JDKane527

iTrader: (10)

Cars won't benefit from BBKs if they don't have wider tires, and vice versa, which I agree with. Just isn't all the information on it, and you have to look at more advanced physics to see how these all work together. And for ABS engagement, these rotors probably engage ABS faster than regular rotors, the fraction of a second faster which you won't notice on regular street driving.

fknISC808

iTrader: (1)

that is great info Kurtz and stonefan52, guys like you are the reason im on this board. Although, physics is like taxes to me, i always like a good lesson.

Kurtz

iTrader: (1)

Well, not specifically wider tires... tires with a much higher traction limit... (higher than any tire you'd run on the street, by quite a lot).

Hence for street use any brake upgrade will be entirely for the look/feel, not the reduced stopping distance.

If you want shorter stops on the street, get stickier tires.



On a track, where you can run stupid big slicks, you can probably get tires on there that exceed the ability of the OEM brakes to engage ABS (though I'm unsure if you can do so without tubbing out the back or anything too) but 99.99% of IS owners won't ever do any of that.

But if you did, at THAT point, then bigger brakes would help you stop... right up until you reached the limit of THOSE tires.


Because again, the tires are what stop the car. They are, ultimately, 100% of the time, the limiting factor in braking distance...

Or as Pulp Friction puts it-

JDKane527

iTrader: (10)

^^^

A1Lexis

iTrader: (6)

Kurtz always has the best explanations on brakes, tires and suspension parts for our cars. One can def. learn alot by reading his posts

Dunkin1222

So did he ever mention what kind of pads or rotors he's using?

jtamulis

iTrader: (1)

Kurtz? He's his using his factory IS350 pads/rotors. (I think the pads were changed do to the brake dust recall if I remember right).

Kurtz

iTrader: (1)

Yup... the OEM low dust front pads, original rears, and original rotors. Since I don't drive the car on a circle track or rally race it or anything, and don't plan to, there's no reason to use anything more expensive.

mikez

I was at the Porsche dealer today, with exception to the PCCB, none of the Porsche brakes are drilled nor crossed anymore.

juice14

Love the pulp friction article. Id say 99% of people think the brakes are what stop the car.

question for Kurtz: I went to the track with stock brakes and experienced brake fade. then, on the same track with the same tires and similar weather I went with drilled rotors and ceramic pads and experienced ALOT less brake fade (today), does that diference in brake fade come from the pads only? or the combinaton of the drilled rotors and the brake pads?

jtamulis

iTrader: (1)

It would be the pads, yes. And also did you change the fluid out when the stuff was replaced? That makes a difference too.

Jeff

Kurtz

iTrader: (1)

Assuming the drilled rotors were of the same size as the OEM ones yeah it was the pads.

Rotors are heat sinks... drilled rotors have less mass, and thus can hold less heat.

More significant though is that the drilled rotors tend to not only eat pads faster than blanks, they crack pretty easily when abused at all... a quick search ought find you the pic Lance posted of his IS-F rotors (which are factory drilled) and the cracks in them from one hard trip to the track.

Drilled rotors will deglaze the pads and keep em clean on the track... but slotted will do that just as well without the significant risk of heat risers and stress cracks that drilled rotors come with.

There's a reason even the major brake makers (Stoptech for example) tell you for real track applications they recommend slotted, not drilled.

lobuxracer

iTrader: (2)

Not just the pads, but your skill level as well. When you're using the brakes briefly but very hard and giving them time to recover before you use them again, you'll see reduced fade. One of the hardest lessons to learn is how to wait until the last moment, then brake very hard (but not too much), and get off the brakes to allow them to cool. I found with the F the faster I went, the less braking issues I had because I was using the brakes better as I went faster.

I also found that drilled rotors (even Brembo!) crack no matter what you do.

juice14

Thanks for the info kurtz and lobux. Im kind of glad this track is not too hard on the brakes, maybe on another track they would have cracked already. Ive noticed the skill level part is very important. I went this year to the track several times and before that I had never done a track day. I think ive improved my skills as well so maybe that one of the reasons I have less brake fade. I went from doing 1:43 around the track my first time (toyo T1r tires), and my best time has improved to 1:36 (with michelin ps2) although the tires have made a difference I think braking latter has made a difference as well. Now im gonna get the frontsway bar and maybe ill be able to tell a difference on the track with the same tires.

Also the first time I went with stock pads, the Ceramic pads are much better for the track.

ALLCHILL

hey what kind of ceramic pads are you running? im planning on road racing again come spring. thanks in advance