Myth - racing gearboxes are never in two gears at once. That would spell instant 'box explosion.

Quote from tristancliffe :

Myth - racing gearboxes are never in two gears at once. That would spell instant 'box explosion.

So the holy grail of the seamless-shift gearbox is to replace the dog rings with something else – something that selects the next gear before the current one is disengaged:

technical-details-of-a-formula-1-car.htm

... 2nd gear overdrives first gear ...

http://en.wikipedia.org/wiki/Zeroshift

http://auto.howstuffworks.com/dual-clutch-transmission.htm

Quote from JeffR :

Racing transmissions like the Hewland use dog ring type setups, which don't need synchros. During a shift on a racing transmission, there's a period in time where both gears are engaged at the same time, but it's not an issue, since thost transmissions aren't meant to last as long or be as smooth as a passenger car transmission:

A dog box spends time in neutral before the next gear, just like all constant mesh transmissions. A dog ring cannot be in contact with both gears at once. That would rip the internals like a nuclear explosion.

I'm assuming, of course, by "racing transmissions" you mean face dog gearboxes.

Here's a dog type sequential six. Have a look for yourself:

Quote from JeffR :

Racing transmissions like the Hewland use dog ring type setups ... a period in time where both gears are engaged at the same time

Quote from MadCat360 :

A dog box spends time in neutral before the next gear, just like all constant mesh transmissions. A dog ring cannot be in contact with both gears at once.

Sorrty, I left out a paragraph. Hewland sequential shift trannies can be shifted without the clutch, and depending on the electronics, shifted without clutch or without lifting. Another common brand of no-lift sequential shifter is made by XTRAC.

A racing form of DCT (dual clutch transmission) has dual clutches with even and odd gears running on different shafts, allowing for overlapped gear engagement during sequential shifts. DCT's are banned in Formula 1 racing, but the new "seamless shift" gearboxes are allowed, and there is still some overlap during a gear shift, combined with computerized control of clutch and fuel injection to smooth out the jerk on the drive train, while maintaining positive torque and power to the wheels.

SSG part 1.htm

SSG part 2.htm

Quote from JeffR :

Sorrty, I left out a paragraph. Hewland sequential shift trannies can be shifted without the clutch, and depending on the electronics, shifted without clutch or without lifting. Another common brand of no-lift sequential shifter is made by XTRAC.

A racing form of DCT (dual clutch transmission) has dual clutches with even and odd gears running on different shafts, allowing for overlapped gear engagement during sequential shifts. DCT's are banned in Formula 1 racing, but the new "seamless shift" gearboxes are allowed, and there is still some overlap during a gear shift, combined with computerized control of clutch and fuel injection to smooth out the jerk on the drive train, while maintaining positive torque and power to the wheels.

SSG part 1.htm

SSG part 2.htm

Ah, I don't know anything about SSG so I didn't realize.

Quote from tristancliffe :

Nah, most cars allow heel and toe, you just need man-sized feet

I've only got size 7 and a half feet and I've never driven a car I couldn't heel-toe.

Quote from Keling :

Girlfriend .............


Strange. How can a person be killed by 12V ?

The airbag on the Miata only needs 5v to discharge, the guy was in an odd position, sitting on the door frame, but the guy's head was against the steering wheel, while he was feeling around under the dashboard. I can't even imagine how bad that must have been. I just took both of mine out after I heard about it, I don't even want mazda to replace it, free or not, in this case I feel their safety measures are more dangerous to have, then to not have.




speaking of which, the I found the actual complete footage of the heel-to-toe scene I put in my "through the fog" youtube video. I shot the footage also on that same section of road, it's just a much better view, more detailed then the other one, since it's the complete footage, so you get a better sense of it.

http://www.youtube.com/watch?v=G41qs6rXLUc

Quote from Gentlefoot :

I've only got size 7 and a half feet and I've never driven a car I couldn't heel-toe.

ya but you got a very gentle heel-toe foot

Pedal extensions help, or you can just get some Swan-necks and bend the throttle pedal over to the left a bit, wouldn't reccomend that though.

lol I used to think faster was better, until I was taught to be smooth on the pedals/steering wheel input. I used to oversteer like crazy, before I knew how to let the car roll using light input on the pedals / steering wheel, only turn as much as you need to get the car where you want it to be, basically, and it will get there faster, instead of rushing which always leads to mistakes or jerky movements.

Quote from Gentlefoot :

I adjusted my rear brakes last week. Where the shoes had worn down there was a massive gap between them and the drum. It meant I had a lot of peddle travel. Brakes feel much better now but the different biting point for the brakes has screwed my heel-toe completely. Nearly went through the windscreen the first time I tried it.

Gonna take a few weeks to get used to.

I don't see how improving the back brakes can make your braking pro-sufficient enough to make you go through the windscreen, brake bias on road cars favours the front end and if your bias was all the way on the back, then you would just spin out.

Quote from Pablo Donoso :

speaking of which, the I found the actual complete footage of the heel-to-toe scene I put in my "through the fog" youtube video. I shot the footage also on that same section of road, it's just a much better view, more detailed then the other one, since it's the complete footage, so you get a better sense of it.

http://www.youtube.com/watch?v=G41qs6rXLUc

I never liked the traditional way of doing it, with the side of the foot. Skip Barber taught me to cover both pedals with each half of my foot and to just turn my knee over to blip. Kinda hard to do in a road car with wide pedals though.

But watch how one of my other instructors does it, from Jim Russell:

http://www.youtube.com/watch?v ... jUCIA&feature=related

He blips with his toes... never seen that done. Looks smooth.

He's big on left-foot braking, too.

brake with the left foot and then the right foot takes over... that's sick.

Quote from Bandit77 :

brake with the left foot and then the right foot takes over... that's sick.

i might do that, but idk, whatever i do i do, i am paying attention to driving.

Quote from BlueFlame :

I don't see how improving the back brakes can make your braking pro-sufficient enough to make you go through the windscreen, brake bias on road cars favours the front end and if your bias was all the way on the back, then you would just spin out.

It wasn't the increase in rear brake strength. As I said, it was the change in position of the biting point of the brake pedal. Whereas before the pedal would travel a good inch and a half before biting now it only travels about half an inch before biting.

This meant that the first time I heel-toed as I blipped the throttle I hit the brakes much harder than I wanted to. I've got used to the change in biting point now and back to heel-toeing as normal.

Quote from MadCat360 :

I never liked the traditional way of doing it, with the side of the foot. Skip Barber taught me to cover both pedals with each half of my foot and to just turn my knee over to blip. Kinda hard to do in a road car with wide pedals though.

But watch how one of my other instructors does it, from Jim Russell:

http://www.youtube.com/watch?v ... jUCIA&feature=related

He blips with his toes... never seen that done. Looks smooth.

He's big on left-foot braking, too.

Wow, that is more like the original "heal toe" where they did brake with their heal. I can see that he is using the ball of his foot and pivoting to blip the throttle though so he isn't really using his heal. Cool shot. I'm going to have to give it a try that way since I always run into trouble with my heal hitting the floor when I try to blip the throttle with my heal.

I also had never seen somebody switch the foot they are braking with mid-corner like that. I can understand though, using the throttle to balance the car along with the brake would be advantageous in that car.

Quote from MadCat360 :

But watch how one of my other instructors does it, from Jim Russell: http://www.youtube.com/watch? ... jUCIA&feature=related

lol Rick, white dude kinda like capt. picard haircut? If that's the same guy, I had him as an instructor too back in '02 xD. John is the b0m, he wears glasses, but you wouldn't think he could drive. He opens up a can 'o who0o0p ass on the track though.

Yeah, my side kick was just the most comfortable and more importantly, most consistent on both blips and braking. lol

Quote from Hallen :

Wow, that is more like the original "heal toe" where they did brake with their heal. I can see that he is using the ball of his foot and pivoting to blip the throttle though so he isn't really using his heal. Cool shot. I'm going to have to give it a try that way since I always run into trouble with my heal hitting the floor when I try to blip the throttle with my heal.

I also had never seen somebody switch the foot they are braking with mid-corner like that. I can understand though, using the throttle to balance the car along with the brake would be advantageous in that car.

Quote from Pablo Donoso :

lol Rick, white dude kinda like capt. picard haircut? If that's the same guy, I had him as an instructor too back in '02 xD. John is the b0m, he wears glasses, but you wouldn't think he could drive. He opens up a can 'o who0o0p ass on the track though.

Yeah, my side kick was just the most comfortable and more importantly, most consistent on both blips and braking. lol

Yep. Ric has a lot of interesting ideas on braking. Pablo, did he ever give you the "thirds braking" rundown? I remember that very well from my first day. He's brilliant.

Quote from MadCat360 :

Yep. Ric has a lot of interesting ideas on braking. Pablo, did he ever give you the "thirds braking" rundown? I remember that very well from my first day. He's brilliant.

care to explain thirds braking thing?

Quote from logitekg25 :

care to explain thirds braking thing?

Ric's theory is that a full threshold stop from the beginning of the braking zone all the way to turn in will cause the driver to over-slow the corner. To combat this, he divides his braking zones into thirds.

We use threshold pressure for the first two thirds, then bleed off the brake during the last third so that before the turn-in point our tires are no longer making that nice chirping threshold noise. This will allow our brains to process the speed faster and get a more accurate feel for how fast exactly to enter the corner, rather than focusing wholly on slowing down even at the turn in point. It's a technique to supplement consistency and in so doing increasing our speed over the course of a race.

I don't use the thirds bit, but I make sure that I'm bleeding off the brake just before the turn in point. Works good for me, rather than holding threshold all the way to turn in.

Quote from MadCat360 :

Ric's theory is that a full threshold stop from the beginning of the braking zone all the way to turn in will cause the driver to over-slow the corner. To combat this, he divides his braking zones into thirds.

We use threshold pressure for the first two thirds, then bleed off the brake during the last third so that before the turn-in point our tires are no longer making that nice chirping threshold noise. This will allow our brains to process the speed faster and get a more accurate feel for how fast exactly to enter the corner, rather than focusing wholly on slowing down even at the turn in point. It's a technique to supplement consistency and in so doing increasing our speed over the course of a race.

I don't use the thirds bit, but I make sure that I'm bleeding off the brake just before the turn in point. Works good for me, rather than holding threshold all the way to turn in.

so basically trail braking

Quote from logitekg25 :

so basically trail braking

Yes, but trailing the brake before the turn in point. Most racers are already adding steering while threshold braking. With thirds braking, you're bleeding off the brake a good 30 or 40 feet before the turn in. Just to ease the effort of slowing down to allow your brain to focus on rolling speed rather than utter stoppage. Using thirds braking I'm easily carrying in a good half a mile an hour more into the corners, sometimes more, especially on new corners.

where can i find this guy?

Quote from logitekg25 :

where can i find this guy?

You can hire Ric to be your personal coach for any event. You could also come out to California and take a Jim Russell class, but no guarantee that you'll meet Ric.

damn im in the boston area