BXProject

docchevron132 · Post by **docchevron132** » 25 Dec 2007

A while ago I thought about building an autobox for my valver, since my left leg is sometimes a bit wank.
I dismissed the idea as I like the manual box and I've always managed.

Then dad got ELF, Ian Fearns old 8V GTi auto.
And I started thinking again. Wouldn't it look cool with a full P2 bodykit and a D6C lump?...
Haven't quite talked dad into it....yet..
But dad MUST have an auto, so it would have to be a 16v auto.
Then Mickey made me think about it again today..

The box for the TD cost Â£3500, not including the flexiplate which I had specially made, and the hoses, which were either modded, or made.

I planned out the valvechest arrangement for a D6C ages ago, and I think I've got the ratio's for the epicyclic sussed.
The flexiplate would have to be another one off special to accomodate the cut outs for the crank angle sensor, this I know already as I have a flexiplate for an 8v on the floor, and it aint the same as the flywheel of a valver.
The next issue would be getting the weighting right, considering the flexiplate is very light, but the torque converter is a good sight heavier than the valver flywheel.
Non the less, I still think I might have a go at this, if not for Mickey, then maybe for dad if I can twist his arm, if not, just for a project really, since it aint been done before, and I get bored doing samey stuff....

Time to ring ZF again I think....

David · Post by **David** » 26 Dec 2007

TBH the ideal thing I think you need for this arrangement is something similar to a C-matic box like fitted to an early CX or GSA

Keep the manual shift, but fit a torque converter with a lock-up clutch. That way you get all the benefit of a torque converter for pulling away and the lack of a clutch pedal, but at cruising speeds you get the efficiency of a manual box with a lock-up clutch.

win-win.

Stinkwheel(Matt) · Post by **Stinkwheel(Matt)** » 26 Dec 2007

anyone ever encounter the centrifugal clutch as fitted to some 2CV's dyanes amis etc in the 60's and 70's??

Basically the flyswheel held a normal clutch but also had like a break band type arrangement that aloowed you to pull away in first and second and also break to a stop in the same gears, without the use of of the clutch pedal. I had a dyane with it on. A brilliant and very helpful system. Im afraid i've explained it a bit crap, but if you want more idea then google 'citroen trafficlutch'

Terry · Post by **Terry** » 26 Dec 2007

Stinkwheel(Matt) wrote:anyone ever encounter the centrifugal clutch as fitted to some 2CV's dyanes amis etc in the 60's and 70's??...............

I had one one my first ever ['71] Dyane.
It was a "Centrifugal Clutch" and operated like a pair of brake shoes ......the "shoes" opened up at over 1000rpm and contacted the drum,thus giving drive ...........they closed at under 1000 which had the effect of disengaging the clutch.

It was brilliant for hill starts ........being totally impossible to stall the engine [the clutch disengaged at just less than 1000rpm] ..........very handy for a learner driver [as I was then]
Brilliant in town too,you could just pull away in 1st or 2nd gear without using the clutch.
On the downside.............if you were going downhill and changed gear into a lower one [say from 3rd to 2nd] you'd lose the engine revs,the clutch would disengeage and it would kick in and attempt to throw you through the front windscreen when the revs hit 1000rpm.
If you parked up and switched the engine off after revving it there was a bloody great flywheel spinning which would make the car lurch forward if you left it in gear as soon as your foot was removed fron the clutch....I believe the dent is still in the garage door of my old house! .....unless you'd left it in reverse,in which case the door would smack you in the face as you opened it to get out of the car.
Bump starting,if the battery was flat was a complete waste of time [no clutch = no drive to the engine]

T.

docchevron132 · Post by **docchevron132** » 27 Dec 2007

David wrote:TBH the ideal thing I think you need for this arrangement is something similar to a C-matic box like fitted to an early CX or GSA

Keep the manual shift, but fit a torque converter with a lock-up clutch. That way you get all the benefit of a torque converter for pulling away and the lack of a clutch pedal, but at cruising speeds you get the efficiency of a manual box with a lock-up clutch.

win-win.

True, but I have spare ZF auto casings, and a C-Matic bix would need designing from scratch I think..

The ZF on BX's had 75% lock up in third and full lock up on top anyway.
If I could make it fit I'd wham a ZF 5HP500 in it, half gears full lock on every gear, 5 ratio's, and a bloody clever torque converter with vary veins!
Alas, it's huge and weighs ALOT....

Stinkwheel(Matt) · Post by **Stinkwheel(Matt)** » 27 Dec 2007

Thats the wording i was trying to think of Terry...........'centifugal drum' is exactly it

I took it apart on my dyane just to see how it worked.

And i also did the foot off clutch and run into the car in front when you stop trick, its like a jet engine spooling down when you turn off, very cool.

Way2go · Post by **Way2go** » 27 Dec 2007

Stinkwheel(Matt) wrote:Thats the wording i was trying to think of Terry...........'centifugal drum' is exactly it
.

Sounds like the same idea as fitted to "Suffolk" cylinder petrol lawnmowers. The centrifugal clutch is fitted on the engine output shaft. When the throttle is backed off to tick over, the cylinder & drive disengage.

Terry · Post by **Terry** » 27 Dec 2007

Stinkwheel(Matt) wrote:Thats the wording i was trying to think of Terry...........'centifugal drum' is exactly it

I took it apart on my dyane just to see how it worked.

Presumably,the Honda 50/70/90 "step-thru" works the same

One of those 'bikes was the first Jap [wrong sided gearchange] 'bike I ever rode.........I'd always been used to R/H gearchanges and real clutches

The bloke who sold it to me said ............"Dont put it in gear while its revving"
Like the stupid young cnut I was then ........I rode it home........and then I did

......just to find out why I should'nt

...and what would happen if I did

I think I still have the scar on my knee.

I've never had to take one to bits though........so I've no idea how they work.
T.

stu · Post by **stu** » 31 Dec 2007

David speaks the truth. C-Matic iz teh roxx0rz.

Philhod · Post by **Philhod** » 31 Dec 2007

The box you are looking at using is an excellent box, but as you say it`s an effing big lump!!!The cx route looks a better way to go

Have you thought about having a look at the new Citroen sequential boxes, to see if there is anything suitable. You don`t need the paddles you can use a "gearshift" in place of your "normal one"

I had one on my late 70`s Opel Manta mk2. After I had serviced it and cleaned the valve block out, it was superb

docchevron132 · Post by **docchevron132** » 01 Jan 2008

Ooh, hadn't thought about sequential boxes..
That could be quite good with the paddles!

Philhod · Post by **Philhod** » 01 Jan 2008

Not sure which one would be best

.....

Now they have fitted the latest version to the 140 bhp 2L turbodiesel, torque wise it will cope admirably methinks

It could be a lot cheaper too coz it won`t be too long before some prat drapes one round a tree for you

On another note I`m now back in the country and more or less back together

That "harmless" Aquavit was a bit of a bugger. You didn`t get any warning, just a sudden feeling of slipping away.

Laughed my bollocks off when I read Rachael`s finish to that post

The paddles are ok if you have a sitting up driving position. If you like to err lie back a bit the stick is the one to go for

docchevron132 · Post by **docchevron132** » 02 Jan 2008

Ah, welcome back to blighty mate!
Drink, work of the devil I tells ya, never touch the stuff myself of course......

Good point about the box... I like to recline whilst driving I have to say, and maybe having paddles would take something away from the BXness of the interior....
HHmm.... more to think about..

David · Post by **David** » 02 Jan 2008

how about using an LHM-type slave cylinder on a manual gearbox clutch release, and then driving it with a modified dosieur valve with reduced pressure feedback? That would mean minimal movement of your left foot, and a very "easy" clutch to hold in. Essentially a "power assisted" clutch.

Only drawback I can see is that you can't release the clutch without the engine running, which could be a pain for something like bump-starting the car.

Might take a while to learn how to do smooth pull-aways too....

Post by **Vanny** » 02 Jan 2008

David wrote:Only drawback I can see is that you can't release the clutch without the engine running, ....

makes for one hell of a theft deterant though! A mate has a landy with a mechlock that cuts the hydraulic clutch out of circuit, pretty much imobolising the bugger, and its worked, twice now!

docchevron132 · Post by **docchevron132** » 02 Jan 2008

I've thought about using the hydraulics to power the clutch before.
Still think thats a good idea too, but dad's left leg is fubar so I'm not sure how he'd get on with it, especially since it would require a fairly deft touch..

Although I'm not actually sure he wants ELF to have a D6C, but I WILL talk him into it eventually!

Philhod · Post by **Philhod** » 02 Jan 2008

Most of the dosier valves I`ve come across have been on or off affairs
Perhaps a force pilot solenoid valve with close muting might be an alternative.
There is a German company brochure knocking about here somewhere
offering miniature dosiers with "digital operaional adjustment" if my Deutsch is any good but I can`t find it

if I can remember their name
you can av a look on the net for techy explanations

Cant find the brochure but I think the company is
ww.ventiltechnik.de

Brill idea by the way David

docchevron132 · Post by **docchevron132** » 02 Jan 2008

If it's german though, how would it get on with the french?
Would it have a hissy fit mid operation and march into Poland?

Post by **Vanny** » 02 Jan 2008

what would be the point in going to poland? Theres no one there, they are are in the uk!

docchevron132 · Post by **docchevron132** » 02 Jan 2008

Easy phyrric victory though eh!

See, Hitler should have waited a few years, domination would have been much easier!
March to Poland, find sign saying "We have all gone to the UK, please close the door on your way out"..
Jobbed.

It got me thinking....