cross drilled or slotted

[ole dsm]

just curious

whats the best rotor to use for regular spirited driving?
can u use slotted in the front and cross drilled in the back? or vis. versa

also can one use oem pads on such rotors? with out doing damage to the rotors?

what are the best brands? or best bang for the buck?




thanks

[T5_X]

I would go with cross drilled, as slotted will wear down your pads faster.

You can use any type of pads with either kind of rotor.

[autospeed]

you should be able to use stock pads on slotted and vented rotors but its kinda pointless cause pads can make a huge difference in your braking performance. Upgraded pads on stock rotors can make a huge difference. But as far as cross drilled or slotted i'd say cross drilled would do nicely but that's more of a personal pref i guess they would probably evacuate the heat slightly better too (imo) but you can rotors with both done to them. Brands i'd say just look around there's a lot of companies makin decent one piece rotors like that. Brembo is awsome but they can get pricey depending on what you're looking for. I think HP Racing has some nice one piece rotors at a really good price too.

[autospeed]

but the high performance pads on the stock rotors can wear the rotors out really really fast so be careful.

[buh_buh]

actually cross drilled rotors are prone to cracking.
I would go with slotted.

[itsnotaDUB]

get slotted crossdrilled rotors

[GTS Jeff]

u can do both if u want. id stay the fark away from slotted cuz the slots slice away at your pads. this is good for track cars cuz the slots will slice away glazed parts of the pad and also keep it free of dirt/grime/water...but again, itll chew thru your pads so its not a great idea for a street car.

buh buh, slotting weakens rotors just like drilling, the trick is to use a high quality and thick rotor blank when drilling or slotting so that the shit wont crack.

[Ben]

If cross drilled is good enough for all of Porsches cars ...its good enough for mine

[EK 2.0]

Originally posted by Ben
If cross drilled is good enough for all of Porsches cars ...its good enough for mine

Word man...

BUT...if it is for your DSM Power Slot makes an AMAZING Rotor...its only slotted, but tested over and over by DSM guys AND gals...

[m10-power]

Originally posted by Ben
If cross drilled is good enough for all of Porsches cars ...its good enough for mine

Well there is a big difference between Porsche factory brakes and some aftermarket 'Drilled' rotor. Porsche OE rotors have the holes cast in during production not drilled after.

Go with slotted if you must but I don't see the point unless your road racing or doing track lapping days.

[redline]

Originally posted by Ben
If cross drilled is good enough for all of Porsches cars ...its good enough for mine

read porsches web site as to why they use drilled rotors and talk with some porsche own that track the cars and see what they think of cross drilled rotors.

[Ben]

fuck, talk about taking things way to seriously

[1badPT]

Originally posted by GTS Jeff
u can do both if u want. id stay the fark away from slotted cuz the slots slice away at your pads. this is good for track cars cuz the slots will slice away glazed parts of the pad and also keep it free of dirt/grime/water...but again, itll chew thru your pads so its not a great idea for a street car.

buh buh, slotting weakens rotors just like drilling, the trick is to use a high quality and thick rotor blank when drilling or slotting so that the shit wont crack.

There are also "dimple drilled" rotors which are structurally stronger than cross drilled rotors, but still offer most of the heat dissipation qualities of cross drilled. Depending on airflow, you might even get better cooling performance because dimple drilled have more surface area which helps in dissipating the heat.

[1badPT]

Here is a dimple drilled rotor (it has slots too which imo is not worth putting on a street vehicle - but its your wallet, if you wanna open it for new pads more often, suit yourshelf).

[ApexDrift]

dont know much bout breaks so i might as well ask... whats the difference with normal rotors and cross drilled and slotted rotors?

[ApexDrift]

nvm i understand now

[1badPT]

Originally posted by ApexDrift
dont know much bout breaks so i might as well ask... whats the difference with normal rotors and cross drilled and slotted rotors?

Cross drilled increases surface area to allow for better heat dissipation.

Slots cut away the top layer of your brake pad so that "fresh" brake pad is in contact with the rotor, slowing your car down faster. Its used to combat glazing which occurs when you use your brakes intermittently under high stress (IE when racing on a track - nailing the breaks to slow down for a corner, speeding up after the corner to jump on the brakes again for the next corner). What happens is your pad will glaze (imagine poishing metal so smoothly that it becomes slick) so you need to cut the glazed surface off the pad, which is what the slot does.

You can get rotors with either or both. Drilled won't screw up your pad life too much but slots will.

[lude_conduct]

The idea behind cross drilled rotors was definately not more surface area. It was when brake pads were still made of asbestos and created gas when they were heated. Thus, they needed the gas to vent. Now however, we have metallic compounds, that do not release a gas when heated.

The main problem people will have with their brakes is not the fact it does not cool down fast enough, but the fact that their brakes simply aren't heavy/big enough. The more weight it has, the more energy it can absorb, right? When you cross drill, you lose weight but don't gain an appreciable increase in surface area (in fact you get hardly any at all, that's directly exposed to the surrounding air). Coupled with the fact that the drilling process creates severe weakening of the rotor, there is simply no reason to purchase cross drilled rotors.

Why do you think LeMans and JGTC cars use blank rotors?
There is a slight (very slight) advantage to using slotted rotors, but it's personal preference.

As well, do you think the brakes on a Porsche 911 are really comparable to the set that you'll be picking up? It's not a fair comparison. As well, they are cast/forged with the drilling, unlike drilling a blank, so their is not a loss in strength.

So to answer the question, try and get a bigger set of blank rotors, a good set of pads, stainless steel brake lines, and good brake fluid. You'll notice a big difference in the total braking distance and how it feels.

[1badPT]

Its not a track application that he's asking for, and for today's applications, cross drilled offers heat dissipation and a slight reduction in unsprung weight. That's it(except for perhaps style). You may not feel that the extra surface area makes any difference, but you forget the wheel is spinning at a high rate of speed, which means you are moving a lot of air over the surface of the rotors - even a small increase in surface area will get the rotor temperates back down quickly.

Going with bigger rotors means you have to go with a "big brake conversion" - you're making it sound like you can just slap on some bigger rotors and steel lines and go, which couldn't be further from the truth. Depending on the car, this can be a pretty big procedure.

Steel lines just reduce flex in the lines and you'll only notice the advantages of a good brake fluid if your in a track situation (repeated heavy braking). Low grade brake fluid "boils" when the you are doing repeated heavy braking, which introduces air into the lines, which contributes to brake fade.

[EK 2.0]

You know...even from when I worked in the trade...Just bleeding your Brake System and adding fresh DOT 4 or 5.1 makes a HUGE difference...you have NO idea how many customers I saw with new pads and rotors or shoes and drums who complained of "mushiness"...Fresh Fluid works wonders...


Kinda blows my mind how many so called enthusiasts forget about the brake system when slapping on Turbos and S/C's and the like...