Two stage accelerator?

[Ryan_R]

Well, it works just fine in auto mode as well, as I've been playing with it this week.

[Brian916]

my 2c worth (Yeah, I remeber them and the fact you could actually get 6 lollies for that...)

In the 'bad old days', auto's a combination of torque/vacuum to change down -'kick down'- and there was no switch. My VL commodore had one of the first electronic controlled boxes, with a 'sport' function. Electronic autos use switch to change the logic from 'economy' mode to 'sport' (Sport - change the shift point to higher in the rev range and hold gears longer) mode as well as activating an elecronic 'kick down' function.

From what I've read, the switch is either a single or dual funtion one.

1. Switches logic to 'sport' and kicks back a gear (or two)
2. Switches logic for 'sport' mode only
3. Switches on a 'kick down'

Oh, there's also an article I read somewhere where one of the vehicle makers (VW? through Porche/Audi/Lambo?) were also going to have a dual ECU map for the engine (Sport and economy again) and doing the foot-to-the-floor would change logic to sport on the box, kick down a couple of gears, and change the engine map to a 'less fuel efficient' one.


Now, this is what I've read and been told by auto tranny repairers (replacers now as most can't be rebuilt anymore). Seemed logical.

[Corey_R]

Yeah - we had a VL commodore. There was a "sports/power" switch on the auto selector, but there wasn't a kick-down switch under the pedal.

[MiiLos]

i had the switch on my MkV TDi and all it did once engaged was drop a gear or two to get faster acceleration - it did this weather i was in drive mode, or sport mode. oh an i dont remember ever trying it while i was in manual mode.

[brad]

The reason why it is called a "kickdown" switch is because in the old days, you had to mash the throttle into the floor quite hard & fast to get the gearbox to change down a gear (or if you had a real fancy gearbox, 2 gears). This was to create a dramatic drop in vacuum at the kickdown modulator (rear rhs on a trimatic IIRC) which in combination with the kickdown cable (throttle position cable) would tell the gearbox to drop a gear or two. If you've ever seen a holden or falcon driving along belching plumes of white smoke, it has ruptured the diaphram in the modulator & is sucking auto trans fluid straight into the inlet.

I can't think of any cars that had an electrical kickdown switch as such (but I'm sure there were) but a lot of Toyotas had a switch to turn the the AC off at 80%+ throttle, thus giving a little extra power for overtaking.

[aussiegtidude]

My BMW 325 has a distinct kickdown click, it is even mentioned in the instruction book, my partners Renault has one and so does the new 350CGI we have but I haven't checked the book to see if it is mentioned.

They are fairly common and I have seen them in Toyota, Audi, Holden (European builds) and I think an auto Porsche I drove but I can't remember about that one.

[Brian916]

And there was the 'kickdown' cable on some older cars too.

Back to the VL, I was sure the 4speed had a throttle switch under the pedal..... Meh, I've had so many cars over the years, they all blend into each other is many cases.

The Golf stands out from the crowd as does the D4 though - although today after getting a nail in ANOTHER tyre (4 weeks, 2 nails) I'm not happy! 30 yrs of driving without a puncture, and BAM, 2 in 4 weeks.

[velly_16v_cab]

my 2c worth (Yeah, I remeber them and the fact you could actually get 6 lollies for that...)

In the 'bad old days', auto's a combination of torque/vacuum to change down -'kick down'- and there was no switch. My VL commodore had one of the first electronic controlled boxes, with a 'sport' function. Electronic autos use switch to change the logic from 'economy' mode to 'sport' (Sport - change the shift point to higher in the rev range and hold gears longer) mode as well as activating an elecronic 'kick down' function.

From what I've read, the switch is either a single or dual funtion one.

1. Switches logic to 'sport' and kicks back a gear (or two)
2. Switches logic for 'sport' mode only
3. Switches on a 'kick down'

Oh, there's also an article I read somewhere where one of the vehicle makers (VW? through Porche/Audi/Lambo?) were also going to have a dual ECU map for the engine (Sport and economy again) and doing the foot-to-the-floor would change logic to sport on the box, kick down a couple of gears, and change the engine map to a 'less fuel efficient' one.


Now, this is what I've read and been told by auto tranny repairers (replacers now as most can't be rebuilt anymore). Seemed logical.

you are pretty much on the money here....I know that you can program the ECU not to give full torque in 1st gear, this is to protect the transmission. With all the electronics in the car you can tune many different things t give different feel.
Apart from the ECU, you can tune the trans and even the throttle pedal.

Some OEM's have a 'detent' in the throttle which defines a 'kick down' point. But you can get 100 throotle before you hit this detent.
Most US car will ONLY get 100 throttle when your foot in on the floor.

[brad]

The Golf stands out from the crowd as does the D4 though - although today after getting a nail in ANOTHER tyre (4 weeks, 2 nails) I'm not happy! 30 yrs of driving without a puncture, and BAM, 2 in 4 weeks.

Is that a straight groove tyre like a ContiSportContact2? I had the same issue, no punctires for 10+ years & then had several as soon as I got the Skoda with CSC2 - all on the passengers rear. I think the front tyres tread straightens out the screw/nail & flicks it up at just the right angle to go in the rear tyre.

[Ryan_R]

I wouldn't mind detuning my first gear - any info on how to/who can do it?

[Brian916]

Is that a straight groove tyre like a ContiSportContact2? I had the same issue, no punctires for 10+ years & then had several as soon as I got the Skoda with CSC2 - all on the passengers rear.

These are directional Dunlop Sportmax or some such. I'll survive I guess.

Now, these switches and their uses is becoming bigger than Ben Hur. The torque limiting in first gear is common on motorcycles as the gearbox on some of the larger capacity bikes is a little fragile. In fact some of them give slightly more torque in each higher gear till 4th when you have it all available for 4/5/6. No reason why it will not work in a car.

[stickshift3000]

The torque limiting in first gear is common on motorcycles as the gearbox on some of the larger capacity bikes is a little fragile.

Also so it's less prone to flipping!

Suzuki commonly retard the ignition on the first 4 gears of their roadbikes - this doesn't make them much slower, just more manageable.

[Brian916]

My last zook had that 'feature' but I fitted a 'gear indicator pro' that showed what geat the 1250 bandit was in (surprisingly useful!) and let me choose the level of ingition retard in the first 4 gears. Had settings from 1 to 5. I used setting 4 as it was the best one for what I was doing riding wise. Certainly pulled harder in the first 4 gears!

I wish cars were as easy to power up as bikes - the bike went from 92hp at the wheel to 118 with simple additions of an open airbox with free flow filter, exhaust can (left the cat in) and a power commander that was custom mapping.

Cars you usually have to take the word of the people selling the ecu upgrade.