Jump to content
SAU Community

Recommended Posts

I've read a few books about driving lately as well as gotten advice from many about improving driving skills. Everyone suggests that a key high performance driving skill is learning to heel-toe on downshifts. What I have seen mixed comments about if you should single or double clutch when you downshift. What do you guys do?

Link to comment
https://www.sau.com.au/forums/topic/181699-downshifting/
Share on other sites

I only double clutch from 3rd into 2nd. I'm not sure why that is; I think its just force of habit. There's no mechanical reason for me to do so. I think even if I go from 4th to 2nd I'll still do a single clutch; definitely from 4th to 3rd is a single clutch manouvre.

I know that if I want to grab 1st from 2nd while on the move I need to double clutch; a simple heel-toe still locks me out of 1st.

Heel-toeing helps your rev match, which is good for avoiding compression locking when decellerating while not having to faff about with easing the clutch in. When you're driving close to the limits, doing stuff that stops the car from upsetting its balance is a good thing.

Link to comment
https://www.sau.com.au/forums/topic/181699-downshifting/#findComment-3299713
Share on other sites

Double clutching is one of those skills that once you have mastered just comes naturally every time that you change gears. It does put less stress on your gearbox and makes the shift smoother.

If you have a GTS-T then a simple mod is to install a GTR accelerator pedal. It is simple to install and has an extension out on the left side to make it easier to heel toe. These only cost about $20 and make heel toeing so much easier.

Link to comment
https://www.sau.com.au/forums/topic/181699-downshifting/#findComment-3299831
Share on other sites

  Yawn said:
Double clutching ie; clutch, shift to neutral, lift foot off clutch, clutch again, shift into gear?

Besides protecting your gearbox, I dont see much more point to it?

As one writer said after a while it simply becomes habit.

When you consider the correct technique for tarmac driving and cornering being to brake first then down change the double clutch down change makes no time difference whatsoever. The benefits are a smoother ride, less wear and tear on the gearbox, no compression lock. Certainly for street driving it is probably a marginal call doubling from 4th to 3rd but always 3rd to 2nd or 4th to 2nd.

In racing applications you would never think of not doubling and in fact is an important part of passing the observed driving test to gain a racing licence. After that you start to play with flat changing and left foot braking...a whole new tutorial on the left foot braking pros and cons.

Link to comment
https://www.sau.com.au/forums/topic/181699-downshifting/#findComment-3300415
Share on other sites

To be honest Im not sure myself... I think I use a mix of single and double clutching when Im heel-toe downshifting when driving spiritedly...

If its a normal downshift I will almost always double clutch. But yeah, when giving it a bit of stick you dont always have a lot of time (obviously) so sometimes I think I just single clutch?

One thing Ive noticed watching the pedal cam in Japanese clips (option, BM etc), is that a lot of drivers in those clips only single clutch when downshifting.

Link to comment
https://www.sau.com.au/forums/topic/181699-downshifting/#findComment-3300433
Share on other sites

  Victory said:
Double clutching is one of those skills that once you have mastered just comes naturally every time that you change gears. It does put less stress on your gearbox and makes the shift smoother.

If you have a GTS-T then a simple mod is to install a GTR accelerator pedal. It is simple to install and has an extension out on the left side to make it easier to heel toe. These only cost about $20 and make heel toeing so much easier.

I've been trying to double clutch all the time on the street just to ingrain the habit, but didn't really know if there was a reason to single or double. I've had a couple of ocassion on the track where I've definately upset the balance of the car downshifting without doing it. Spun once.

I have a GTR but installed Razo pedals anyway as they are height & width adjustable so it is easier to roll over on them to blip the accelerator.

post-33908-1187664649_thumb.jpg

Link to comment
https://www.sau.com.au/forums/topic/181699-downshifting/#findComment-3300631
Share on other sites

  Victory said:
If you have a GTS-T then a simple mod is to install a GTR accelerator pedal. It is simple to install and has an extension out on the left side to make it easier to heel toe. These only cost about $20 and make heel toeing so much easier.

you learn something new everyday.

will be getting one soon for my GTST

Link to comment
https://www.sau.com.au/forums/topic/181699-downshifting/#findComment-3300635
Share on other sites

The point of heel and toeing is to maintain braking while changing down ie your right foot works both the accelerator and the brake at the same time. With a syncromesh gearbox I can't see the point in double declutching, you can still match revs with speed without it. For racing it would be just too slow anyway. Well it should be :thumbsup:

Link to comment
https://www.sau.com.au/forums/topic/181699-downshifting/#findComment-3301307
Share on other sites

  260DET said:
The point of heel and toeing is to maintain braking while changing down ie your right foot works both the accelerator and the brake at the same time. With a syncromesh gearbox I can't see the point in double declutching, you can still match revs with speed without it. For racing it would be just too slow anyway. Well it should be :thumbsup:

I'm with him. What's the point of doubling?

Link to comment
https://www.sau.com.au/forums/topic/181699-downshifting/#findComment-3301587
Share on other sites

yeah in practice there's no real point double clutching, I guess in theory it saves your synchros a bit - its heal toeing/rev matching that is the important skill.

but 260DET....its not really slower, even with double clutching there are almost no places where the time to change down gears is longer than you are on the brakes anyway.

Link to comment
https://www.sau.com.au/forums/topic/181699-downshifting/#findComment-3301802
Share on other sites

I think a few people are confusing double clutching and heel-toeing.

in a synchro box there is no need to double clutch. rev matching with heel-toe is all you need to do. if you do that properly, the synchros get a harder time up-shifting on the track.

I'm with 260DET. definitely not enough time to double clutch downshift at places like Mt Cotton hillclimb. And even if there is, by the time you've done the second clutching while braking hard, your road speed will have changed so much it was all to no avail anyway.

Link to comment
https://www.sau.com.au/forums/topic/181699-downshifting/#findComment-3303090
Share on other sites

^ Exactly my thoughts.

Quiet Achiever: The benefits you stated can be achieved through rev matching alone and therefore theres no need to double clutch?

I can understand it being a habit, but besides that i stand by my point.

Link to comment
https://www.sau.com.au/forums/topic/181699-downshifting/#findComment-3303149
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Latest Posts

    • Who did you have do the installation? I actually know someone who is VERY familiar with the AVS gear. The main point of contact though would be your installer.   Where are you based in NZ?
    • Look, realistically, those are some fairly chunky connectors and wires so it is a reasonably fair bet that that loom was involved in the redirection of the fuel pump and/or ECU/ignition power for the immobiliser. It's also fair to be that the new immobiliser is essentially the same thing as the old one, and so it probably needs the same stuff done to make it do what it has to do. Given that you are talking about a car that no-one else here is familiar with (I mean your exact car) and an alarm that I've never heard of before and so probably not many others are familiar with, and that some wire monkey has been messing with it out of our sight, it seems reasonable that the wire monkey should be fixing this.
    • Wheel alignment immediately. Not "when I get around to it". And further to what Duncan said - you cannot just put camber arms on and shorten them. You will introduce bump steer far in excess of what the car had with stock arms. You need adjustable tension arms and they need to be shortened also. The simplest approach is to shorten them the same % as the stock ones. This will not be correct or optimal, but it will be better than any other guess. The correct way to set the lengths of both arms is to use a properly built/set up bump steer gauge and trial and error the adjustments until you hit the camber you need and want and have minimum bump steer in the range of motion that the wheel is expected to travel. And what Duncan said about toe is also very true. And you cannot change the camber arm without also affecting toe. So when you have adjustable arms on the back of a Skyline, the car either needs to go to a talented wheel aligner (not your local tyre shop dropout), or you need to be able to do this stuff yourself at home. Guess which approach I have taken? I have built my own gear for camber, toe and bump steer measurement and I do all this on the flattest bit of concrete I have, with some shims under the tyres on one side to level the car.
    • Thought I would get some advice from others on this situation.    Relevant info: R33 GTS25t Link G4x ECU Walbro 255LPH w/ OEM FP Relay (No relay mod) Scenario: I accidentally messed up my old AVS S5 (rev.1) at the start of the year and the cars been immobilised. Also the siren BBU has completely failed; so I decided to upgrade it.  I got a newer AVS S5 (rev.2?) installed on Friday. The guy removed the old one and its immobilisers. Tried to start it; the car cranks but doesnt start.  The new one was installed and all the alarm functions seem to be working as they should; still wouldn't start Went to bed; got up on Friday morning and decided to have a look into the no start problem. Found the car completely dead.  Charged the battery; plugged it back in and found the brake lights were stuck on.  Unplugging the brake pedal switch the lights turn off. Plug it back in and theyre stuck on again. I tested the switch (continuity test and resistance); all looks good (0-1kohm).  On talking to AVS; found its because of the rubber stopper on the brake pedal; sure enough the middle of it is missing so have ordered a new one. One of those wear items; which was confusing what was going on However when I try unplugging the STOP Light fuses (under the dash and under the hood) the brake light still stays on. Should those fuses not cut the brake light circuit?  I then checked the ECU; FP Speed Error.  Testing the pump again; I can hear the relay clicking every time I switch it to ON. I unplugged the pump and put the multimeter across the plug. No continuity; im seeing 0.6V (ECU signal?) and when it switches the relay I think its like 20mA or 200mA). Not seeing 12.4V / 7-9A. As far as I know; the Fuel Pump was wired through one of the immobiliser relays on the old alarm.  He pulled some thick gauged harness out with the old alarm wiring; which looks to me like it was to bridge connections into the immobilisers? Before it got immobilised it was running just fine.  Im at a loss to why the FP is getting no voltage; I thought maybe the FP was faulty (even though I havent even done 50km on the new pump) but no voltage at the harness plug.  Questions: Could it be he didnt reconnect the fuel pump when testing it after the old alarm removal (before installing the new alarm)?  Is this a case of bridging to the brake lights instead of the fuel pump circuit? It's a bit beyond me as I dont do a lot with electrical; so have tried my best to diagnose what I think seems to make sense.  Seeking advice if theres for sure an issue with the alarm install to get him back here; or if I do infact, need an auto electrician to diagnose it. 
    • Then, shorten them by 1cm, drop the car back down and have a visual look (or even better, use a spirit level across the wheel to see if you have less camber than before. You still want something like 1.5 for road use. Alternatively, if you have adjustable rear ride height (I assume you do if you have extreme camber wear), raise the suspension back to standard height until you can get it all aligned properly. Finally, keep in mind that wear on the inside of the tyre can be for incorrect toe, not just camber
×
×
  • Create New...