T56 Shift Mods

[HI PSI]

So will still need clutch for upshifting then? Most boxes wont even pull out of gear under load. Many moons a go a mate who works at HSV had a guy come in with a VT LS T56 combo saying it was popping out of third. WOT 3rd gear and the apprentice in the passanger seat couldn't yank it out of gear under load let alone popping out. Turns out the owner was just ohmo but I will admit the 2nd to 3rd change on my VX was pretty ordaniry with the stock shifter.

Sooooo, not to challenge your judgment and im a big fan of your build....but whats the point without the box built to suit?

As I am running a Haltec, I will be able to have a gear cut. This combined with a pressure switch on the gear knob, mightallow a synchro box to up shift clutchlessly. Thoughts anyone?

[barnz]

Not a chance the revs will need need to drop for it to go into the next gear without a clutch.

Not apples for apples but I drive my work ute all the time without a clutch coz my farked knee gets sore after a while. I also just tried all of this whilst on my way to work.

Wont come out of gear under load, was trying to pull it out of 3rd with everything I had, at about 50% throttle it would but still difficult. Revs need to fall to pop into the next gear, the larger your rev range and more spread across the gears the longer that will take, it cant be forced either, you can put all the pressure on it you want it will pop in when its ready. Throttle blip required on a downshift, much more tricky than upshifting, will grind bad if you dont get the throttle blip right. In my experience most syncro boxes behave the same.

What I do think though is with some practice, the right clutch like a button and some torque reduction setup so you can hold it WOT it will be alot quicker than the H pattern setup.

Edited 08/12/15 09:42 PM by barnz

[JETURBO]

In fact Brad is correct Barnz as clutchless upshifts are 100% doable and flawless with the T56

Not my area of expertise but the ones in the know have it sussed and it sounds like brad has been informed on the process to do it

I can see what brad is contemplating as a very fast combo coming up

[k31th]

Not a chance the revs will need need to drop for it to go into the next gear without a clutch.

I think that's where you're wrong. If you can cut the spark at the right time (via a switch setup as described above), the load comes off the gear and the selector can be pulled out and slotted into the next gear when under "load" conditions (as long as the revs match the next gear's step-down position, in terms of revs and gear teeth positioning). Having "straight-cut" or "dog-engagement" gears helps with this.

How else do you think cars like v8 supercars do it?

[Ralph Wiggum]

Totally doable, but your clutch needs to be up to the task.

A strain gauge on gear stick feeding force back to the Haltech should allow you to set the ign cut based on how hard you grab the shit lever.

Ihatetoads has it working on his ba using an external controller and some tuning trickery.

[barnz]

Like I said not apples for apples and far from my area either just my experience with clutchless shifting syncro boxes. However it would explain why a sequential shifter is even avalible for the t56 and if the switch is so close enough to be made before it actually shifts I could see how it might work. Dont syncros need to spin up a bit though? Very interested to see how this goes.

[barnz]

I think that's where you're wrong. If you can cut the spark at the right time (via a switch setup as described above), the load comes off the gear and the selector can be pulled out and slotted into the next gear when under "load" conditions (as long as the revs match the next gear's step-down position, in terms of revs and gear teeth positioning). Having "straight-cut" or "dog-engagement" gears helps with this.

How else do you think cars like v8 supercars do it?

Yeah......a Albins trans built for the purpose of racing is quite different to a oem t56...im well aware of how a sequential box works lol...and you have basically just reiterated what I said about it not wanting to come out of gear under load.. Its a very interesting topic im keen to know more about, sequential t56/tr6060 sounds much more fun than a ZF.

Also taking the load off is fine but the revs arent gonna match in a split second from say 6krpm to 4k where it needs to be for the next gear for example which is the part I dont get and am interested to know how its overcome.

Edited 08/12/15 10:24 PM by barnz

[Ralph Wiggum]

Shifts aren't made under load. No spark = no bang = no load.

[k31th]

Yeah......a Albins trans built for the purpose of racing is quite different to a oem t56...im well aware of how a sequential box works lol...and you have basically just reiterated what I said about it not wanting to come out of gear under load.. Its a very interesting topic im keen to know more about, sequential t56/tr6060 sounds much more fun than a ZF.

WOT shifting is just a matter of setting the 'box up for it. The T56 (and any other manual with room for a sequential shifter or ignition-cut-switchable setup) can be setup to do it. In stock form, of course it's much more difficult.

The simple fact is the Albins is not just a dog-engagement gearbox, but also a transaxle. That's the only part that makes it a "specialist" piece of kit. The rest is just mechanical sequential gear selection and switches on the gear selector to cut ignition just long enough to slot between gears.

Edited 08/12/15 10:24 PM by k31th

[barnz]

I got no idea what your getting at keif lol....Albins also make non transaxle boxes. I know how a purpose built sequential box works. None of what you have said explains how the sycromesh is overcome to allow it to slot straight into the next gear. Put it this way if it was so simple to convert a sycro box, why are sequential boxes engineered differently, longevity? Strength? Syncros just arent ideal for the application?

Sorry if this is getting long in the tooth jet lol. Its just interesting..infact probably the most interesting topic I have seen on here in a while lol..

Edited 08/12/15 10:35 PM by barnz