Double-Clutch Heel/Toeing
#16
I still think there is merit in learning how to DCHT even if I ultimately do not end up using it on the track or street. The main reason it is helping me now is that, with its smaller margin of error, it is forcing me to become more aware of my shifting. Remember, I am still very much in the grasshopper stage . . .
#17
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I like my syncros, and since the brass ones in most of our trans's seem to wear out pretty quickly with track use, I find double-clutch downshifting to be a cost-saving skill. And I have not ever felt the requirement to perform lighting quick down-shifts, unless you want to row down through the gears and have a very close ratio six speed, like in the cup cars. BTW they have steel syncros to handle that abuse.
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Larry Herman
2016 Ford Transit Connect Titanium LWB
2018 Tesla Model 3 - Electricity can be fun!
Retired Club Racer & National PCA Instructor
Past Flames:
1994 RS America Club Racer
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Larry Herman
2016 Ford Transit Connect Titanium LWB
2018 Tesla Model 3 - Electricity can be fun!
Retired Club Racer & National PCA Instructor
Past Flames:
1994 RS America Club Racer
2004 GT3 Track Car
1984 911 Carrera Club Racer
1974 914/4 2.0 Track Car
CLICK HERE to see some of my ancient racing videos.
#18
Hi Ted,
I also did the Bertil Roos school and I am sure you will be fine. One caveat of the formula 2000 gear box was it did not require you to engage the clutch to take it out of gear.
So your sequence would be begin with braking, knock it out of gear, bring engine revs up, engage clutch, shift, let clutch out. I found reading the pre school manual was confusing and intimidating. In reality it was no big deal. You know how to drive and you'll be fine. You may want to ask them if the gear box will allow you to just knock it out of gear...... In addition, one of the more interesting points of a formula car is the need to be on the brakes into the turn to create down force allowing the car to turn in. In my turbo, attemping to decrease lag I am back on the gas ASAP, so the brakes on into the turn was different but easily and quickly adapted too.
I also did the Bertil Roos school and I am sure you will be fine. One caveat of the formula 2000 gear box was it did not require you to engage the clutch to take it out of gear.
So your sequence would be begin with braking, knock it out of gear, bring engine revs up, engage clutch, shift, let clutch out. I found reading the pre school manual was confusing and intimidating. In reality it was no big deal. You know how to drive and you'll be fine. You may want to ask them if the gear box will allow you to just knock it out of gear...... In addition, one of the more interesting points of a formula car is the need to be on the brakes into the turn to create down force allowing the car to turn in. In my turbo, attemping to decrease lag I am back on the gas ASAP, so the brakes on into the turn was different but easily and quickly adapted too.
#19
Originally Posted by Geo
Good God.
Do the cars have wire wheels and drum brakes too? Talk about stuck in the 60s. Peace, love, dope......
snip...
For those suggesting it's necessary with straight-cut gears, you've actually got it backwards. With straight-cut gears you don't even need the clutch. Just blip between gears. I did it a number of times very smoothly in the Reynard 86SF F2000 cars I drove at school.
Do the cars have wire wheels and drum brakes too? Talk about stuck in the 60s. Peace, love, dope......
snip...
For those suggesting it's necessary with straight-cut gears, you've actually got it backwards. With straight-cut gears you don't even need the clutch. Just blip between gears. I did it a number of times very smoothly in the Reynard 86SF F2000 cars I drove at school.
It's not the straight cut gears that mean you don't need the clutch, it's the dog face selection of the gears. And if you have a dog box, it doesn't matter what the pattern of gear teeth is.
Furthermore, one reason (of several) to have straight cut gears in older gearboxes is to engare the gears by sliding them into mesh (not a constant mesh gearbox). If you drove one of those you would not only double declutch down through the gears, but also up!
Michael
#20
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Originally Posted by Larry Herman
I have not ever felt the requirement to perform lighting quick down-shifts, unless you want to row down through the gears and have a very close ratio six speed, like in the cup cars.
Also, we seem to have been talking exclusively about track use. Tracks are by their nature repetative. We do the same thing over and over again. We can plan ahead. But driving on the street is not like that. Often we need to do unexpected things quickly. An example of this is trundling along in traffic in 6th gear when suddenly a passing opportunity opens up. Then it can be very useful to be able to double-clutch quickly down in to 2nd for the pass. The difference in time between double-clutching and using the syncros can easily make the difference between being able to take the pass and not.
One thing that continues to amaze me is how different our driving styles can be. Yet the we often have very similar results. Maybe driving is more of an art than a science?
Stephen
#21
I add a second blip of the throttle before releasing the clutch after the downshift. First blip for gearbox engagement...second blip for engine engagement.
I'm with you. Even though it's not really necessary with a syncro gearbox, it's a skill that, IMHO, should be learned and used. There's nothing like coming into T1 at Summit Point in 5th, shifting directly into 2nd and having the shift lever just slide right in with zero resistance. Beautiful.
Also, on my commute, I have to shift into first twice while on a roll (to climb steep hills). Try shifting into first from 25mph some time without double de-clutching...it isn't pretty.
I'm with you. Even though it's not really necessary with a syncro gearbox, it's a skill that, IMHO, should be learned and used. There's nothing like coming into T1 at Summit Point in 5th, shifting directly into 2nd and having the shift lever just slide right in with zero resistance. Beautiful.
Also, on my commute, I have to shift into first twice while on a roll (to climb steep hills). Try shifting into first from 25mph some time without double de-clutching...it isn't pretty.
#24
Originally Posted by renvagn
Geza are you stopping in neutral with the clutch out blip for engine engagement??????
Shift to neutral.
Clutch out.
Blip throttle (for gearbox).
Clutch in.
Shift to lower gear.
Blip throttle again if necessary (for engine/drive train engagement).
Clutch out.
#25
Race Director
Originally Posted by mpaton
Pity to read such a denigratory post, and all the more so because it is WRONG!
It's not the straight cut gears that mean you don't need the clutch, it's the dog face selection of the gears. And if you have a dog box, it doesn't matter what the pattern of gear teeth is.
Furthermore, one reason (of several) to have straight cut gears in older gearboxes is to engare the gears by sliding them into mesh (not a constant mesh gearbox). If you drove one of those you would not only double declutch down through the gears, but also up!
Michael
It's not the straight cut gears that mean you don't need the clutch, it's the dog face selection of the gears. And if you have a dog box, it doesn't matter what the pattern of gear teeth is.
Furthermore, one reason (of several) to have straight cut gears in older gearboxes is to engare the gears by sliding them into mesh (not a constant mesh gearbox). If you drove one of those you would not only double declutch down through the gears, but also up!
Michael
#26
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Originally Posted by Geza
Clutch in.
Shift to neutral.
Clutch out.
Blip throttle (for gearbox).
Clutch in.
Shift to lower gear.
Blip throttle again if necessary (for engine/drive train engagement).
Clutch out.
Shift to neutral.
Clutch out.
Blip throttle (for gearbox).
Clutch in.
Shift to lower gear.
Blip throttle again if necessary (for engine/drive train engagement).
Clutch out.
Stephen
#27
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Originally Posted by Geo
Doesn't change the fact that clutching is not even required on a racing box. Double clutching is still an anachronism for drivers of cars with wire wheels while.
Stephen
#29
Mr. Excitement
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Originally Posted by Geza
Clutch in.
Shift to neutral.
Clutch out.
Blip throttle (for gearbox).
Clutch in.
Shift to lower gear.
Blip throttle again if necessary (for engine/drive train engagement).
Clutch out.
Shift to neutral.
Clutch out.
Blip throttle (for gearbox).
Clutch in.
Shift to lower gear.
Blip throttle again if necessary (for engine/drive train engagement).
Clutch out.
Brake until car slows, clutch in, shift with rev matching blip to lower gear. Why the neutral stop and blip? The gear box is already turning.
Also you are, during the first part, coasting or under braking without throttle control.
#30
Originally Posted by kurt M
Ok I am Konfuzed.
Brake until car slows, clutch in, shift with rev matching blip to lower gear. Why the neutral stop and blip? The gear box is already turning.
Also you are, during the first part, coasting or under braking without throttle control.
Brake until car slows, clutch in, shift with rev matching blip to lower gear. Why the neutral stop and blip? The gear box is already turning.
Also you are, during the first part, coasting or under braking without throttle control.
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