Interesting technique I learned at Sebring

[Track50h]

Let me start off by saying I'm not a seasoned HPDE driver I'm still kind of starting off I have done 3 events at Sebring plus a few autocross events I did to just polish my skills and learn the limits of my car at a slower speed. Anyway My instructor has a an interesting downshifting techique I found very useful if not smoother and faster then the regular down heel-toe down shift. When going into the Corner by Chateau Elan it is necessary to down shift form 4th to 2nd, What he does is hold in the clutch and heel toe downshifts from 4th to 3rd to 2nd with out releasing the clutch in the 4th to 3rd down shift. I tried it my self and thought about it through out the night and concluded it was faster, smoother and probably puts less stress on the drivetrain then down shifting the conventional way.

Just wanted to share this with you all and open it up for discussion.

 

[VoodooBoss]

Nice tip. Or you could install an Auto-Blip. ;D

 

[Track50h]

NEVAR!!!! hahahaha

 

[cosm3os]

He's wasting gas! The way he's doing it is no different than just doing one later blip and going from 4-2 in one shot only you are adding a blip (hence, waste of gas). What's the point of matching revs if you aren't letting the clutch out to engage the gear that you are trying to match? Plus, he's not getting the benefit of engine braking while he's got the clutch in.

 

[JScheier]

What's the point of matching revs if you aren't letting the clutch out to engage the gear that you are trying to match? Plus, he's not getting the benefit of engine braking while he's got the clutch in.

+1

 

[WinterSucks]

I think everyone is misunderstanding. It sounds like he is just rowing the gears to me, not revving until ready to engage 2nd gear. I can see that since the motions are more straight lines from 4 to 3 then 3 to 2 rather than going up and over from 4th to 2nd. It does feel more difficult to me to go 4 to 2, maybe because it is not a smooth motion.

 

[cosm3os]

Still, if he's got the clutch in the whole time, it is inefficient braking.

 

[Steelhorse]

It is a waste of time really. Also in what modern car do you really worry about engine braking in a heavy brake zone? That is also a waste and hard on your engine. Todays modern brakes should be getting the job done.

 

[cosm3os]

It is a waste of time really. Also in what modern car do you really worry about engine braking in a heavy brake zone? That is also a waste and hard on your engine. Todays modern brakes should be getting the job done.

That's like saying, "why track out that last 2 feet on exit, I've got 400hp to make it up." If you want 10/10ths, you gotta use 10/10ths!

 

[WinterSucks]

I am not experienced on track, but my thought is that if you have the engine in gear while braking, even if the engine is coming down from a high rpm and engine braking as hard as possible, that the brake force will be greater than the engine braking and you will just end up using part of the braking force to drag the engine down. IF you are braking that hard, which I doubt is the case on all corners.

 

[ArizonaBOSS]

 

[cosm3os]

I'll take a shot at it.

When the engine is braking it is generating an opposite force--instead of applying torque in the forward direction it is resisting the rotation of the transmission, it is trying to slow down because the vacuum in the intake and cylinders is acting on the pistons with much greater force.

Your brakes are also trying to stop the rotation of the transmission (through the axles, diff, and driveshaft). Therefore, the forces of the brakes and the engine are combined. If you disengage the clutch, you no longer have the engine resisting the transmission, so there's less overall force working against the transmission.

 

[Grant 302]

The way he's doing it is no different than just doing one later blip and going from 4-2 in one shot only you are adding a blip

This.

Here's a sample of going straight from 4 to 2 with one big blip. Turn 11 at Laguna Seca.
[youtube]https://www.youtube.com/watch?v=Zyg_y5D1-cs[/youtube]

 

[steveespo]

I do 5-3 direct shifts many times. I don't like to do 4-2 just because I feel second gear needs the most care, seems to be the most fragile so if I need 2nd I will go 4-blip-3- blip-2. I also use brakes for big decals then downshift, and engine braking for smaller decels without downshifts. Just depends on what kind of corner is coming and how I want to weight the car. Downshifting while carrying a lot of speed can cause rear wheel lock up and axle hop which will help you overshoot your turn in.
Steve

 

[KBBOSS1086]

I've been told by several instructors / racers (at Track attack among others) that the best way to brake and maintain good car balance is to hold the clutch in until your breaking is complete (when breaking in conjunction with down shifting) and heel / toe only at the end of the braking zone. As Steve mentioned, using the rear wheels (engine breaking) under heavy decel w/ a down shift can cause wheel hop, potentially leading to an unbalanced car and in worst case scenarios a spin. This is comparable to having way too much rear break dialed in to the car.

 

[Grant 302]

I do 5-3 direct shifts many times. I don't like to do 4-2 just because I feel second gear needs the most care, seems to be the most fragile so if I need 2nd I will go 4-blip-3- blip-2. I also use brakes for big decals then downshift, and engine braking for smaller decels without downshifts. Just depends on what kind of corner is coming and how I want to weight the car. Downshifting while carrying a lot of speed can cause rear wheel lock up and axle hop which will help you overshoot your turn in.
Steve

You mean like I did in my video? Guilty of all three. ;D Most of the day went 4-3-2, but I was working on braking later and went straight for 2nd at least a few times. Even hitting the 3-2 takes a bigger blip because of the greater ratio drop 1:1.4 vs. 1:1.3 for the 5-4 and 4-3. Coincidentally why many people can't hit 2-1 because of the 1:1.5 ratio difference.

But seriously, I think it's mostly missing the blip and/or letting the clutch out too quickly that would cause the lockup/hop problems. I think I do a bit of both in that video.

I've been told by several instructors / racers (at Track attack among others) that the best way to brake and maintain good car balance is to hold the clutch in until your breaking is complete (when breaking in conjunction with down shifting) and heel / toe only at the end of the braking zone. As Steve mentioned, using the rear wheels (engine breaking) under heavy decel w/ a down shift can cause wheel hop, potentially leading to an unbalanced car and in worst case scenarios a spin. This is comparable to having way too much rear break dialed in to the car.

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.

 

[cosm3os]

If you are unsettling the car you aren't getting the blip right.

 

[steveespo]

If you are unsettling the car you aren't getting the blip right.

Kyle is correct.
#AutoBlip
There is no shame if you want to keep up with M3s, 911 PDK or GTRs.
The consistency takes much error out and lets me concentrate on the brake pedal and steering inputs.
Steve

 

[VoodooBoss]

Kyle is correct.
#AutoBlip
There is no shame if you want to keep up with M3s, 911 PDK or GTRs.
The consistency takes much error out and lets me concentrate on the brake pedal and steering inputs.
Steve

Don't leave the paddock without it. ;D

https://trackmustangsonline.com/index.php?topic=4435.200

 

[ArizonaBOSS]

I've been told by several instructors / racers (at Track attack among others) that the best way to brake and maintain good car balance is to hold the clutch in until your breaking is complete (when breaking in conjunction with down shifting) and heel / toe only at the end of the braking zone. As Steve mentioned, using the rear wheels (engine breaking) under heavy decel w/ a down shift can cause wheel hop, potentially leading to an unbalanced car and in worst case scenarios a spin. This is comparable to having way too much rear break dialed in to the car.

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.