Been meaning to ask this for a while but fear of ridicule has stopped me...

Why are auto boxes never installed into Locosts, or any kit for that matter?

I certainly understand the 'drivers car' concept, no ABS, no servo, no PAS etc, etc.
But surely it simplifies the build and with such demanding cars would allow you to fully concentrate on the driving.
It would also open up the choice of power plants to include some of the bigger capacity 'luxury' cars.

I don't know whether I would want a weekend toy to be auto but since owning an old Jag many years ago I was sold on auto transmission and not owned a manual for 10 years. And certainly the 3.5 SD1, Rover Sterling and Granada 24v were actually fun for such big cars.

Am I missing a fundamental design reason why it's not done or is it purely preference.

I eagerly await ridicule...

John

people like changing gear and having the control of holding the gear (ie the auto box not changing gear mid bend).

If you're really interested I've got an auto box for a crossflow sat in a car waiting for a good home.

Hi Mike
Thats was one drawback I considered, would make life interesting kicking down 2 gears mid corner in the wet. You can always overide the auto and select manually.

Thanks for the offer, but I'll see how I get on with a sequential box....

John

the problems as suggested above are not being able to control when the gear is changed. both acceleration, short shifting (in wet) and engine breaking are effectively impossible in an auto, which on a spirited drive no a locost I believe are part of the fun, enjoyment and attainment of speed, especially when cornering.

Ned.

F1 cars are auto, so it shouldnr be impossible to make a predictable drivable car.....

some boxes have a sport mode - that effectively short shifts if turned off.

Some auto boxes are heavier and bulkier than the manuals - that could be an issue.

Another point is that many locost owners are performance obsessed - and having a fluid link (torque converter) in the drive chain just loses perfromance.


The auto could also make the car too lively at the rear. A torue converter does just that - it increases effective torque. This is most noticeable from take off - my jag xjs was 'on ice' in the wet - just a touch of throttle would break the rear away. If you have ever driven an average american car, you will find it really easy to chirp the front tyres, due to some part, the high torque applied at take off.


atb


steve


PS - no one has done a diesel locost either - again, down to the performance obsession methinks...

[Edited on 6/5/04 by stephen_gusterson]

but if there was a gearbox suitable for the golf td gti 150bhp engine, i'd give it a go.. bucket loads of torque and more power than a zetec/duratec.

Ned.

Steve, good point about the F1 cars.

Certainly an auto box is heavier and less efficient at transmitting the power of the engine to the wheels, having said that, at the traffic light drag strip with all other things being equal, I'd bet on the auto.
MCN did a piece a few months ago on auto v's manual and concluded that in the acceleration stakes an auto box wins. They even found that some of the big scooters were out dragging the sports bikes up to road speed limits.

John

silly question, but if some of the big scooters outdrag the sportsbikes, how do they keep the front wheel down as the CoG on a scooter must be higher than a bike, and if they out accelerate the torque/reaction must be at least equal surely?

Ned.

Morning Ned.
Short answer is I dunno.
Howerver the COG is lower on a scooter due the the engine being slung just in front of the rear wheel and I the smaller wheels would reduce the 'turning' effect around the rear axle.
The big scoots are also long ugly things, basically overgrown speedflights. I don't know if its been put into production yet, but one of the Japs was developing a 1000cc scooter..... Why....?

John

The reason us US guys dont fit them is to keep them from being stolen. Automatics are all people know here. the first time my wife had to drive my car, she came back and asked me why I have 2 brakes, go figure.

I recently borrowed a new rover 25 1.6 with auto. All the new rover autos are fitted with semi auto box where u can knock it to the side for sport mode where it will stay in gear longer, or u can knock it back and forward to change gear when u want.

It seemed quite an electrically controlled box, if i floored it, it would drop a gear (as most autos) but then it would just climb to 3000 rpm and stay there if i floored it a bit more it would drop another gear and the revs would rise to 4000 but stay there. It was a wierd sound, the engine being limited to those revs and still seem like it was accelerating.

The box was fine for cruising and motorway driving. Using the manual change made it a bit more fun, but the torque converter made it feel like i had my foot half pressing the clutch down. Its a very indirect feel and one i wouldnt want in a sports car. Im sure autos in bigger sportier cars are alot better, but if you had one in a locost im sure it would be more lo tech than the rover one.

After 2 weeks of driving it i couldnt wait to get back to my fiesta and change the gears myself!

hate to differ ...... well ok, i don't.

Westfield did a diesel, called it the weisel. high mpg and pretty quick acceleration - only problem was a heavy and underpowered (by todays standards) ford 1.8 turbo diesel in my view.

the 'constantly slipping clutch' is a typical effect of an auto.

later boxes have a 'lock' feature that locks the torque converter after a certain amount of revs. American cars have the feature to lower emissions.

atb


stev

feel free to correct me, but i was quite sure that F1 cars arent true auto. i thought it was preprogrammed where to change gear on the track, when to leave it in gear etc, with override buttons onboard. and others are only auto one way, and you downshift manually.

not sure how it is this season, think autos are banned now arent they?

ps i used to drive an omega 3ltr auto, was very boring, even dangerous. dropping gears on roundabouts, and impossible to hold/control slides without locking it in gears, which is crappy anyway. when i make a locost MPV i may do auto though.

[Edited on 6/5/04 by JoelP]

" i used to drive an omega "


thats the problem in a nutshell, isnt it? regardless of box...


atb

steve

Just about the only slush boxes suitable for a book sized Locost are the ancient BW 35 and 45 or if you go all germanic and BMW donor the ZF --- the Ford C4 and C5 boxes are so unreliable they aren't worth a considering. The model 35 was offered most british medium car of the 60s/70s right up to the series 1 4.2 XJ6 and also auto versions of the MK2 Cortina and MK1 escort, it was ultra reliable in cars under 2 litres (not so behind a Rover V8 or Jag engine) but it had lousy ratios for sporting use. The 45 was mainly used by Chrysler UK and BL had 4 speeds but worse ratios.

But go up to Rover V8 size and an auto box becomes a better proposition the GM box in later SD1 models was a good box.

With most epicyclic autoboxes the chassis would need to be altered to accomodate the gearbox sump.

quote:

---

Originally posted by stephen_gusterson
" i used to drive an omega "


thats the problem in a nutshell, isnt it? regardless of box...


atb

steve

---

quote:

---

Originally posted by stephen_gusterson
" i used to drive an omega "


thats the problem in a nutshell, isnt it? regardless of box...


atb

steve

---

I used to like the princess / ambassador, but that would get similarly slagged.

We have a guy here at work who has an omega. Its his second as a company car, and hes gutted that its just gone obsolete cos he was just about to order a third.

He recons he uses it cos he needs to get old people in the back and it has a lot of room.

Strange, most people want a snazzy car to entice younger ladies in the back

quote:

---

Originally posted by JoelP
feel free to correct me, but i was quite sure that F1 cars arent true auto. i thought it was preprogrammed where to change gear on the track, when to leave it in gear etc, with override buttons onboard. and others are only auto one way, and you downshift manually.

not sure how it is this season, think autos

---

A few interesting points!

Last first, a 7 speed auto would definitely NOT be 4 feet long!! I saw the GM prototype 7 speed at Strasbourg transmission plant!! (we supply parts for these 'boxes to GM) They will be in cars in the near future!!! They fit in the same casing as the pre-production 6 speed auto, which in turn uses a very slightly modded 5 speed auto casing!

Next, whilst I do not like auto boxes because of the fact that they basically "waste" a large proportion of engine power during convertor slip periods, I have to admire the new generation "infinitely variable transmissions"

Whether you like the idea or not, these are the future. (so much so I have bought shares in the leading development company!)

I will try and explain!! old CVT's used belts, either rubber (DAF Variomatic) or Steel Segment Push Belt (various manufacturers)

Torotrak are the leading developer of a new transmission based on a purely mechanical toroidal variator unit coupled with a differential shunt.

Basically if you think about an epicyclic gearbox (car diff. or sturmey archer bike hub), you get the different speeds by locking or unlocking either the Annulus gear, sun gears or planet carrier. A differential shunt uses this effect by using carefully sized gears and driving one compononent directly from the engine permanently connected, the second component through a variable speed gearbox, and connecting the third component to the wheels. If you think it through and have the right sized gears, at a certain RPM of the engine, the permanent engine input will exactly cancel out the input from the variator and give a "geared neutral" i.e. the car is stationary. Any increase in the variable speed gearbox output will cause the car to move off. Any reduction in output will give reverse.

By coupling this "differential shunt" to a electro-hydraulically controlled infinitely variable "gearbox" (which has no torque convertor or fluid drive, it is mechanical drive and extremely efficient, basically the same efficiency as a manual gearbox) you get infinitely variable forward gears with the efficiency of a manual gearbox, together with geared neutral which does away with the need for a clutch, and geared reverse.

The beauty of it all is that you can then combine the gearbox with the engine into a hybrid power unit, and you accellerator just sets the deman for speed of the vehicle. In very simple terms, if you accellerate slowly and gradually to a cruising speed, the variatot would maintain a highish ratio and keep the engine revs low and around the engine's peak torque band. If you booted it flat out from a standing start, the transmission would allow the engine to achieve max power rpm and then load the engine without pulling the revs down by more than a preset level. (just like dialling in the load on an electrical engine dyno) This would give the fastest acceleration possible, much quicker than a manual 'box could ever achieve!!

The possibilities are endless. Torotrak has a patented system to fit to off road vehicles where you switch over to another driving mode (called Total Off-Road Control) and take your feet of the pedals. You dial in the desired speed on control on the dash and the vehicle drives at that speed! Uphill, downhill, makes no odds, using the computer control of the engine and gearbox together, uphill is easy, but downhill the computer can back off the gearbox ratio to slow down the vehicle, right to a standstill, even driving with some reverse effort if wheels lock up! It can then engage reverse on the same dash control and reverse back up the hill with no gearchange of loss of the flow of power.

ABSOLUTELY AMAZING is the only way to describe it!!

Which reminds me Austin fitted a fully variable belt less transmision in the 1920s ! --- of course it only lasted about 5 minutes in the hands of Joe public.

I love automatics on cars with really big engines but find anything with a fully variable ratio system totally horrible to drive.

I thought that until I drove one (prototype) with non-belt type transmission and electronic control, then I was sold on the idea! Full engine braking on lift off (more so than with manual) faster accelleration than a manual with no "slip", the whole experience just felt like driving a very lightweight car where you get the feeling of the car instantly speeding up and slowing down in time with your right foot, with none of the usual elastic feeling you get with even manual gearboxes. Just wear earplugs and don't look at the revcounter and it just feels like a bigger engined car with no gears and direct drive!! Performance with this type of transmission on a big v8 engine is shattering!!

Sensitivity of the "throttle pedal" (which of course it isn't any more, just a faster/slower pedal!) is exponential from any given point, i.e. at any point in the pedal's travel, a slight movement gives fine control i.e. good mid-corner control, and large sudden movement gives huge response (great powerslides and fun!!!)

quote:

---

Originally posted by stephen_gusterson
I used to like the princess / ambassador, but that would get similarly slagged.

We have a guy here at work who has an omega. Its his second as a company car, and hes gutted that its just gone obsolete cos he was just about to order a third.

He recons he uses it cos he needs to get old people in the back and it has a lot of room.

Strange, most people want a snazzy car to entice younger ladies in the back

---

quote:

---

Originally posted by JoelP


1996, heated back seats, less the £2k. find a similar car like that though?

---

NS Dev.
We use something at work called a 'KOP variator'. Its used as a variable drive for small conveyors. There is no belt in them and they are infinately variable from Zero RPM up to max motor speed. Fantastic bit of kit but bloody complex inside. Sound like a similar idea to the auto box you described above.

I look forward to seeing them installed on production cars, they sound great.

John

I had a 620 2 litre auto - 94 model - for 3 years.

avoid the auto - its got crap gearing and dies between 35 - 50 mph if you want to overtake.

its a bit understeery, but the inside is nicely put together, and its basically honda mechanicals.

prob not a bad option for a good sized family motor on the cheap

atb

steve

Spunky, yes the kop variator is quite similar, uses ball bearings and conical discs if my memory serves me right?

Quite close to my heart this one as I designed, built and tested an electronically controlled infinitely variable mechanical transmission for my engineering degree thesis, sounds really high tech, well the way it worked was quite clever but it was used in a pretty simple agricultural application so not all that exciting!!

The variator I am on about is the Torotrak system, www.torotrak.com explains all re. the car transmission.

I did think of another application when I did my thesis in 1998-99 which I mentioned to Torotrak and heard nothing back, but strangely now this specific application is mentioned on their website, and that is an electronically controlled variable speed mechanical drive for a supercharger. Basically this would enable a fully mapped boost curve from a mechanically driven positive displacement supercharger, i.e. run high compressor rpm at low engine rpm and maintain the required compressor speed regardless of engine speed.

I recently discovered that a similar system was used on Harrier jump-jets (and other planes) to control alternator speed and maintain this as constant regardless of engine speed. It is also used on the new wind turbines sprouting up everywhere to maintain 50hz on the alternators in these.

The use in a supercharger drive is something I would love to experiment with (given time and money!!)

quote:

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Originally posted by NS Dev

I did think of another application when I did my thesis in 1998-99 which I mentioned to Torotrak and heard nothing back, but strangely now this specific application is mentioned on their website,

---

quote:

---

Originally posted by JoelP

quote:

---

Originally posted by stephen_gusterson
" i used to drive an omega "


thats the problem in a nutshell, isnt it? regardless of box...


atb

steve

---

1996, heated back seats, less the £2k. find a similar car like that though?

---

do you think that this one will stay outside of your house this time!

welcome back


steve

Long story steve. The sierra disappeared again (even though it was immobilised, courtesy of a hi-ab, reg no: G927PAU { wanted by police in respect of theft of motor vehicle, damage to motor vehicles, assault,etc & registered to an address that doesn't exist. Found by me & followed while police contacted & all they wanted me to do was ignore it!!!!!!!???.}. So I had to replace a car and so I replaced the wife 2.0i (pinto) ghia granada which still leaves me with a donor. Oh and Omega CDX's have thatcham catagory 1 alarm/immobilsers as standard.


enjoy.

...just found this thread!

I'll let you know

I have a Mazda6 with the tiptronic-style auto - no "clutch slipping" from the latest generation of electronic autos!

Under full noise it even lifts the throttle for up-changes.

The tiptronic mode holds the selected gear until you nudge it up or down (as long as you're in the safe rpm range!), but drops down to 1st when you stop. Also gives good engine braking on downshifts.

For you middie guys, a Honda V-TEC with the Accord 5-speed auto would be awesome!

Not so good for the rest of us, since one computer runs the engine and box and talks to the ABS and traction control

Well i'm new to this fourm and have just discovered this topic and as my build actually has an auto trans I find the topic intresting . I'm using a Toyota Ke 70 corrola trans coupled to a Nissan N16 engine . weight of the transmission is certianly an issue but as a lot of the preformance in these cars is about of the mark get up and go there may be gains for that in going auto . certianly conecting the engine and trans is simpler as is the shifter but I have been able to make my car with the tube across the front of the foot wells intactand that will ad to the chassis rigidity . any way time will tell how the car preforms in the real world on the road.
I have had an automatic sedan as our family car for some time and after about twenty years of manuals it is a joy to drive , sure the caracteristics are diferent to a manual and a lot of the percieved shortcomings of auto tranmisions are really down to the drivers not making the most of them and trying to drive them the same way as a manual .
best wishes
Iain

F1 gearboxes are sequential, and I think hydraulically operated (power assisted at any rate).

Mark

quote:

---

Originally posted by NS Dev
Spunky, yes the kop variator is quite similar, uses ball bearings and conical discs if my memory serves me right?

Quite close to my heart this one as I designed, built and tested an electronically controlled infinitely variable mechanical transmission for my engineering degree thesis, sounds really high tech, well the way it worked was quite clever but it was used in a pretty simple agricultural application so not all that exciting!!

The variator I am on about is the Torotrak system, www.torotrak.com explains all re. the car transmission.

I did think of another application when I did my thesis in 1998-99 which I mentioned to Torotrak and heard nothing back, but strangely now this specific application is mentioned on their website, and that is an electronically controlled variable speed mechanical drive for a supercharger. Basically this would enable a fully mapped boost curve from a mechanically driven positive displacement supercharger, i.e. run high compressor rpm at low engine rpm and maintain the required compressor speed regardless of engine speed.

I recently discovered that a similar system was used on Harrier jump-jets (and other planes) to control alternator speed and maintain this as constant regardless of engine speed. It is also used on the new wind turbines sprouting up everywhere to maintain 50hz on the alternators in these.

The use in a supercharger drive is something I would love to experiment with (given time and money!!)

---

Rotrex have tried in the past and the last iteration was too inefficient to be much use. Maybe they have come up with something that works now. Will be interesting to see