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Double clutch or Single clutch?

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Old 07-12-2018, 08:25 AM
  #46  
Yargk
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Originally Posted by Izzone
I used to heel toe my vintage race car...had to rebuild the trans (915) often

put a trans cooler in the car, and temp gage in trans. Cooler helped but in 90 min enduros it still got too hot

learned to double clutch, and the need for a trans cooler was gone...I’d run seasons on a 915 year box with 380ish hp thru it

if u learn to do it correct u can skip shift without upsetting the car...I’d go 5th to 1st

used to to race my friends 996 cup and double clutched it

it does help a transmission last a long time...much longer than Heel toe

it’s no slower...I can show video of how quick u can do it with proper muscle memory
Really cool to hear this. I started double-clutching with my WRX, the 5-speeds are terrible. It's absolutely true that it's often "not necessary" in modern synchro transmissions, but I'm sure if done properly it will extend the life of those synchros. Also, the reason it's not slower is that, unless the transmission is very good or you don't care about abusing it, there should be a very small pause when shifting (and not double-clutching) as you feel the synchros work. If you double clutch well, it just drops into gear because you did the synchro's work for it, which pretty much negates the time taken to double-clutch.
Old 07-12-2018, 02:05 PM
  #47  
Mike Murphy
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I’m going to have to go on record to say that double-clutching would almost have to certainly be slower than single clutching. Because: introducing an extra step, even if that step by itself doesn’t increase latency, has the potential to increase latency over the long haul. This is why a manual trans car can be just as fast as PDK, but overall, PDK will win in the end.

Regardless, these small numbers are just that. Seconds or milliseconds. Yet we chose manual over PDK, so might as well double clutch if it makes you happy.
Old 07-12-2018, 03:16 PM
  #48  
FourT6and2
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Originally Posted by murphyslaw1978
I’m going to have to go on record to say that double-clutching would almost have to certainly be slower than single clutching. Because: introducing an extra step, even if that step by itself doesn’t increase latency, has the potential to increase latency over the long haul. This is why a manual trans car can be just as fast as PDK, but overall, PDK will win in the end.

Regardless, these small numbers are just that. Seconds or milliseconds. Yet we chose manual over PDK, so might as well double clutch if it makes you happy.
My dad used to refuse to use turn signals. Said it would just wear out the bulb. So yeah, double clutch all you want
Old 07-12-2018, 03:26 PM
  #49  
GrantG
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Originally Posted by murphyslaw1978
I’m going to have to go on record to say that double-clutching would almost have to certainly be slower than single clutching. Because: introducing an extra step, even if that step by itself doesn’t increase latency, has the potential to increase latency over the long haul. This is why a manual trans car can be just as fast as PDK, but overall, PDK will win in the end.

Regardless, these small numbers are just that. Seconds or milliseconds. Yet we chose manual over PDK, so might as well double clutch if it makes you happy.

I don't think you are understanding how a double-clutch heel/toe downshift works. It is managed under braking. Completing the downshift (with or without double-clutching) takes less time than the time required to brake for the approaching corner. So, there are 0 milliseconds delay of the laptime by introducing this extra step. So an infinite number of 0 millisecond delays is still 0 delay...

BTW, I am not suggesting this is necessary with a new GT3 (quite the contrary, unless going into first gear from 30mph), but if someone wanted to do it, the lost time would not be a reason not to do so...
Old 07-12-2018, 09:08 PM
  #50  
Mike Murphy
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^^ Sure, if you are braking at 135mph off the main straight at Road America in 5th, and downshifting to 3rd to enter turn 1 at say 65mph. Because there’s plenty of time to brake and shift, etc. A skilled driver might even take a drag off the cigarette here and lose zero time, lol.

But what about much shorter time duration of braking events, such as a single downshift and a light tap of the brakes to get through ‘the kink’ or similar turn? If the time duration allotted during the event is long, we have lots of time to complete double clutching. If the time is short, we might be pressed.

Also, I’m suggesting that humans won’t perfectly execute all maneauvers exactly every time. Meaning that there’s room for error would could add latency through the course of an entire 30-mins worth of laps...

I feel like the exact same debate/argument we are having is not unlike left-foot braking versus right-foot braking. There are those that swear that right foot braking does not add any latency. And many resist left-foot braking. However, those that have tried both and actually spent the time to master both usually come away with the experience that however small the advantage might be, left foot braking might be a tad faster. And even on some tracks where some folks right-foot brake 99% of the time, there are some turns that one would actually left-foot brake on a specific turn to gain a slight advantage there.

To-MAY-toe, To-MAH-toe I guess. But I just don’t see any fast racar drivers or even faster track car drivers double clutching.
Old 07-13-2018, 12:18 AM
  #51  
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Originally Posted by murphyslaw1978
To-MAY-toe, To-MAH-toe I guess. But I just don’t see any fast racar drivers or even faster track car drivers double clutching.
If you spent time with vintage racing, you’d see some very quick drivers doing it

I’ve passed some quick modern track cars in my ‘73 while doing it...

But the average modern quick track car gets quicker every year and the fast vintage stuff does not (aside from improvements in tires)...
Old 07-13-2018, 03:23 AM
  #52  
mooty
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old car double clutch
new gT car no use
if your gt3 gear box dies b/c you are single clutching, you are doing way too many other things wrong.
Old 07-13-2018, 07:46 AM
  #53  
Mike Murphy
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Originally Posted by GrantG

If you spent time with vintage racing, you’d see some very quick drivers doing it

I’ve passed some quick modern track cars in my ‘73 while doing it...

But the average modern quick track car gets quicker every year and the fast vintage stuff does not (aside from improvements in tires)...
Touché

I wonder how much faster you would be passing that modern track car if we switched drivers, lol.

Thank goodness for tire technology and skilled drivers keeping the vintage stuff alive. I hope it never goes away
Old 07-13-2018, 10:00 AM
  #54  
Waxer
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Originally Posted by Ascend
Bud at least I'm trying to learn and improve? We all start somewhere.
Your stalling? Like from 2nd to 3rd etc...(hard to understand how this is happening) or from a stop? If the latter it has 0 to do with double clutching. If the former stop trying to double clutch ... you don’t need it. Just practice single clutching and drive. That’s what synchronized are for.

Ditto what Mooty said.

You asked. There’s your answer. Beyond this if you still insist on double clutching we can’t help you.


Last edited by Waxer; 07-13-2018 at 10:33 PM.



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