brake rotors

Originally posted by 2ndAlero@Mar 12 2004, 06:17 AM
What it shows is that over the years GM has done nothing to improve the braking on their cars even while the cars have gained weight.

That's the major reason why the rotors warp. More mass to stop (energy), creates more heat, and creates a high potential to warp the rotors.

Ding ding ding! We have a winner. :thumbsup:

Long time, no see Rich.

[Fast Eddie]

Originally posted by Final-Reality@Mar 12 2004, 05:57 PM
You have an alero with aluminum drum brakes? I call BS on that...

I never said it was an alero, that's four wheel disc, all I said was I have A car :rolleyes:

Also alum dissipates heat much better than iron hmmm.

Eddie, when a car is stopping, the brakes have to be made of a metal that can ABSORB heat, no material other than ceramic can hold as much heat energy as iron can. Brakes are made out of iron, not aluminum.

Also, 2ndAlero is right, I've read that j-body and n-body cars had their brakes designed back in the early 80's (the first gen j and n bodies) and weighed several hundred pounds less each. Technology and saftey has driven the weight of the cars up, and GM neglected the braking systems until recently on them, and even still they're fairly inadequate for anything more than one or two panic stops...

[Fast Eddie]

Then come over here and I will let you take a magnet to the things and you can see they are alum. Its common knowledge that first gen datsun Zs had alum drums in the rear, know what you are talking about before flaming.

The brake system does not have to absorb the heat it just has to deal with it being given off, typically this is through absorption. Ceramic actually reflects the heat hence does not absorb as much but puts it back into the atmosphere (dissipation), thereby allowing it to ENDURE higher temps.

[b-spot]

Wow final.. you are just making a fool out of yourself left and right in this thread...

BLK03GXS hit the nail right on the head....My dad has been ASE cert for 20 yrs and every new class he has been to the theory has never changed....When you brake hard they heat up.....when you continue to stand on the brakes the hot iron, steel, aluminum, plastic whetever gets compressed thus warppage...He's always told me once you stop leave enough room to let off and roll a little bit....and don't put the petal to the floor when you do stop. Never seen him have warpped rotors and neither have I..just food for thought....and it can't hurt

http://www.nrcan.gc.ca/mms/canmet-mtb/mtbaluminum-e.htm

Maybe this with shed light on the "Aluminum Rotor" discussion. It's a Government of Canada website. And yes, you can buy aluminum brake rotors. A number of companies offer them. Do a search on Google.

That's bunnyed, I've never heard of that before.. I wonder how well they work?

It's simple physics, kinetic energy is turned into thermal energy (via friction) when braking. Aluminum does not hold very much heat, plus it's more ductile than iron or even steel, so I simply thought it crazy that such brake exists on a street car (but maybe a bike or a go-kart or something)

They have been available for motorcycles, moto-x bikes, and mountain bikes for some time now. I used to use aluminum rotors on my moto-x bike when I used to race.

As to how they work. I'm not sure, all I know is that they are making a variety of different modified aluminum alloys that stand up to heat better. I think the whole idea behind aluminum rotors is to reduce weight, and to disperse heat quicker. Think about it, most heat sinks are made of aluminum. The idea is not to retain the heat, but to disperse of it quickly. I'd be curious myself to see the theory behind it.....

[sound_xtreme]

#1 cause: people are bunnyin hard on their brakes, i had stock rotors unwarped up until 90,000 miles. the only reason they went bad then was because the caliper locked and i had to replace everything. you people must drive like maniacs to warp them, seriously.

Wrong! My wife's malibu went at 11,000 miles!! And she is definitely NOT hard on her brakes. Her dad taught her the RIGHT way to drive.

[sound_xtreme]

well i know mine were perfect for 90,000 miles explain that one. and my pads lasted a loooong time also. i'm not sure on the exact milage for those though. i know when my caliper locked my pads were pretty much brand new so my stock pads lasted for like 80,000 miles.

[brsexton]

Originally posted by sound_xtreme@Mar 14 2004, 06:22 PM
well i know mine were perfect for 90,000 miles explain that one. and my pads lasted a loooong time also. i'm not sure on the exact milage for those though. i know when my caliper locked my pads were pretty much brand new so my stock pads lasted for like 80,000 miles.

Just consider yourself ONE of the few lucky ones. I am not hard on my brakes either, and my rotors and brakes needed to be replaced at 16k on my Alero. The Pads and rotors on my Mazda lasted until almost 60k before they even started to warp.

Originally posted by mfuller+Mar 12 2004, 06:22 PM--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (mfuller @ Mar 12 2004, 06:22 PM)</td></tr><tr><td id='QUOTE'> <!--QuoteBegin-2ndAlero@Mar 12 2004, 06:17 AM
What it shows is that over the years GM has done nothing to improve the braking on their cars even while the cars have gained weight.

That's the major reason why the rotors warp. More mass to stop (energy), creates more heat, and creates a high potential to warp the rotors.

Ding ding ding! We have a winner. :thumbsup:

Long time, no see Rich. [/b][/quote]
That's funny because I'm sure that my Alero is lighter than my '80 cutlass and my '85 grand prix.

So what I think you guys are trying to tell me is that both of those cars could out brake my alero? I hardly think so.

there's alot more to a rotor than you might think... not even every rotor coming off a GM supplier's line is the same.

GM specs require certain consistency and material qualities... the company bidding the lowest gets the contract. that company is also the one skimming by with the BARE minimum as far as input materials go.

say 10% of the material the supplier purchases is of superior quality for rotors.

another 70% is average - it'll do, but its really the minimum for satisfactory performance stacked against GM standards (low to begin with)

the last 20% is inferior material. it sucks.

the supplier is pulling 1 out of 50 rotors (that is a guess, but whatever it is, its also spec'd and audited by GM) and testing them, and with the input being 80% good, the tests are well within specs for quality and get shipped to GM. GM is more than likely testing far fewer if at all, and thus is putting them on the cars in good faith (sort of).

what does this all mean? well, it means 20% of alero owners are getting crappy brakes that suck. another 10% are getting great results. and the rest are satisfactory (well, it depends on your own standards i guess).

makes sense to me... couple the ongoing battle with quality vs competitive prices and you get a fat chance of getting a perfect car.

course... this has nothing to do with performance really. if GM wanted you to be braking the best they'd be throwing on oversized performance brake packages - but then my grandma would be calling and complaining to GM to no end that the brakes are too grabby and when she had to replace them after 70,000mi (yes, good brakes wear out too) she'd call and complain that they cost twice as much as her corsica brakes did! now, GM wouldn't want that whole age group that is over 60 that represents 67% of its customer base bitching about that would they? HELL NO!


^^ the above represents 10% actual knowledge, 30% on-the-job experience, and 60% speculation. man i wrote alot more than i was planning on.

[AlbinoMonkeyRat]

Originally posted by velocity+Mar 14 2004, 10:21 PM--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (velocity @ Mar 14 2004, 10:21 PM)</td></tr><tr><td id='QUOTE'>

Ding ding ding! We have a winner. :thumbsup:

Long time, no see Rich.

That's funny because I'm sure that my Alero is lighter than my '80 cutlass and my '85 grand prix.

So what I think you guys are trying to tell me is that both of those cars could out brake my alero? I hardly think so. [/b][/quote]
maybe we're just using the same rotors as the J-bodies? :unsure:

[smokinAMD]

I still have the stock rotors at 42k miles, I just recently changed the front pads, rears are still the original.

[b-spot]

Originally posted by sound_xtreme@Mar 14 2004, 02:27 AM
#1 cause: people are bunnyin hard on their brakes, i had stock rotors unwarped up until 90,000 miles. the only reason they went bad then was because the caliper locked and i had to replace everything. you people must drive like maniacs to warp them, seriously.

True, if you are nice to your brakes they will last alot better. But when I was doing 135k on the highway, and some efftard pulls out going 90 right infront of me, I had to slam those puppies, and they warped up right away. The rest of the drive home the car shook like mad when I applied the brakes. Got em machined, and they've been fine since then, but one bad incident can wreck them (which does mean they suck sh*t).

lol its fun to see that crap you do on your computer when lit pretty good.