Brake Myths

I'm calling BS on number two. As someone who used to machine the rotors, I can say, unequivocally, it is entirely possible for rotors to warp. I've personally machined my own rotors flat, only to see them warped again. Heat cycling cast iron can and does result in movement as the stresses are induced and/or relieved. There is a reason the OEMs have a tolerance for the runout of a brake rotor...

As someone who designed a performance brake system based on Carroll Smith's design tutorials, in a small open-wheeled Formula car, I assure you there are advantages to cross-drilling, namely that it increases the surface area and reduces the weight over a solid rotor. Anywhere there is a polar moment of inertia gain to be had, it's absolutely worth finding it for acceleration and braking performance.

a feathered tire... has what... to do with brakes or braking...????:h

Feathered a fairly new set of Michelin ATX-MS LT265/75R16E's on 16x10 alloys

rims are a little wide for tire size ...no? 7" min 8" max width??

Ben, not sure why you think the Praise Dyno rotors are "all that" if they check like that....maybe it's the change in the NBS platform, but I have not found anything that will beat the OEM pads and rotors. I don't take my 2500 burb to the track and don't see ant benefit to slotted or drilled rotors. I used slotted rotors on my 94 SHO because Ford OEM brakes were crap.

I have to say its true, if you buy GM you get two legendary design capabilities, brakes and heat LOL/.

Don,

OEM rotors checked too and mainly due to Praise Dyno. Stock pads, Performance Friction
Carbon and NAPA Metalic HD. The Praise Dyno friction material is 'all that'
because they have such high braking power

Here is what my OEM rotors looked like just before one of those cracks went
clean through
heatcheck

The previous picture is of second set of rotors and checked from
buddies proto-type and Praise Dyno

My 2 seater always heat checked it's rotors. Ditto old MGB.

Don't drive the sedans, mini van nor Silverado like that, so their rotors don't
heat check

But few people drive their TV's like I do. Some do with their sports cars.

Current set of Bridgestone Dueler Revo AT's are also 'slightly' feathered from
braking testing current proto-types from buddy. Only because it's my weekender
and love getting on it...even going to the grocery store. These took many weekends
while the Michelin LTX-MS's feathered on that 80 mile round trip to volleyball

Just put a set of MonoMax Shocks on the Silverado and it behaves much better.
Even with a load of wood pellets (about 2.4K lbs). Since it's a 1980 and old,
don't push it as hard as used to.

Definition of 'heat checking' below

heat check
{?h?t ‚chek}
(metallurgy)
Parallel surface cracks forming a pattern on the surface of a metal as a result of thermal fatigue.


I get my brakes that hot and is very common on tracked vehicles with
friction material high enough to rip apart the rotor surface

Why few have seen this, except for racers, because their friction
material is not of this performance level. They will fade before they
ever develop this level of friction...to get that hot and develop
enough force to rip apart the rotor surface

A bit disjointed...on the phone while writing the above

OEM can NOT develop the kinds of heat and braking forces to heat check.

They will get so hot and out-gas (fade) approaching the temp levels performance
pads will just be getting to their 'good' temp range and highest friction...to
continue to raise in temp and raising friction levels.

That is why OEM level (our TVs) can NOT (generally) cause heat checking on their
rotors

This is why 'modulation' so important.

OEM will just grab to initiate ABS...while performance level can be modulated
just before ABS initiate point

Why tires will feather from folding over the tread blocks...even high way
tread. As they too have tread blocks or edges that fold over to feather while
braking that hard

Heat checked rotors and feathered tires are common over at mh boy racer forums

WOW you put that burb through its paces all right!!

Why tires will feather from folding over the tread blocks...even high way
tread. As they too have tread blocks or edges that fold over to feather while
braking that hard

gee-buz Ben... "feathering" of the tires is due to improper toe-in, and/or worn out bushings causing wheel alignment to shift as the vehicle moves down the road, nothing to do with braking.

What your showing and talking about is called "CUPPING" or "SCALLOPING", which is normal wear for hard acceleration and braking.

Too bad ole Ben has me blocked.... sad because there are so many here that believe everything he says, sure talks a good talk, but I gotta call BS when I see it... like how hes developing a programmable control system for "his" gas compressor... sorry Ben but those panels have been around for 30+ years!

gijoecam wrote:
I'm calling BS on number two. As someone who used to machine the rotors, I can say, unequivocally, it is entirely possible for rotors to warp. I've personally machined my own rotors flat, only to see them warped again. Heat cycling cast iron can and does result in movement as the stresses are induced and/or relieved. There is a reason the OEMs have a tolerance for the runout of a brake rotor....

I agree completely. Have measured runout hundreds of times with a dial indicator. It is often pretty obvious when a rotor is warped.

BenK wrote:

Feathered a fairly new set of Michelin ATX-MS LT265/75R16E's on 16x10 alloys

I would be perfectly happy if my Michelins were feathered, because that is the only way the tread blocks will wear out before the sidewalls crack.

Sorry, off topic irrelevant comment.