Lift on upshift on early semi auto boxes in F1?

All that has to do with the power train, gearbox, clutch, fuels and lubricants, etc. Generally the mechanical side of Formula One.
gold333
7
Joined: 16 May 2011, 02:59

Lift on upshift on early semi auto boxes in F1?

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Can anyone verify if the earliest generation semi auto gearboxes with gear change paddles on the steering wheel:(Ferrari 639, 640, etc.) had the Magnetti Marelli electronics setup synchronised so the throttle would automatically cut during upshifts? Or was the driver advised to lift the throttle on upshifts himself?

In this video it sounds A LOT like the driver is not lifting on upshifts, yet at the same time it sounds as if the car is not liking it very much. (at 3m14s)



This is quite a specific question and would really require someone very familiar with late 80's, early 90's F1 semi automatic transmission technology.
F1 car width now 2.0m (same as 1993-1997). Lets go crazy and bring the 2.2m cars back (<1992).

Jolle
132
Joined: 29 Jan 2014, 22:58
Location: Dordrecht

Re: Lift on upshift on early semi auto boxes in F1?

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gold333 wrote:
28 Apr 2020, 22:38
Can anyone verify if the earliest generation semi auto gearboxes with gear change paddles on the steering wheel:(Ferrari 639, 640, etc.) had the Magnetti Marelli electronics setup synchronised so the throttle would automatically cut during upshifts? Or was the driver advised to lift the throttle on upshifts himself?

In this video it sounds A LOT like the driver is not lifting on upshifts, yet at the same time it sounds as if the car is not liking it very much. (at 3m14s)



This is quite a specific question and would really require someone very familiar with late 80's, early 90's F1 semi automatic transmission technology.
Just a very simple ignition cut during shifts. Nothing fancy.

Tommy Cookers
617
Joined: 17 Feb 2012, 16:55

Re: Lift on upshift on early semi auto boxes in F1?

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Doug Nye's 1966-91 book says (in feature headed 'Semi-Automatic Transmissions') these 'boxes gearchanges ....
'would only interrupt the application of engine power or over-run torque for the most fleeting of milli-second time periods'

and that John Barnard said ....
'right from the beginning I felt the possibility of going full auto must be there. In conjunction with Bosch we'd run an electronic throttle at McLaren in 1985, but only in practice. It used a servo motor on the engine, a rotary encoder on the throttle and just an electrical wire connecting the foot pedal and the engine. With that coupled to a gearbox control and operating the clutch fully hydraulically, then I couldn't see why you couldn't make the fully automatic car'.

gruntguru
563
Joined: 21 Feb 2009, 07:43

Re: Lift on upshift on early semi auto boxes in F1?

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In the video, the gear disengages slightly before the ignition cut - you can hear the blip in revs. Not ideal.
je suis charlie

saviour stivala
51
Joined: 25 Apr 2018, 12:54

Re: Lift on upshift on early semi auto boxes in F1?

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‘Gear disengage (slightly or not) before throttle blip’.
On any ‘manual’ gearbox being in-gear and under power. It is not possible for the engaged gear to be made to even start to disengage unless power is removed/reduced – the first movement of throttle blip while under power being throttle lift. (With the advent of electronics throttle blipping to aid gear change is made/effected by means of ignition-cut). Which means removed/reduced power. To prove what I am saying, one can try to disengage a gear while driving his road car with stick-shift gearbox while under power. To this day in formula 1 throttle blip to aid gear change is still used. even so sequential seamless gearboxes are used, (seamless:- where one gear is engaged while the next in sequence 'up or down-shift' is also pre-engaged). but today the throttle blip is used mainly to help disengage the out-going dog-clutch,

gruntguru
563
Joined: 21 Feb 2009, 07:43

Re: Lift on upshift on early semi auto boxes in F1?

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What happens in the video is not a throttle blip. I am talking about a full-throttle upshift. The ignition cut does not begin soon enough to avoid a brief increase in revs.
je suis charlie

Tommy Cookers
617
Joined: 17 Feb 2012, 16:55

Re: Lift on upshift on early semi auto boxes in F1?

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saviour stivala wrote:
29 Apr 2020, 06:52
.... On any ‘manual’ gearbox being in-gear and under power. It is not possible for the engaged gear to be made to even start to disengage unless power is removed/reduced ....
what's 'any' manual gearbox ?

race cars and all motorcycles have so-called 'dog 'boxes' - anything is possible in the heat of the moment
road cars don't have these
afaik

saviour stivala
51
Joined: 25 Apr 2018, 12:54

Re: Lift on upshift on early semi auto boxes in F1?

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Drive your car in any gear with throttle to the floor and try as hard as you can to force disengagement of gear.

Jolle
132
Joined: 29 Jan 2014, 22:58
Location: Dordrecht

Re: Lift on upshift on early semi auto boxes in F1?

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saviour stivala wrote:
29 Apr 2020, 12:32
Drive your car in any gear with throttle to the floor and try as hard as you can to force disengagement of gear.
Racing gearboxes and road gear boxes are not the same. The straight teeth and the missing sync rings will, with a bit of force, slip you out or gear without any problem.

gruntguru
563
Joined: 21 Feb 2009, 07:43

Re: Lift on upshift on early semi auto boxes in F1?

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It is common practice to modify motorcycle dog boxes for full throttle shifting without any torque reduction (ie no ignition or fuel cut). Once modified (mainly heavily bevelled leading edges on dogs) the box can be upshifted under full load with a heavy stomp on the gear-lever.
je suis charlie

CMSMJ1
Moderator
Joined: 25 Sep 2007, 10:51
Location: Chesterfield, United Kingdom

Re: Lift on upshift on early semi auto boxes in F1?

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saviour stivala wrote:
29 Apr 2020, 12:32
Drive your car in any gear with throttle to the floor and try as hard as you can to force disengagement of gear.
As was said 0 straight cut gears and dogs will allow a forced change. It's not nice but it can be done but use of an ignition cut allows for the gears to go in

I would imagine the technology for these 1989 Ferrari changes was similar to a friends motorbike system as he has limited movement in the feet and uses buttons to change gear. A hydraulic ram shifts the gears and a standard quickshifter cuts the ignition 60ms to allow for the change.
IMPERATOR REX ANGLORUM

saviour stivala
51
Joined: 25 Apr 2018, 12:54

Re: Lift on upshift on early semi auto boxes in F1?

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Dog-clutch engagement when upshifting under full load (no throttle lift/ignition cut) with brute force is possible.
(Force is applied to the shift-sleeve and the sliding dog starts to move towards the gear wheel containing the other half of the dog-clutch, dog-to-dog contact occurs with high impact. The force will try to stop the sliding dog by consuming the motion energy. As a consequence, the face contact between dog clutches are slipping each other. When the mating cut-out and projection faces each other the engagement will be completed).
The dog-clutch cut-out edges are normally rounded or sometimes bevelled to facilitates engagement, that is apart from how big a clearance is opted for between the male and female engaged projections. The heavier the edge is bevelled the more the reduced load carrying engaged faces will be.
But the problem of shifting gear (up or down shift) without throttle lift/blip/ ignition cut is not dog-clutch engagement, but dog-clutch disengagement which is needed when shifting power from one gear ratio to another. Dog-disengagement while under power with no lift/blip or ignition cut is near impossible.

saviour stivala
51
Joined: 25 Apr 2018, 12:54

Re: Lift on upshift on early semi auto boxes in F1?

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Having said all that in the above post as regards the needs of shifting gears by use of dog-clutch moved by a selector fork actuated by a shift-barrel. Most probably all of the modern day seamless-shift gearboxes in use in F1 have progressed from a two shift-barrel with even and odd number gear selection controlled separately, to a single shift barrel use and further developed to do away with dog-clutch and shift fork located between gears. And putting the shifting components inside the main shaft and so aligning the ratio gears without any gap in-between.

gold333
7
Joined: 16 May 2011, 02:59

Re: Lift on upshift on early semi auto boxes in F1?

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Thanks for the replies but this thread has confused me more than it has helped.

I’m confused by the sometimes contrasting replies.

So to be clear: did early semi automatic gearboxes in F1 (say a 1991 Ferrari 642 or 643) require a lift on upshift or was it programmed in the ECU?
F1 car width now 2.0m (same as 1993-1997). Lets go crazy and bring the 2.2m cars back (<1992).

Jolle
132
Joined: 29 Jan 2014, 22:58
Location: Dordrecht

Re: Lift on upshift on early semi auto boxes in F1?

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gold333 wrote:
02 May 2020, 07:46
Thanks for the replies but this thread has confused me more than it has helped.

I’m confused by the sometimes contrasting replies.

So to be clear: did early semi automatic gearboxes in F1 (say a 1991 Ferrari 642 or 643) require a lift on upshift or was it programmed in the ECU?
It was programmed in the ECU. Driver just kept his foot down