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Interesting technique I learned at Sebring

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ArizonaBOSS said:
The other thing is that if you're doing a heel-toe, you don't have to rip off a one-zillion RPM blip and try to downshift the moment you get on the brakes; you can wait to shift longer so the RPMs drop more and a more gentle blip is sufficient. Doesn't sound as cool but it's just as effective.
This is how I do it when not letting the technology do it for me. I wait until most of my braking is finished before starting my downshift.
 
steveespo said:
I'm not sure you're saying the same thing as Steve.

The hard part for me to understand about holding the clutch in during the braking is how the heck do you know/feel how much to blip with the engine and trans de-coupled for so long? It seems it would be tough to make clean/perfect downshifts. I guess I gotta try it to know either way.

I think we were getting at the same thing...that rear wheel hop can cause bigger problems than the potential benefit of helping you decel.

Candidly, I typically row trough the gears with a throttle blip when going down more than one gear for the same reason you outline. It's tough to gauge the rpm you need to match. I really couldn't say what's best for getting around the track the fastest way possible, but the theory of holding in the clutch and doing one down shift at the end of the brake zone does make sense to me for the following reason...fewer inputs/actions mean fewer chances to throw off the balance of the car. It also seems like it would allows you to slow down in a "neutral" postion without the engine applying any force (positive or negative) that may potentially upset the car.

I think it might be worth spending some time trying both techniques at my next event to see if there is a clear advantage either way.
 

Grant 302

basic and well known psychic
cosm3os said:
If you are unsettling the car you aren't getting the blip right.
Yeah, I guess I gotta take back the part about clutch engagement speed. If the blip is right, then clutch speed doesn't matter.

ArizonaBOSS said:
The other thing is that if you're doing a heel-toe, you don't have to rip off a one-zillion RPM blip and try to downshift the moment you get on the brakes; you can wait to shift longer so the RPMs drop more and a more gentle blip is sufficient. Doesn't sound as cool but it's just as effective.

Agreed. I always try to complete the shifts just before initiating the turn. The drop from 4-2 takes a big blip and I'm definitely smoother but probably slower going from 4-3-2. Sample here:
[youtube]https://www.youtube.com/watch?v=_eoqoWm3WR8[/youtube]
 
ArizonaBOSS said:
That is what the instructors will say, but their job is to get the student to manage the vehicle dynamics and get them around the track safely--by taking the downshifting out of the equation they leave the student with more mental capacity to focus on the other things going on around them.

This is definitely not the fastest way around the track, however.

The other thing is that if you're doing a heel-toe, you don't have to rip off a one-zillion RPM blip and try to downshift the moment you get on the brakes; you can wait to shift longer so the RPMs drop more and a more gentle blip is sufficient. Doesn't sound as cool but it's just as effective.

That is the best way. A lot of new drivers will want to do the down shift to early. I have never heard of teaching to hold the clutch in in a break zone but if done it must be as you say to slow things down for the student.
 
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I know this is sacrilege, but being a kart racer.. I've never heel and toed a downshift in my life. My SCCA instructor was asking why, I explained the kart thing to him and told him that's why God made synchronizers.

about 1:46 in the video

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

steveespo

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Still if you watch the driver he does get hard on the brakes and kill a lot of speed before downshifting. Those cars also have dog ring synchros and straight cut gear teeth, what are called "crash boxes" they are designed to be shifted clutch less up and with little or no clutch down. The throttle is used to match revs and the driver pushes the lever hard to make the gears mesh. Very expensive and high maintenance gearboxes. You cannot shift an MT-82 or even a TR-6060 like that, at least not for long.
Steve
 
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steveespo said:
Still if you watch the driver he does get hard on the brakes and kill a lot of speed before downshifting. Those cars also have dog ring synchros and straight cut gear teeth, what are called "crash boxes" they are designed to be shifted clutch less up and with little or no clutch down. The throttle is used to match revs and the driver pushes the lever hard to make the gears mesh. Very expensive and high maintenance gearboxes. You cannot shift an MT-82 or even a TR-6060 like that, at least not for long.
Steve


I just put that up there as an example, that is more or less how I do it, stand on the binders and go down through the gears, not as aggressive but that's about it.
 

steveespo

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I agree with you Rob, I just don't advocate using the engine as a brake before killing a good portion of the speed(therefore rpm) with the wheel brakes. I think everyone is saying that but don't want to have the OP think otherwise. Too much risk in mechanical over rev when downshifting too early. My first instructor asked me, "what's cheaper, brake pads and rotors or a new clutch and valve spring job?"
Steve
 

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