Sequential gearbox

[gino1]

Hia All,
Has anyone ever fitted a sequential gearbox in an Elan ?
If so what type ?
Thanks

Gino
Milano
italy

[GrUmPyBoDgEr]

Hi Gino,

no I haven't but I saw a Quaiffe sequential box based on the Ford/Elan box on display on their stand at the NEC racing car show a few years ago.

I don't think it would fit into an elan because the clutch operating system seemed to need a lot of space on the side of the box; if my memory serves me well!

Cheers
John

[CBUEB1771]

Hia All,
Has anyone ever fitted a sequential gearbox in an Elan ?
If so what type ?
Thanks

Gino
Milano
italy

Gino,
There have been several links to the Elan restoration project at Jay Leno's Garage website.
http://www.jaylenosgarage.com/cars/lotus/#item=215886
I am fairly certain he is installing a Quaife sequential gearbox. His team is fabricating modifications to move the gear lever forward. I would have thought the clutch actuation would be with a slave cylinder concentric to the input shaft.

[GrUmPyBoDgEr]

Hia All,
Has anyone ever fitted a sequential gearbox in an Elan ?
If so what type ?
Thanks

Gino
Milano
italy

Gino,
There have been several links to the Elan restoration project at Jay Leno's Garage website.
http://www.jaylenosgarage.com/cars/lotus/#item=215886
I am fairly certain he is installing a Quaife sequential gearbox. His team is fabricating modifications to move the gear lever forward. I would have thought the clutch actuation would be with a slave cylinder concentric to the input shaft.

Hi Russ,
yes that is well possible & more than likely but I got a bit mixed up with my description of the technology.

There appeared to be a relatively large "box" on the side of the gearbox which supplied the clutch gear change "signal" or whatever but in any case the clever bit of gubbins that does all of the gear change, clutch thinking and or mechanical actuation etc.

Cheers
John

[oldelanman]

Steve Broad who posts on here at times is fitting an Elite 6 speed sequential in his Cosworth project......

Photo from this thread....
elan-mods-f31/donor-speed-gearbox-possibility-t25526.html

[Pistacchio sprint 72]

Gino.... this is anarchy!!!

[CBUEB1771]

There appeared to be a relatively large "box" on the side of the gearbox which supplied the clutch gear change "signal" or whatever but in any case the clever bit of gubbins that does all of the gear change, clutch thinking and or mechanical actuation etc.

John,
It could be that Quaife is using a barrel selector system as was common in F1 a few years ago (maybe still is). The "box" you saw might house the barrel and its end of the selector forks.

[GrUmPyBoDgEr]

There appeared to be a relatively large "box" on the side of the gearbox which supplied the clutch gear change "signal" or whatever but in any case the clever bit of gubbins that does all of the gear change, clutch thinking and or mechanical actuation etc.

John,
It could be that Quaife is using a barrel selector system as was common in F1 a few years ago (maybe still is). The "box" you saw might house the barrel and its end of the selector forks.

Hi Russ,

yes it definitely utilized a barrel selector or what I would describe as a cylindrical cam, not being so up to speed on the technology.
It being some time ago I don't remember properly but I think that the barrel selector was in the gearbox casing & the back & forth motion gear lever slotted into it; the other box of bits (whatever it did) was fastened to the side of the casing. In any case I don't think that it would fit in the Elan's backbone without modifications.
Strangely I was only thinking this afternoon, why bother?
The old Ford/Lotus 4 speed gearbox really set the standard way back when & even today is still pretty damned good as fat as smoothness & positivity in gear change.
I think that the attraction for me in the Quaiffe sequential box was that it had 5 or 6 gears!

But I ask this question; what are the advantages of a sequential change?
Does sequential automatically mean "clutch-less" gear changes i.e. no manual clutch at all?
I don't think so with such basic designs like the Quaiffe

Regardless of use e.g. road or competition isn't the possibility to change, let's say from 4th down to 2nd without having to go through 3rd a big plus?

I can imagine that back in the day the drivers swooned over that facility.

Lots of food for thought arising from a question about who makes the thingies
By the way this is a neutral emoticon which raises the question about finding that so special gear with a sequential box where my H shaped gear change has neutrals everywhere

Cheers
John

[CBUEB1771]

John,
Cylindrical cam is a much better descriptor, somehow barrel came into common use. The sequential boxes came into favor with the advent of semiautomatic "paddle" gear change and the ability to operate the concentric cam with a single actuator, just one rotary device. You of course need two actuators for the good old H-pattern.
Russ

[msd1107]

Cylindrical cam sequential shift gearboxes have been around for at least 60 years.

Because of the usual shift mechanism, you can only go sequentially from gear to gear, not skip gears. Some gearboxes allow you to select neutral from any gear rather than go through the gears to the neutral usually located between 1st and 2nd (or reverse and 1st).

You can usually shift these either using the clutch or not. If not, usually a momentary ignition cutout or throttle lift is necessary to rotate the shift drum and disengage one set of engagement dogs and rotate the drum to select the next gears dogs.

I do not know of any sequential shift gearboxes with synchromesh, so you have to be a bit of a masochist to drive one on the street, although motorcyclists do it all the time.

Note that the original Lotus "queerbox" was sequential shift also, but did not use a cylindrical cam.

David

1968 36/7988

[GrUmPyBoDgEr]

Thanks guys, with all of that fresh information fully digested I will be able to talk sequential gear changes with the best of 'em

Cheers & thanks really; an interesting interlude.
John

[elansprint71]

If Gino's query is connected to his other thread re: Modsports; I'm pretty sure that a sequential gearbox would not be acceptable in a revived Modsports class.
Beats me what Leno is up to with that car; it will never be accepted to race in any category, so why did he not just scratch-build whatever is in his head, rather than wrecking an Elan?

[cabc26b]

Gino,

The one I like is collaboration between TRE ( taylor not toyota) & elite , it uses Staffs, Hewland case/guts and Elite ( not lotus) parts to convert to inline . you end up with a compact 4, or five speed box using Hewland MK gears so you have lots of choices , shifter can be configured for h-pattern or sequential . its light a 40 Lbs ( under 20 kilos) I think they have it worked up for the ford bell housing as well but not 100% sure here.

John , FWIW , you can clutch-less a shift a h pattern Hewland MK box ( Hewland also offer sequential on the old FT200 design ) , the Quaife gear set for the 2000E box was a little more agricultural so I never really tried to clutch-less shift it ( not being critical here, its a good thing because you can't change the gears in situ like you would a trans axle)

I recall seeing the barrel/drum selector in a old ( 60's) ZF racing trans axle apart on the bench at the shop one time - looked like a PITA to work on.

George

(if my current vintage race car project get's classed with the cars that 20years newer with motors 2-3x the displacement like the last one, i'm putting on of these in )

[GrUmPyBoDgEr]

I may have written something confusing when I wrote clutch less gear change.
I didn't mean the ability to change gear without using the clutch but that there would be no clutch pedal in the car as in the modern flappy paddle & or back/forth gear lever/stick.

Cheers
John

[msd1107]

You can change gear in any manual transmission without using the clutch, I have done it many times in my Elan when the clutch slave cylinder fails. (My mechanic was 30 miles away through mainly LA city streets.)

Clutchless gear changing on a synchromesh gearbox can be quite slow in order to preserve the synchros. It can be lightning fast on a dog gearbox, since only a slight decrease in power is necessary in order to pull the dogs out of engagement of one gear and the rotational speed difference guides the dogs into engagement in the next gear.

However, dog clutch engagement usually is noisy and jerky on a street car, not so much on a motorcycle. So if you are thinking of going with a sequential dog box for the street, try to drive a car so equipped in a street equivalent mode, even if it is on a track.

F1 paddle shift gearboxes shift under sophisticated CPU control for seamless shifting.

David
1968 36/7988