# cross drilled rotors on ebay



## Nismo1997 (Dec 26, 2003)

what do u think of the cross drilled rotors on ebay? think its worth it?


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## NotAnotherHonda (Aug 7, 2003)

i f you really dont ever thnik your gonna go a brake upgrade later, then ide do it


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## himilefrontier (Jan 21, 2003)

I would skip it for a street car. Slotted rotors are better as drilled ones are much more crack prone. Also, early (95-97) B14 rotors are known to be unstable under anything but light use and will warp badly if you stop hard and hit a puddle! The holes would only increase the chances of craking them under severe heat cycling and for that reason, I would not use them. If I were to do anything, I would do what everyone else does :upgrade to AD22VF brakes from a 1991-93 NX2000 with ABS and made in Japan. Thicker , larger rotors and bigger caliper pistons make for a great upgrade in both performance and reliability. Do a SEARCH and you will find all of the information you will ever need on this upgrade.


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## ReVerm (Jan 13, 2003)

himilefrontier said:


> I would skip it for a street car. Slotted rotors are better as drilled ones are much more crack prone.


Sorry to go a bit off topic, but recently I'm seeing a lot of this anti-cross-drilled rotor cultism going on around here (This is in no way directed at Himilefrontier. He's probably one of the few regulars in the Suspension & Brakes that have not mindlessly submitted to this view). And I can see where it's coming from too, with people going back and looking at those posts when Won't Be Beat frequented these boards. It certainly is true that cross-drilling the stock rotors on a B12, B13, or B14 Sentra will do very little good, and that slots are a slightly "safer" solution when getting stock-sized replacement rotors. However, we must realize that cross-drilling rotors is far from useless, even on the street.

Let me start by clarifying a few things about cross-drilled rotors: Cross-drilling your rotors won't help brake cooling a significant amount (though it apparently does help, though the differences were always only a few degrees), and it will make the rotors more crack-prone than blank discs. Cross-drilled rotors will allow space for gasses and debris to escape through, as it will clean the underside of the pad and help with initial pad "bite" though will not appreciably increase the braking power of the system noticably. There is a point in brake disc applications, where cross-drilled holes will do the same thing as slots but with far less reduction in surface area or structural integrity. This is why the top JGTC, DTM, and Japan F3000 series teams ALL use cross-drilled rotors. They DO NOT use slotted rotors (and no, this does not directly relate to the fact that ceramic on ceramic brakes are allowed in the JGTC).

What a lot of people here just seem to assume but not understand is that these advantages only apply to circuit driving. This is far from true. Many of the advantages listed above can readily be realized on the street: If you drive through a lot of dusty areas (i.e.: places with a lot of construction zones), muddy areas (i.e.: anywhere which gets a lot of rainfall), or if you just like to overheat your pads, the holes in the rotors will allow those materials to escape into the vented center of the rotor and out from the rear. In the case of debris, this will help prevent that annoying comes-and-goes brake noise that people complain about. In the case of brake dust, it will actually help PREVENT the rotors from accumulating runout (and yes, this has been lab tested). The cross-drilled holes will help keep gasses from accumulating under the pad when the pads start to fade, and if you run pads with very little initial grip (Hawk HPS's for the street), the "initial bite" effect is quite noticable. Rotors with slots that do not penetrate the rotor will not help brake gasses escape, and it will not clean anything off of the pads once the slots get filled with crap (which does happen).

All of the above assumes two things about the cross-drilled rotors in question. The first is that the rotor has been cross-drilled properly and the holes have been chamfered, This means that a rotor on which joe mechanic reproduced the hole pattern on a porsche rotor using a hand drill, then filed down the edges with a hand file may very well make the rotor worthless. The second is that the hole pattern has been thought through by engineers who know what they're doing. A cross-drilled rotor is not a cross-drilled rotor is not a cross-drilled rotor. There are hole patterns out there that make people like me, who know only the basics of mechanical engineering, go "wtf is this garbage?". Incidentally, the above are the most valid reasons to tell people to avoid cheap cross-drilled rotors on eBay which aren't accompanied by photographs of the actual rotor being shipped to your home, and are what Won't Be Beat really has strong opinions against.

I am not saying that we should all go out and buy cross-drilled rotors. I still support the adage that has developed on these forums that stock-sized, cross drilled rotors are a waste of money on any pre-2000 Sentra. I just want to keep everyone from falling into a habit where they just say "don't get that. It sucks" to something as potentially useful as cross-drilled rotors.


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## himilefrontier (Jan 21, 2003)

Thnaks for the clarification! I am not opposed to crossdrilled rotors , but do not like them in certain crack and warpage prone cars like B14's and Fox bodied Mustangs. They do have their place on a race car (and some street cars) , but E Bay rotors are far from race car rotors! They may be straight and true, but there is a big difference in quality from what some Chinese slave laborer casts and what is made by a reputable brake company. The materials and alloys used in race car rotors are also different and they are a part of why they are so good.To me, $100 is a lot to spend on a set of rotors that will be little better (if at all) than stock when you could do the AD22VF upgrade for not too much more (If you shop around).Save your money, and if you need brakes right now, get a cheap set of pads to tide you over while you are saving up for the upgrade.


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## Nismo1997 (Dec 26, 2003)

ill looking around for the ser rear disc brakes. i like how the look and they cant be that bad..im not saying there the best but u get wha im saying?


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