350PsDMeuP

iTrader: (1)

yeah stoptech has slotted i was looking for drilled, any ideas?

Kurtz

iTrader: (1)

And for the 3rd time, modern brake pads haven't had issues with gassing since in decades.

If you don't believe me then believe the brake engineer I just quoted to you who has literally written books on brake systems and is a consultant to Stoptech and has worked for several large car makers among others.

No matter how you built a drilled rotor it will be -more- prone to cracking than an equivalent solid one. No matter how you built a drilled rotor it will have a lower heat capacity than an equivalent solid one. It's basic physics.


Here's something telling BTW-

Porsche cars in the showroom have drilled rotors.

Porsche race cars don't

Here's one discussion that mentions it-
http://grassrootsmotorsports.com/for...car/847/page1/

If you want more here's Wildwood:

Q: Why are some rotors drilled or slotted?
A: Rotors are drilled to reduce rotating weight, an issue near and dear to racers searching for ways to minimize unsprung weight. Drilling diminishes a rotor's durability and cooling capacity.

Slots or grooves in rotor faces are partly a carryover from the days of asbestos pads. Asbestos and other organic pads were prone to "glazing" and the slots tended to help "scrape or de-glaze" them. Drilling and slotting rotors has become popular in street applications for their pure aesthetic value. Wilwood has a large selection of drilled and slotted rotors for a wide range of applications.


Or Stoptech:

DRILLED VS SLOTTED ROTORS

For many years most racing rotors were drilled. There were two reasons - the holes gave the "fireband" boundary layer of gasses and particulate matter someplace to go and the edges of the holes gave the pad a better "bite".


Unfortunately the drilled holes also reduced the thermal capacity of the discs and served as very effective "stress raisers" significantly decreasing disc life. Improvements in friction materials have pretty much made the drilled rotor a thing of the past in racing. Most racing rotors currently feature a series of tangential slots or channels that serve the same purpose without the attendant disadvantages.

al503

I'm not disputing this. I apologize for not being clearer. For the last time, my point is that slotted/drilled rotors may offer the manufacturer some flexibility in their pad choices. I've re-read my previous posts and don't see any indication that I disagree with you here. If there is, then my apologies again.

I agree. All other things being equal, the drilled will, by definition, be more prone to cracking and have less heat capacity. I wasn't arguing otherwise. My point was that the drilled rotors can be overdesigned/overbuilt so that cracking/longevity is not an issue for the car they will be installed on. Put another way, you can probably take the huge rotors off of a Veryon, drill holes in it within reason, put them on a Lotus Exige, run the Exige on the track all day long and the rotors probably wouldn't fail.

So, Let's sum all of the points that I'm actually arguing in this thread and you're more than welcome to agree/disagree/comment.
1. since we agree that gassing isn't an issue, slotted and/or drilled rotors can help performance by giving dust an avenue of escape between the pad and rotor.
2. Drilled and/or slotted rotors may give the manufacturers some additional flexibility in pad material choice.
3. Drilled/slotted rotors can be overbuilt/overdesigned so that cracking/longevity issues are not an issue for a particular application.

Now you're putting words in my mouth. I never claimed that drilled were better for racing applications. Take a look at some of my previous posts on this subject: https://www.clublexus.com/forums/sho...ghlight=rotors

Call J Ritt at Stoptech. Ask them about x-drilled rotors. They offer them for the street and show but recommend against them for the track.

Cooling/Thermodynamics argument:
1. a properly vented (internally) rotor will have sufficient flow to disperse the heat without cross drilling.
2. by cross drilling you reduce overall mass and you actually decrease the surface area (needed to dissipate the heat) of the rotors.

Whether you're doing 1 emergency stop or 10, the solid, properly vented rotor will always be cooler than the same rotor that has been cross drilled.

How many F1, Indy, Nascar, etc., race cars have you seen with cross drilled rotors? I haven't.

Have you taken a speed reading course or something. I don't mean this in a negative way. Just curious.

passnu2

iTrader: (33)

You have PM...hope that helps if you didn't get anything yet!

Mike

350PsDMeuP

iTrader: (1)

got it, thanks!

IAMJAVEDG

iTrader: (5)

www.brakeworld.com ! they got some nice BREMBO front rotors for a NICE price! and they got some other brands for the rear...

Koz

http://brakeperformance.com/site/bra...0408&ad=google

Koz

mitchsti

iTrader: (1)

ebc offers slotted and dimpled rotors i have them on my 07 is350 work great little bit of noise from slots

tennisstar

[QUOTE=350PsDMeuP;3753750]ive heard bad things about lextasy, can anyone vouch for them? in addition, do the 250 and 350 have the same rotor size, but different calipar sizes or whas


stay away from Lextasy.com.....they sell junk and poor cust. service to boot!

carchitect

iTrader: (1)

I used EBC stuff on my CBR900 and they sucked compared to the OEM honda pads. I used EBC on the integra and they sucked also compare to the OEM. I said the hell with it and stuck with OEM.

The Is350 is on OEM high dust pads and I love them. I hate the lack of COF from the low dust pads so I don't use them.

The OEM rotors are a soft material. I think Racing Brake.com makes great rotors. They are used on several NSXs and are 2-pc and lighter. They are about $650/pair but are well worth the upgrade for a rotor that doesn't show a lot of wear and will last longer.

Byprodrive

iTrader: (1)

Anyone tried Cryogenic treating "freezing" of thier brake rotors?

Any noticable differance?

carlos

iTrader: (1)

are those lighter than the stockers?

iSuxeL

iTrader: (21)

What ever you guys do, DO NOT BUY FROM BSIBRAKES they're the most F'd up company ever!!!! I repeat DO NOT buy from them. I bought rotors from them since Feb. still haven't seen anything, I got them to refund me the money after 2months of trying and still nothing. Now they won't even pick up my phone calls!!! I left message after message and they won't call me back.....F!@k I'm so pissed....

carchitect

iTrader: (1)

Yeah, You'll loose anywhere from 3-5 lbs per rotor. Thats unsprung weight. The rotors are designed to "float" on the hardware too.