Sequential Transaxle

Started by MD, October 25, 2015, 08:25:00 PM

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MD

Anybody seen, smelled, sniffed or heard of a sequential conversion to the Alfetta transaxle or an equivalent swap in?
Transaxle Alfas Haul More Arse.

Current Fleet
Alfetta GTV6 3.0
Alfetta GTV Twin Spark supercharged racer
75 1.8L supercharged racer

Past Fleet
Alfa GT 3.2V6
Alfetta GTV 2.0
Giulia Super 2.0
Berlina 2.0

Mrme4u

I only know about a straight cut gears coloti set.
Alfa was using Xtrac racing transacles on their race cars not the road transmission

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MD

SNAPPIN' DUCKS !!!!!

They let Mike out of Jail for 5 minutes and now look what he's up to....AMAZING ! Onya Mike !!
Transaxle Alfas Haul More Arse.

Current Fleet
Alfetta GTV6 3.0
Alfetta GTV Twin Spark supercharged racer
75 1.8L supercharged racer

Past Fleet
Alfa GT 3.2V6
Alfetta GTV 2.0
Giulia Super 2.0
Berlina 2.0

Mrme4u

What I have is this

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Darryl

Quote from: Mrme4u on October 29, 2015, 09:37:58 PM
What I have is this

Do we get a hint? What is that casing to the right of the gearset?

MD

Well to stay on topic, a set of custom clutch mounts, rose jointed watts links and lightened gear set is all helpful towards improving general performance but to be fair, these things in themselves make no specific contribution to a sequential transaxle.
Transaxle Alfas Haul More Arse.

Current Fleet
Alfetta GTV6 3.0
Alfetta GTV Twin Spark supercharged racer
75 1.8L supercharged racer

Past Fleet
Alfa GT 3.2V6
Alfetta GTV 2.0
Giulia Super 2.0
Berlina 2.0

Mrme4u

Quote from: Darryl on October 30, 2015, 05:58:35 PM
Quote from: Mrme4u on October 29, 2015, 09:37:58 PM
What I have is this

Do we get a hint? What is that casing to the right of the gearset?
The casing next to the gear set is a transmission of a Bertone GTV I was also working on

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105gta

What exactly do you want to know?
There is no kit specifically for the Alfa transaxle but a few that could be adapted.
To make it truly successful there are a lot of internal mods required to the trans to get the most out of a sequential shifter.
As far as the shifter itself, that's the easy part. It's a matter of what your end goal and expected outcome is.
Ben
1967 Giulia Sprint GT Veloce (WIP)
1985 GTV6 (WIP)

MD

Couple of simple things really:-

Get rid of the shift gate larger than the Grand Canyon
Reduce the shift throw just short of a Dennis Lilly leg by.

With a lightened gear set and other mods, the internal pace of the box shift is fine.

With all the paddle shift mechanisms around, I also wondered if there would be a way to delete the entire mechanical linkages and couple that to the sequential shifter.

...brain in neutral and mentally doodling over coffee aroma here.  ::)
BTW, It's only coffee instead of Champers because I couldn't manage to get a day off for my horse pulling the Milk Cart to enter it in the Melbourne Cup. Sad really.
Transaxle Alfas Haul More Arse.

Current Fleet
Alfetta GTV6 3.0
Alfetta GTV Twin Spark supercharged racer
75 1.8L supercharged racer

Past Fleet
Alfa GT 3.2V6
Alfetta GTV 2.0
Giulia Super 2.0
Berlina 2.0

105gta

The simple solution would be a cable system adapted from the kits available for nissans etc.. But that won't give you paddle shift. My research has ended up concluding the most suitable for the Alfa trans is an external drum type mechanism, if you want paddle shift then an air shifter is far more sympathetic to the internals than either an electric or hydraulic system. I originally considered hydraulic but I don't feel the trans will cope very well internally.
To maximize things you really need a lightning fast shift, probably alfas biggest drawback. Modifications to the internals of the box can help this, lightening of gears, modified synchro teeth and most importantly spacing of the ratios! (Another sore point) but it is all achievable if you want to put the time and effort into it.
1967 Giulia Sprint GT Veloce (WIP)
1985 GTV6 (WIP)

Duk

#11
I really, really don't see any point in trying to get a synchromesh based gearbox to try and be any sort of sequential shift gearbox.
There are aftermarket electric paddle shift set ups for car like the C6 Corvettes. But really speaking, the shift time is entirely determined by the ability of the gearbox to move from 1 gear to the next. You'd also need to implement some sort flat shift torque reduction so that it can be done without lifting the throttle.
https://www.youtube.com/watch?v=wQDP2YKOW8A : Andy Wyatt of Adaptronic fame.

PPG in Adelaide have apparently converted various other gearboxes to sequential shift arangements, but I'd bet a carton of Coopers that the initial criteria was for dog ring engagement first.
The Daily: Jumped Up Taxi (BF F6 Typhoon). Oh the torque! ;)
The Slightly More Imediate Project: Supercharged Toyota MR2.
The Long Standing Conundrum: 1990 75 V6 (Potenziata)............. What to do, what to do???

105gta

There is no problem using synchromesh and sequential shift. Most modern cars have automated shift and synchromesh which work rather quickly. The issue is a combination of our under developed synchro, poor ratio's available and the physical distance the hubs have to move.
All fixable but not easily for most.
As Duk has agreed there are electric kits available for other models but they are barely somewhat successful but I doubt on our trans. (Nor sympathetic). But dog engagement is available if you're that way inclined
Alfa hasn't performed any development on the synchro since the 60's on our trans but Porsche continued forward. ;) It is possible to modify the system for better, faster and more reliable shifts following some of Porsche's ideas.
Flat shift has been included in most half respectable ecu's for atleast 10 years now but I think if you're at the point of thinking about paddle shifts then flat shift is probably already being used.
The Alfa transaxle is up to the job but not as it stands now. It's an ancient design and behind the times. Fortunately the biggest obstacle is spare time and determination.  (And  shitballers on the internet)
1967 Giulia Sprint GT Veloce (WIP)
1985 GTV6 (WIP)

Duk

Quote from: 105gta on November 08, 2015, 11:08:39 PM
There is no problem using synchromesh and sequential shift. Most modern cars have automated shift and synchromesh which work rather quickly.


You've lost me there. What purely mechanical, not some jumped up automatic or dual clutch gearboxes, are out there, that are sequential shift?
The Daily: Jumped Up Taxi (BF F6 Typhoon). Oh the torque! ;)
The Slightly More Imediate Project: Supercharged Toyota MR2.
The Long Standing Conundrum: 1990 75 V6 (Potenziata)............. What to do, what to do???

Duk

Quote from: MD on November 05, 2015, 08:43:13 AM

Get rid of the shift gate larger than the Grand Canyon
Reduce the shift throw just short of a Dennis Lilly leg by.

With a lightened gear set and other mods, the internal pace of the box shift is fine.


MD, if you're happy with the shift speeds of the 'box, why not make a different linkage mechanism?
I mean, the amount the input selector shaft has to be moved to select a gate or a gear isn't actually that much. So if you're not happy with the amount you have to move the actual lever, maybe the answer is closer to you mitt than your butt.
The Daily: Jumped Up Taxi (BF F6 Typhoon). Oh the torque! ;)
The Slightly More Imediate Project: Supercharged Toyota MR2.
The Long Standing Conundrum: 1990 75 V6 (Potenziata)............. What to do, what to do???