and slotted.
My experience has shown that slotted / cross drilled rotors on the street provides little gain over a ventilated but solid (smooth) disk. For this reason I believe that apart from looking good these are a waste of cash and that the extra would be better spent replacing warn rotors twice as often.
My experience has also shown that brake pads differ greatly, and that the OEM Prado ones are garbage. They offer no bite and plenty of fade. They are quiet and almost dustless which is a plus but not enough of one that I am prepared to trade off against performance. Afterall brakes are there to work and if they look good then that's a bonus. I sure don't want to be in someones backend, sitting on the kerb as the tow truck is towing my Prado away thinking 'gees my brakes are pretty'
Here's the start of a flyer put out by Repco. It has DBA, Ferodo, PBR, ALcon and Bendix advertisements plastered all over it so I'm assuming they probably vetted the info for accuracy but it doesn's say so I can't be sure. I'd say that this was likely though. It provides an interesting read.
So what is everyones thoughts?
Full article link: http://www.repco.com.au/CA2571B70016384 ... 45-151.pdf
Cross Drilled and Slotted Rotors
The recent rise in popularity of these discs has raised confusion as to the right products for particular applications.
As we know, most brake discs have a smooth, flat surface. Holes and slots in the face of the disc have a number of purposes.
The first is to remove gasses from the face of the disc. Disc pads, when hot, expel gasses. These gasses form a cushion between the face of the disc and the pad, and can greatly reduce the co-efficient of friction.
It takes a tenth of a second to squeeze these gasses out on normal rotors. This does not sound like a long time - but consider this. When a vehicle is travelling at 100 km/h, it is moving at a rate of 30 metres per second, therefore a tenth of a second is three metres. So when the brakes are applied the vehicle travels for three metres squeezing out gases and not creating friction to slow the vehicle.
Another problem that occurs when the build-up of gasses is not released is that the pad material becomes hardened and glazed, greatly reducing the amount of grip between the pad and disc. Crossdrilling and slotting allow these gasses to be moved immediately, also helping to deglaze the pads, increasing the grip between the pad and the disc, hence shortening the braking distance. Cross-drilling and slotting makes the disc surface uneven so, water and dust cannot develop into a thin layer that becomes a smooth, glass like surface which can greatly reduce the coefficient of friction.
Cross-drilling and slotting works effectively to reduce the main problems that occur in brake systems. But there are some tradeoffs, such as reducing pad life by approximately 10 per cent (if you’re getting 40,000 km from a set of pads this can be reduced to 36,000 km, though most would agree this is a small price to pay for better braking performance). Also, the cross-drilled rotors are more prone to cracking under extreme conditions, such as racing.
In normal motoring the slotted-only and cross-drilled and slotted rotors have similar performance qualities.
So the question is: do I fit cross-drilled and slotted discs, or just slotted discs?
This question has to be asked: what is the main purpose of the vehicle? Is the vehicle used for racing or is it just driven extremely hard? Does the vehicle go off road? If the answer is yes to either of these questions, slotted-only discs are the best choice.
If a vehicle is only used on the street, but is occasionally driven hard, and has nice open wheels where the rotors need to look good as well as perform, cross-drilled and slotted rotors are the way to go.
The recent rise in popularity of these discs has raised confusion as to the right products for particular applications.
As we know, most brake discs have a smooth, flat surface. Holes and slots in the face of the disc have a number of purposes.
The first is to remove gasses from the face of the disc. Disc pads, when hot, expel gasses. These gasses form a cushion between the face of the disc and the pad, and can greatly reduce the co-efficient of friction.
It takes a tenth of a second to squeeze these gasses out on normal rotors. This does not sound like a long time - but consider this. When a vehicle is travelling at 100 km/h, it is moving at a rate of 30 metres per second, therefore a tenth of a second is three metres. So when the brakes are applied the vehicle travels for three metres squeezing out gases and not creating friction to slow the vehicle.
Another problem that occurs when the build-up of gasses is not released is that the pad material becomes hardened and glazed, greatly reducing the amount of grip between the pad and disc. Crossdrilling and slotting allow these gasses to be moved immediately, also helping to deglaze the pads, increasing the grip between the pad and the disc, hence shortening the braking distance. Cross-drilling and slotting makes the disc surface uneven so, water and dust cannot develop into a thin layer that becomes a smooth, glass like surface which can greatly reduce the coefficient of friction.
Cross-drilling and slotting works effectively to reduce the main problems that occur in brake systems. But there are some tradeoffs, such as reducing pad life by approximately 10 per cent (if you’re getting 40,000 km from a set of pads this can be reduced to 36,000 km, though most would agree this is a small price to pay for better braking performance). Also, the cross-drilled rotors are more prone to cracking under extreme conditions, such as racing.
In normal motoring the slotted-only and cross-drilled and slotted rotors have similar performance qualities.
So the question is: do I fit cross-drilled and slotted discs, or just slotted discs?
This question has to be asked: what is the main purpose of the vehicle? Is the vehicle used for racing or is it just driven extremely hard? Does the vehicle go off road? If the answer is yes to either of these questions, slotted-only discs are the best choice.
If a vehicle is only used on the street, but is occasionally driven hard, and has nice open wheels where the rotors need to look good as well as perform, cross-drilled and slotted rotors are the way to go.
photoprado
), but I think I might still fit the cross drilled since theyre on their way and see how they go. if they prove to be duds on and offroad then at the very least ill have real world experience and be wiser for next time, and I wont be out of pocket a great deal. its still not a direct comparison but better than nothing. Ill post up my thoughts after installation and after Ive had them for a while.
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