Brake Dive

[Captain_Stangin']

You're talking about heel/toe braking right? I gotta say I have some difficulty with that, my timing is off....I often downshift a little too early, without letting the brakes slow down the car enough. This results in a quick bark from the rear tires, as I lock them from a poor rev match.

I have to discipline myself into waiting a little bit longer before dropping a gear, sometimes the rev match is perfectly smooth....usually not though.

 

[Cone Sweeper]

LOL I had the same problem until I had a friend drive with me at Sebring who's been racing for 20+ and with mustangs forever it seems. But he kept asking if i was showing off with the heel toe action and I thought it was normal but seeing sometime it's a bit harder in high speed down shifts ( like 4th to 2nd ) becomes a pain if mess up .. braking early and all sorts..
Though it is a bit rough on the clutch if you do this letting the rpm's jump more then 1500 or so does a little more wear on it.. but I started down shifting while braking without rev matching. Kind of watching the rpm range with the braking and down shifting. It's not tap the brakes and downshift.. but it's while braking and down shifting. The car slow down 10x faster and was much easier to control.. less things to think about ( i.e. heel towing and worrying about braking too early or too late.. )

But the braking while downshifting became much easier.. and i found it was much faster. Running with those who were heel toeing I found myself being able to push a little deeper into the braking zones and having more to push out of the corners which eventually helped with passing some people faster in straights..

 

[Cone Sweeper]

Might not be the best.. and it does have wear and tear.. but it does work sometimes when I can't heel toe..

 

[Philostang]

Hmmm...I found that when you practice it enough, you stop thinking about heel-toe downshifting and just do it as automatic as you would up-shift. When we all first started learning the clutch, it was ugly, but the rewards are far better than ignoring it and getting an automatic. Don't do that!

You definitely do not want to let that 1,500 rpm jump happen too early...nice way to over-rev the engine. That quick bark of the rear tires can become a horrific KA-BOOM if you just pulled your engine well past redline.

You might consider whether or not you want to change brake pads more often or the clutch more often. Your call.

I just got back from the Autobahn CC, and one of the major objectives was to test my braking. I was getting some truly horrific rear-end instability the last two times out that was making it impossible to really drive the car hard. Long story short, the culprit was a bad alignment. The rear of the car was not centered (though not far off, at only 1/8" off center), and the front was all jacked up. HUGE THANKS to SoundGuyDave for teaching me to string the car (it's actually fun). The car is now stopping extremely well (and turn-in has improved, thanks to a more suitable alignment), but I still get a bit more brake dive than I'd like. I chalk most of that up to r-comps and springs that are really not up to the task.

FWIW, I'm running a Stoptech 14" BBK up front with XP12 pads and stock calipers/rotors out back with XP10 pads. I'm going to change my rear LCA angle, and then see if I can get some temps taken of the rotors. Some folks have found great success with running the same pads on all 4 corners (I used to w/stock front calipers), so if temps seem to warrant it I may try that as well.

Best,
-j

 

[Cone Sweeper]

Oh I agree.. practice is like seat time in a car on the track, the more you work on it the easier it becomes. I found at times it came natural on the track then sometimes I fell into the " Oh shit, i pushed too hard and went too deep into the braking zone " and found braking and down shifting without kicking the revs up helped.. never had the bark of the rear tires and never saw huge jumps in rpms. I guess it's just doing it at the right time.

And btw, the string trick for checking the back is awesome

 

[Sleeper_08]

My rear axle is a little off center as well so that might be contributing to my "wiggle". Unfortunately getting it centered with a Watt's link is more of a challenge than just adjusting the length of the panhard bar!

 

[Captain_Stangin']

Adjusting my CHE phb is gonna suck. The chassis side lock nut is in that partially boxed area. Any tips making this as easy as possible? Or should I just yank the whole damn bar?

Oh, and what do you guys do about jacking up the car? I am planning to place the jackstands on the front control arms, and under the rear axle to simulate a level height....does this sound like proper reasoning?

 

[Sleeper_08]

We set my PHB, when I had one, by jacking the car up and putting ramps only under the rear wheels and leaving the front on the ground. Measurements from weighted strings hanging from the fender lips to the tires confirmed that the amunt of off center was the same as having all four wheels on the ground. Then you can adjust it to center.

 

[Captain_Stangin']

Duly noted Sleeper, thanks.