Crash: Instructor braces himself with his feet on the dash.
05-26-2017, 11:43 AM
#151
WRONGLY ACCUSED!
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I have gotten into the habit of testing the brakes on the way out of the pits several times. I used to just blast out and hit the brakes in the first braking zone - no more!
05-26-2017, 12:11 PM
#153
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My coach is always telling me to do this mainly to reseat the pads in addition to the safety factor. Need to work more on this as well.
I have gotten into the habit of testing the brakes on the way out of the pits several times. I used to just blast out and hit the brakes in the first braking zone - no more!
I have gotten into the habit of testing the brakes on the way out of the pits several times. I used to just blast out and hit the brakes in the first braking zone - no more!
05-26-2017, 01:33 PM
#155
WRONGLY ACCUSED!
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05-26-2017, 03:12 PM
#157
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05-26-2017, 03:18 PM
#158
Rennlist Member
Here is the driver's post-mortem
http://jalopnik.com/bmw-driver-survi...ses-1795500447
http://www.r3vlimited.com/board/showthread.php?t=406490
http://jalopnik.com/bmw-driver-survi...ses-1795500447
http://www.r3vlimited.com/board/showthread.php?t=406490
question is, if it wasnt a blown line, it was pad knock back, which means brakes were fine just had a "situation" .
From reading through the r3vlimited thread apparently the car had a modified/replaced master cylinder as part of the S52 swap. For those not familiar with BMWs, the S52 is the stock motor in an E36 M3. This guy's car was an E30, a generation older. So he swapped more than just the power train.
It wouldn't surprise me if something failed within the modified parts. One thing nice about stock is you stand on the shoulders of the product testing and engineering of the manufacturer. When things get modded, some or all of that is out the window and the likelihood of a failure increases even if the mod is done well.
-Mike
It wouldn't surprise me if something failed within the modified parts. One thing nice about stock is you stand on the shoulders of the product testing and engineering of the manufacturer. When things get modded, some or all of that is out the window and the likelihood of a failure increases even if the mod is done well.
-Mike
"Thirty minutes into the session without any warning the brakes were gone and I had no pedal pressure as I entered the braking zone into turn 8."
Boiled brake fluid? WG can be tough on brakes.
I recently had a student with a heavily modded WRX, 450 hp, stripped out, full cage, harnesses, coilovers, track pads - and street brake fluid.
Boiled brake fluid? WG can be tough on brakes.
I recently had a student with a heavily modded WRX, 450 hp, stripped out, full cage, harnesses, coilovers, track pads - and street brake fluid.
blown line or pad knock back. sometimes that can be caused by a hurt front hub. maybe the reason that the car wiggled on brake application.
I do that left foot double tap as well. After an instance at Summit Point years ago in my dads car. Braked for turn one pedal went soft (car was getting double duty in August). Pumped it while coming down through the gears while keeping the car straight as long as I could and took the corner around the outside. Since then, I always give the brake pedal a light tap before I get to the end of a long straight.
As far as the incident in question, sounded to me like he pushed and held the clutch in and disengaged the drive train. Did that ONCE at my first DE. Instructor smacked my thigh (1997 so not everyone had a communicator) and told me always keep the drive train working for you and never coast and the only time the clutch should be in is during a gear change, or if it's a both feet in moment.
As far as the incident in question, sounded to me like he pushed and held the clutch in and disengaged the drive train. Did that ONCE at my first DE. Instructor smacked my thigh (1997 so not everyone had a communicator) and told me always keep the drive train working for you and never coast and the only time the clutch should be in is during a gear change, or if it's a both feet in moment.
again, ive posted my video of my brake line burst at laguna at 120+mph. i had enough engine braking forces to save the car AND actually make the turn at turn 2.
since then, i also left foot tap the brake pedal on most alll long straights, and sometimes on the most critical turn approaches where even a soft pedal can be dangerous.
yep!
05-26-2017, 03:35 PM
#159
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In the BMW forum, he said:
So, we are left with no pedal , but after the fact, he still feels pressure generated on the pedal. sounds like pad knock back. could have had a smalll leak too.....that with repeated braking activity wouldnt show itself.
hard to speculate.
downshifting can safe your car regardless. that's why i stressed it in the other thread that i was argued with so much..... trust me.. ive been there it works and there is NO downside if you do it correctly. even the owner was talking about car instability chances if he pulled the ebrake or downshifted. when you are braking straight, this is NOT an issue. I've done ebrakes at 100mph, its not a problem..... downshifting when done correctly, is not a problem. you dont just toss it in gear and release the clutch, you blip the engine and release..wait, blip again and shift/release. the forces on the wheels are just engine compression forces. ive measured these forces on the dyno and they are substantial and go up with every shift. in these situations we are only talking about a 3rd and 2nd gear shift anyway. two simple shifts can save your life.. i would encourage all racers to practice this every race /DE weekend.
Mk
__________________
"I had a UUC BBK
New Rotors Front
New DTC 60 Pads Front
New Rotors Rear
New DTC 70 Rear Pads
Stainless Steal Brake Lines
and Fresh RBF600
After being under the car for the first time last night I couldn't find any blown lines or ruptures. I did notice the pass caliper looked like it may have a had a small amount of fluid leak from it. Brake res was still in the middle with fresh fluid. So either I blew a piston or maybe something internal like mc."
New Rotors Front
New DTC 60 Pads Front
New Rotors Rear
New DTC 70 Rear Pads
Stainless Steal Brake Lines
and Fresh RBF600
After being under the car for the first time last night I couldn't find any blown lines or ruptures. I did notice the pass caliper looked like it may have a had a small amount of fluid leak from it. Brake res was still in the middle with fresh fluid. So either I blew a piston or maybe something internal like mc."
hard to speculate.
downshifting can safe your car regardless. that's why i stressed it in the other thread that i was argued with so much..... trust me.. ive been there it works and there is NO downside if you do it correctly. even the owner was talking about car instability chances if he pulled the ebrake or downshifted. when you are braking straight, this is NOT an issue. I've done ebrakes at 100mph, its not a problem..... downshifting when done correctly, is not a problem. you dont just toss it in gear and release the clutch, you blip the engine and release..wait, blip again and shift/release. the forces on the wheels are just engine compression forces. ive measured these forces on the dyno and they are substantial and go up with every shift. in these situations we are only talking about a 3rd and 2nd gear shift anyway. two simple shifts can save your life.. i would encourage all racers to practice this every race /DE weekend.
Mk
__________________
05-26-2017, 09:17 PM
#160
Racer
05-26-2017, 09:56 PM
#161
Rennlist Member
I have 5 track days done.
Can you point out where in this initial video, that the "tap,tap" should be done, coming out toe of the boot and approaching the heel.
I am thinking maybe just as you have tracked out of the toe, or is that wrong?
David
Can you point out where in this initial video, that the "tap,tap" should be done, coming out toe of the boot and approaching the heel.
I am thinking maybe just as you have tracked out of the toe, or is that wrong?
David
05-26-2017, 10:23 PM
#162
Rennlist Member
Whenever your wheels are straight and you're at WOT you can do it. Especially on straights after you've made judicious use of curbing. Just bring the left foot over and gently feel for the pads getting to the rotors.
05-26-2017, 10:33 PM
#163
Rennlist Member
I can't wait to go to another DE.
It seems like each time I do a DE, the anticipation for the next time is more intense.
it's a good thing I am on a limited budget, if not I would be at a track every weekend
05-26-2017, 10:33 PM
#164
Drifting
Is this pad knock more relevant with hard/race suspension? I've yet to have the issue, but also trying to develop habit or tapping the brakes...and checking gauges...and tightening belts...damn lots to do on the straights, good thing my car is slow.