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      06-27-2013, 09:34 PM   #45
trackjunky
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Originally Posted by gtMc View Post
A friend of mine just sent me this video link, an E46 with a heel-toe cam installed, this is the clearest video I have seen that demonstrates it. I dont know the driver, but the track is Lightning@ NJMP, and he is a friend of a friend I guess. And he passes a red ///M coupe early on... Enjoy.

i'm the driver in the video. I remember your red ///M coupe actually. That was a fun weekend.
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      06-29-2013, 03:29 PM   #46
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Here's a recent trip to a very wet Watkins Glen. Shows a different way to heel-toe. I also do this on regular street driving, not often but sometimes. I just needed to blip the throttle very slightly and this gives better control over the blip. I don't particularly like braking with touching half of the brake pedal on the track so I do most of my braking on the full pedal and then slowly slide my foot over the brake pedal to the right (while still finishing the braking) and get it ready to do the blip.

Hope this paints a clearer picture.

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      10-04-2016, 07:17 AM   #47
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This is my first post. I want to start with a big "thank you!" to 3002 tii for sharing his insights on H/T and several other topics and for directing me to this thread. Also, many thanks to everyone who's contributed to this thread. It's been super helpful!

I drive an '07 Z4 Coupe 3.0si (6 spd manual) in silver. I'm heading to Summit Point Motorsport Park this weekend for my 7th HPDE with BMW CCA. I've been struggling with H/T on the track and think the posts in this thread are really going to help.

I realize this post is a few years old. But, wanted all who have contributed to know it's still read and appreciated.
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      10-12-2016, 01:00 PM   #48
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I find that the BMW's are one of the easiest cars to heel toe in, because of the gas pedal being so long. I've driven subaru's, honda's, acura's, and toyota's, and those gas pedals are hard to reach without the full inward twist of my leg/ankle to blip the throttle. I still use the heel to blip in any car.
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      10-12-2016, 08:40 PM   #49
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I'd love to be able to actually use my heel to heel/toe, but I have feet like snow shoes (EE width). I stuff my feet into a pair of Van's skate boarder shoes to get enough room in the Z4 pedal box and still have to use the side of the foot method.
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      10-31-2016, 12:03 PM   #50
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^ I use the same type of shoe and have to use the side of my foot as well because the length of my feet it's a lot more difficult to make good contact with your heel with long feet.
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      04-02-2017, 11:09 AM   #51
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New to Heel/Toe

I've been driving stick my whole life with various sports/fast cars. Never raced, never found a need to heel-toe. I found this post VERY informative. I have read a few things on heel-toe and on a track, where every tenth of a second counts and speeds are much faster than on a street, I can see I need to start practicing this more often on the street. I have tried rev-matching and found it difficult. I test drove a 2014 370 Z, with auto rev-matching. I felt like it was like training wheels for stick shift driving and didn't like it. While doing 55 mph on the test drive, with a young salesman who did not know how to drive stick, I wound up third, dropped the clutch and slipped it into second. The dual clutch rev-matcher shot the tach up to near red-line. Kid looked at me as the motor was screaming, I was just like " don't worry, I'm not going to let the clutch out, I just wanted to see how this worked " I then turned it off.
I'm sticking to autocross for now. No shifting needed. I plan on getting to Sebring down the road. I'm loving my 2006 Z4MR. I see that THE HACK had a lot of great advice on a post named "Autocross with a Z4MR- tips". Many good ones on here as well.
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      03-08-2018, 05:38 PM   #52
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I'm battling similar issue, and after driving in various other cars, I noticed the Z4 brake pedal travels a lot more than others before it grabs. We seem to have long travel progressive pedal.

I've raised my brake pedal almost 1/2 inch with padding to get around it. That is the only way I've found to give me just the right height for heal-toe on aggressive braking.

Otherwise, I would brake heavily and the right side of my foot would inadvertently start applying gas.

Anyone else notice Z4s have a long brake pedal travel (even with BBK??). Anyone find a way to reduce travel?
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      03-08-2018, 07:21 PM   #53
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Quote:
Originally Posted by dre99gsx View Post
I'm battling similar issue, and after driving in various other cars, I noticed the Z4 brake pedal travels a lot more than others before it grabs. We seem to have long travel progressive pedal.

I've raised my brake pedal almost 1/2 inch with padding to get around it. That is the only way I've found to give me just the right height for heal-toe on aggressive braking.

Otherwise, I would brake heavily and the right side of my foot would inadvertently start applying gas.

Anyone else notice Z4s have a long brake pedal travel (even with BBK??). Anyone find a way to reduce travel?
I've had this on and off with my 3.0si. Two causes so far were pad knock back due to a set of DS2500 pads in the front calipers that wouldn't stay clipped into the pocket in the caliper piston, and a set of AutoZone anti-rattle springs that were too thick and contacted the back of the brake pad pushing against the rotor. Rotors where the plane of the braking surface isn't on the same plane as the surface that mates with the hub can also cause knock back of the pads. Debris trapped between the rotor and the hub can also cause it.
If you've changed pads on your Z4 you've probably seen that it takes 3-4 full strokes of the brake pedal to move the pads into contact with the rotor. It doesn't take much knock back to cause a need for about 1/2 stroke to get the pads back in contact. The knock back can come from either the front calipers, the rear calipers or both.
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      03-08-2018, 07:30 PM   #54
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Quote:
Originally Posted by dc_wright View Post
I've had this on and off with my 3.0si. Two causes so far were pad knock back due to a set of DS2500 pads in the front calipers that wouldn't stay clipped into the pocket in the caliper piston, and a set of AutoZone anti-rattle springs that were too thick and contacted the back of the brake pad pushing against the rotor. Rotors where the plane of the braking surface isn't on the same plane as the surface that mates with the hub can also cause knock back of the pads. Debris trapped between the rotor and the hub can also cause it.
If you've changed pads on your Z4 you've probably seen that it takes 3-4 full strokes of the brake pedal to move the pads into contact with the rotor. It doesn't take much knock back to cause a need for about 1/2 stroke to get the pads back in contact. The knock back can come from either the front calipers, the rear calipers or both.
I saw your post regarding that. I'm on those 335i front calipers which don't use those clips but a different style. Yes they were autozone clips as well (but PFC race pads). And, I've switched to 135i rear calipers which are different piston setup. Yes, slightly larger piston than stock.

I looked at the front clips and other than ordering new OEM clips for comparison, not sure they would cause this same issue.

Can anyone here who's gone to BBK confirm that brake pedal travel decreased for the same amount of pressure?
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      03-09-2018, 07:52 AM   #55
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Quote:
Originally Posted by dre99gsx View Post
I saw your post regarding that. I'm on those 335i front calipers which don't use those clips but a different style. Yes they were autozone clips as well (but PFC race pads). And, I've switched to 135i rear calipers which are different piston setup. Yes, slightly larger piston than stock.

I looked at the front clips and other than ordering new OEM clips for comparison, not sure they would cause this same issue.

Can anyone here who's gone to BBK confirm that brake pedal travel decreased for the same amount of pressure?
Honestly don’t recall noticeable difference in pedal travel when I had my ST40 kit
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      03-09-2018, 01:31 PM   #56
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Quote:
Originally Posted by dre99gsx View Post
I'm battling similar issue, and after driving in various other cars, I noticed the Z4 brake pedal travels a lot more than others before it grabs. We seem to have long travel progressive pedal.

I've raised my brake pedal almost 1/2 inch with padding to get around it. That is the only way I've found to give me just the right height for heal-toe on aggressive braking.

Otherwise, I would brake heavily and the right side of my foot would inadvertently start applying gas.

Anyone else notice Z4s have a long brake pedal travel (even with BBK??). Anyone find a way to reduce travel?
I don't notice that with my front and rear BBK.
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      03-09-2018, 04:10 PM   #57
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Quote:
Originally Posted by angelr View Post
I don't notice that with my front and rear BBK.
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Never an issue with Stoptech 6/4
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      03-09-2018, 05:15 PM   #58
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In my experience...

BMW pedal travel is longer than Porsche pedal travel, but shorter than Asian imports (I've had experience with Nissan, Subaru, and Hyundai on track) with better modulation on stock systems. Modified systems, all bets are off. The WORST is 'Mercan cars, unless they're equipped with large, multi-piston fixed calipers (Challenger SRT-8) from the factory.

If you've got excessive pedal travel before brakes will engage, it's likely there's air trapped in the line or you've got mis-matching slave cylinder area to master cylinder ratio. What I've also noticed, on the MZ4 especially, it MUST share the same brake master cylinder design as the E36 M3, because it's got that same issue that once you get air in the lines, and you crack it open to bleed/flush, you will NEVER get the same feel back. I don't know what it is. Never had that problem on the E46, didn't have that problem with the Z4 3.0i when I tracked it heavily...The MZ4 Coupe, after the first bleed, didn't quite feel the same with the brake pedal engagement.

With the RacingBrake 4 piston front, 2 piston rear fixed calipers though, it's got that quick engagement back. At least compared to what else I drive regularly now in the garage (the 335D and the Fiat 500e). Can't really compare it to the i3 because I rarely use the brake pedal on the i3.
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      03-09-2018, 09:24 PM   #59
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Well how about this:

I checked my brake pedal, seems that I have 3mm of pedal travel before I feel the brake being applied. Seems to be a tolerance in there, but not from the pedal to rod attachment. Perhaps some play inside the boot towards the brake booster, and something tells me some amount of play is required...

Anyone else have this amount of play?
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      03-09-2018, 10:21 PM   #60
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Quote:
Originally Posted by dre99gsx View Post
Well how about this:

I checked my brake pedal, seems that I have 3mm of pedal travel before I feel the brake being applied. Seems to be a tolerance in there, but not from the pedal to rod attachment. Perhaps some play inside the boot towards the brake booster, and something tells me some amount of play is required...

Anyone else have this amount of play?
Come to Lime Rock in April and we can compare setups
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      03-09-2018, 10:28 PM   #61
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Haha.. Lime Rock in April eh? That's a long trip that I need to do some weekend!
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      03-12-2018, 08:39 PM   #62
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Quote:
Originally Posted by dre99gsx View Post
I saw your post regarding that. I'm on those 335i front calipers which don't use those clips but a different style. Yes they were autozone clips as well (but PFC race pads). And, I've switched to 135i rear calipers which are different piston setup. Yes, slightly larger piston than stock.

I looked at the front clips and other than ordering new OEM clips for comparison, not sure they would cause this same issue.

Can anyone here who's gone to BBK confirm that brake pedal travel decreased for the same amount of pressure?
To check for knock back you need to get set up to jack up the car and pull the wheels, then drive the car making some left and right turns to get the full impact of any bearing play WITHOUT touching the brake pedal. Only use the e brake to get the car to where you're set up, then jack it up, pull the wheels, and look at the gap between the pads and the rotors. It should be near zero, like you can barely slip a sheet of paper into the gap.
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