You make the call:D

Some of you might have been before, but most probably have not. It a good read.

www.altimas.net/forum/showthread.php?s=&threadid=32327&pagenumber=1

I have cross drilled rotors on my GTR in the front, solids in the rears. They do have advantages in providing release ports if you will for break dust, dirt, and the gases that the break pads produce.

How ever they also weaken the rotors. I have seen many crack under hard usage on the same car as where the solids don't.

Tough call on factory rotors but aftermarkets could be different.

Brakes are a heat sink, take mass away from that heat sink it will become less efficient.

Did you happen to read that thread?

i've read that both (cross drilled and slotted) are good... depending on the argument..

porsche uses factory cross drilleds on alot of stuff, but i've heard slotted to be better...

apparently, cross drilleds heat up quicker, stay hotter, etc...
if something gets stuck in a hole, it'll screw your pads, etc...

they don't crack (slotted) compared to cross drilled... but it depends on the holes. forged holes in the rotors won't crack like drilled holes will.
it depends on the structural integrity...

a rotor that's forged with the holes is stronger, which saves face for that side...

but companies like stoptech and what not used slotted...

but brembo makes drilled... so?

but brembo makes drilled... so?

So, they must be good:)

porsche uses factory cross drilleds

Are sure they are cross drilled, or forged. Plus they probally cost more than what my GTR cost?

i'm referring to the rotors with holes generically as "cross drilled"

they may be forged...

my point was that two major companies that know alot about brakes and are renowned for them use "holed" rotors...

but slotted is just as good...

i guess it depends on the money you wanna spend...

i guess it depends on the money you wanna spend...

But also making an informed decision, not what some sales person is feeding in your head.

that i'm well aware of...

alot of track racers (www.nsxfiles.com) would agree on beatin the shit out of holed rotors...

but he never states why one way or the other...

he does note that they crack after getting on the track, but that's to be expected...

i've seen alot of major cars, le mans type racing, using slotted...

it's all about the money depending on everything...
i don't base decisions on what some guy says i should get, i usually look at user feedback (not on a manufacturer's site)..

and... porsche feedback is always noting the amazing brakes... is it b/c of size, b/c holed over drilled, or calipers? i dunno...

that i'm well aware of... Yes, but is everybody?

if they all were...

we wouldn't have to have this "debate"...

and people wouldn't run on bald tires, and people would get their oil changed on time...

there's so much that we assume people know b/c they have something on their cars...

like upgraded brakes...

when in reality, it's just what someone said they should get and they bought it...

since i'm at work, and i get to read all sorts of cool tech stuff,
we just got this email from power-stop... about slotted rotors...

At one time the conventional wisdom, in racing circles, was to cross-drill brake rotors in an attempt to aid cooling and eliminate a phenomena called out-gassing that actually inhibits brake efficiency. Today elite teams in Trans Am, Indy and World Rally racing have abandoned crack prone, cross-drilled brake rotors in favor of a fatigue resistant slotting process. This process removes far less surface area than conventional cross drilling and maintains the highest possible co-efficient of friction. Power Slot rotors are specifically designed to run cooler, promote improved wet and dry brake performance and extend brake life.



The Power Slot rotor represents the most cost efficient bolt-on, performance brake, upgrade offered today. All Power Slot rotors are CNC machined in their Chatsworth facility to application specific tolerances that utilize an exclusive, patent pending, Power Slot “Vac-U-Slot” technology. This technology preserves outer edge rotor strength, while aggressively forcing brake dust, out-gassing and heat to vent. The exclusive bright silver, anti-corrosion Cadmium plating, done to military spec, adds a high-tech appearance that enhances the visual impact of custom wheel installations over long period of time.





i'm aware that it's a sales type email to give companies information when selling a product, but that's what i've read on slotted rotors from other places as well...

Originally posted by SkylineUSA


Are sure they are cross drilled, or forged. Plus they probally cost more than what my GTR cost?

Not sure what you would pay for factory rotors. I have looked into here as my "holed" fronts are getting tired and a bit thin. The best price I can find is around $300 NZD a rotor here. I can upgrade to an after market set but because they are 300mm dia only a few places make actual upgrades and they start at $4,800 for the fronts alone, and that is for 350mm dia ! Of couse that means also a caliper upgrade to boot.

People can talk all day about holes and slots and carbon/carbon....what ever. These are the same people who fall for sparkplug gaskets, super duper coil wires, mufler exhaust grease etc...

In most cases the non professional racer (non-race prepared cars that are not endurance raced) will never know the difference, never feel it in the seat of the pants, and never push their cars anywhere near the limit where special rotors are neccessary.

That said there was an article posted by someone in the corvetteforum from Porsche's engineering chief who said the only reason Porsche finally started using "holed" rotors is because everyone else was doing it, and it becomes hard to sell a six figure car with-out all the bells and whistles that others have! Another case of ignorant consumers driving the market.

In most serious sports cars the braking systems already out perform the tires and track conditions when they are pushed to the limit. Your money would be better spent on quality tires, stainless steel brake lines, and quality brake fluid. If however you feel serious racin ambitions then upgrade to a better pad. Racing pads won't work well on the street and they will eat up rotors quickly. If you aren't pushing your car hard enough to be changing rotors, tires, and wheel bearings at least every half dozen races or so, then you probally don't need specialty rotors, unless you just like the look. In which case you are a waxer and not a racer, thus your question becomes a dress-up rather than a performance question.

just my 2 cents...

AL

People can talk all day about holes and slots and carbon/carbon....what ever. These are the same people who fall for sparkplug gaskets, super duper coil wires, mufler exhaust grease etc...

Sparkplug gaskets and muffler exhaust grease? WTF? Umm I thought ever spark plug came with a compression gasket washer, I could be wrong. Never heard of the latter though.
As far as larger dia coil and plug leads (wires) they do have benifits even with a standard engine though it is like a bit of over kill and a waste. The do conduct and transfer electricity much more efficently. They are especially good for supercharged or turbo charged applications where spark consistantcy is very important.




In most cases the non professional racer (non-race prepared cars that are not endurance raced) will never know the difference, never feel it in the seat of the pants, and never push their cars anywhere near the limit where special rotors are neccessary.

That is incorrect. By increasing the rotor diameters you also increase the actual stopping surface avialable. Also by incrasing the diameter you increase the stopping power providing your tyres can sustain it. With that you also are not requied to apply as much pressure or force with the pads against the rotor to achive the same braking power, thus also reducing pad temps. Also when you increase the rotor diameters you have to change the calipers due to the new diameter of the rotor. That in itself means they will match the rotor and will be much stronger with less flex and again great stopping power with much less effort.



In most serious sports cars the braking systems already out perform the tires and track conditions when they are pushed to the limit. Your money would be better spent on quality tires, stainless steel brake lines, and quality brake fluid. If however you feel serious racin ambitions then upgrade to a better pad. Racing pads won't work well on the street and they will eat up rotors quickly. If you aren't pushing your car hard enough to be changing rotors, tires, and wheel bearings at least every half dozen races or so, then you probally don't need specialty rotors, unless you just like the look. In which case you are a waxer and not a racer, thus your question becomes a dress-up rather than a performance question.

Well I own a Skyline GTR. After a few laps at a local track I would have nearly zero stopping power. Due to the fact there are two extremely tight sections that preceed long straights where even a midly tune car such as mine is capable of over 220kph then down to a hair pin on one section and a S-series on the other. Also during some spirited driving on a long trip I experienced brake fade. While not pushing the overall speed, I was in fact diving deep into the tight twisty corners. After about 40mins of this the amount of brake fad was extremely noticable. I also in fact have uprated semi-metalic road/light duty track pads, that and also high temp DOT4 brake fluid.
The plain fact is the pads over heat quickly. Changing the pads will help and also the brake fluid to a high temp dot4 racing fluid, but as mentioned before I am still required to apply much greater force to stop thus I am not lowering the brake temps only extending what the gear I have can sustain it for a bit. Those same pads with a rotor of greater diameter will help drop the temps down. Also putting in brake ducting but we are talk about street use and not practical.
Speak about pads for a moment. For the daily use there are some decent upgrades which while extending the operating temp range without sacraficing too much low temp operation are available. They will give decent performance in a daily use car even cold. Yes going to full racing pads for a street car is not a good idea as they may have an operating temp that beings where a standard street pad stops or even later.

Matching the rotor to the proper caliper is also important. changing from a 200mm rotor to a 320mm rotor and using a cheap caliper to suit that diameter obviously not such a good idea but mate with with say a 6 pot (6 piston) caliper or a very large 4 pot such as Alcon or AP and you have a very good combination.
Rotor design also plays a critical part. One that does not cool down quickly and retains heat is not so good. It does not matter whether it is cross drilled, forge holed, sloted, etc.
Next is rotor thickness. A thin rotor will dissipate heat quicker than a large solid thick rotor. It will also heat quicker, crack eaiser, and over heat easier. The thicker single walled rotor will hold up better overall but also not dissiapte heat quickly. Next you would have the double sided rotor as found as an example on a late 80's GM car like the Camaro Z28. It has cooling fins that split the front to back wall of the rotor. As the rotor turns these fins act like a radiator for the rotor helping cool it down. Rotor design plays as big a part as overall size.
Full race spec rotors come in so many flavours I could be here all day going over each one. If you look at them they are plain and simply huge. There surface area is a sustantial increase over even a normal rotor and brake upgrade the average person is willing to or can afford to spend on.
:)

i'm also on the same front and disagree.

my factory brakes are overwhelmed after about 10 minutes of very hard driving on some twisty roads...
my upgraded rotors and pads take the same roads and speeds without flinching...

i'm not a racer by profession, but i'm a hard driver and i push my brakes to the limit...

the limit doesn't come from extreme driving either... it comes from extreme usage... the more you use your brakes in a short amount of time, the hotter they get, the less the pads grab, blah blah blah.

even the upgrade on a regularly driven car will make a difference.

will the average driver notice the difference? no.
will the person that is upgrading their brakes for these reasons? yep.

regardless of holes/slots/solid...

upgraded brakes make a difference on any car.

changing your pads alone to something less organic and more carbon or ceramic makes a world of difference in repeated usage.

you can't claim that it doesn't work and that it's a gimmick. sorry. that's not going to fly

Razor GTR,

Sparkplug gaskets, super duper wires, and mufler bearing grease is a joke! I can't believe you haven't heard that before. It's like sending someone for a two feet of drag strip. Just tryin' a little humor... tough crowd!

As for coil wires I think they are still a gimick, especially without a better ignition module. As you alluded to, in certain applications such as turbo, supercharged, nitrous, or high compression an improved ignition can have noticeable benefits. Personally MSD has got the right product in their multi spark discharge units. Crap like split fire is a joke. (Electricity travels the path of least resistance, and it takes the shortest path. There will be only one arc off the electrode not two.)

Regarding brake upgrades, I refered to serious (purpose built) sports cars. Sure their are plenty of everyday cars that could use brake upgrades if pushed beyond their intended grocery getter limits. Hell even a school bus would notice brake fade if pushed hard enough. However, I was refering to cars designed for street and track duty. I have not heard of anyone championing a stock Porsche or corvette in SCCA/NCCC sactioned events complaining of undue brake fade.

I was under the impression that the GT-R's Brembos were pretty decent brakes? I have never driven a Skyline so I couldn't tell you. My old mustang GT was terrible. Two passes down the quarter and it was fade city. But then again that's not what Ford designed it for...

AL

flylwsi,

Sorry, I wasn't trying to offend anyone. The vein I started off on was speaking of racing and purpose built street/track cars. I wasn't trying to cover every car on the road.

If you considder every car out there, sure many could and would benefit from brake upgrades. But I do not believe that street driving, no matter how spirited, will resulted in pad out-gassing that requires slotted rotors. If thats the case then you need to think about a fuel cell, fire resistant long johns, and a helmet. ;)

For the record, holes, slots, dacing bears... all a gimick.

AL

It is all good guys, seriously :)

i don't want anyone being offended by good discussions. Speaking of which I really should split this thread and move the discussion about rotors and such as a new thread.

I will think about it since I am at work currently and haven't woken up 100% yet.

well...
as my car is underbraked when i put bigger/heavier wheels on it, yeah, i was able to out use the life of the brakes...

my upgraded brakes and pads help tremendously..

of course, the road i'm driving may as well be a racetrack... 60+ for the whole thing, high rpms, and super tight corners everywhere...

not really street driving, more like unofficial track time...