T56 Shift Mods

[k31th]

straight cut gears don't need synchronizing mesh.

[barnz]

Are t56's straight cut?

[JETURBO]

Boggles the mind a bit but yes it can happen and I believe Brad's info source is leading him in the right direction

I had a bit of a pow wow with someone yesterday and they believe that sequential style shifters in the past have been nothing but trouble but believes the S1 is a good looking bit of kit and the functionality is completely there

The connection of a strain gauge is the kicker as luke has mentioned and will be keen to see how it all pans out for Brad

One concern was the boxes strength at the power levels brad will be at and the 4th gear set is the weak link in the early T56's but anything pumping upwards of 1000hp into anything is going to be stressed hard

PPG do a full dog box T56 that's about 15k but is one sweet cog swopper if all else fails

[JETURBO]

Only reverse gears are normally straight cut

Everything else helical cut

[k31th]

Are t56's straight cut?

Not in stock form, no.

I know how a purpose built sequential box works.

It seems as though you don't...

None of what you have said explains how the sycromesh is overcome to allow it to slot straight into the next gear.

Ignition/Spark cut assists with the low load required to put a gear into place. If the gears line up (correct revs to match next gear positioning) then the 'mesh is NOT required. The mesh only assists in lining up drive gears to ratio gears.

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?

Higher torque/horsepower applications require stronger components. Dog-engagement is better than replacing burnt/broken 'mesh components. Synchro-mesh applications are just not required (and only get in the way) for the applications where sequential and WOT shifting are required.

It is certainly not simple (nor cheap) to convert a synchro 'box to a dog-engagement style box (straight-cut or helical cut, depending on manufacturer gear-style and terminology)

[barnz]

Wow ok.....well pelican since your such an expert on the subject perhaps you could explain how the rings in a dog box work which you have completley failed to mention. Also a H pattern box can run dogs so really has nothing to do with the shifter setup/arrangement. 6spd h pattern holinger the v8sc used to run is a good example. Could you also explain what is special about the t56 that in stock form allows it to be shifted pretty much instantaneously like a dog which is what im trying to UNDERSTAND not debate. We are talking about making a completley stock t56 do this with the only additions being the shifter and haltech.

K go.

[barnz]

Only reverse gears are normally straight cut

Everything else helical cut

Yeah I know, it would be the quietest straight cut box ever if it was lol. Just trying to get keif to explain to us exactly how its possible rather than random facts that may be true but seem irrelevant...

Cmon keify that's more than enough time to google some sh*t

Edited 08/12/15 11:17 PM by barnz

[k31th]

Wow ok.....well pelican since your such an expert on the subject

Never said I was an expert. Just that everything needed to explain how you get a manual gearbox to WOT-shift was explained already, hence being so blunt. Either accept it or do your own research and prove us wrong. Keeping on asking the same questions and getting the same answer is helping nobody.

perhaps you could explain how the rings in a dog box work which you have completley failed to mention.

Ring gears or just "rings". Please clarify.

Also a H pattern box can run dogs so really has nothing to do with the shifter setup/arrangement

That's correct. As mentioned earlier, dog-engagement gears are not necessary for WOT-shifting, but certainly do help to keep the gearbox in working order.

Could you also explain what is special about the t56 that in stock form allows it to be shifted pretty much instantaneously like a dog which is what im trying to UNDERSTAND not debate. We are talking about making a completley stock t56 do this with the only additions being the shifter and haltech.

The gearbox in stock form has nothing "special" about it. Shifting at WOT with the stock gearbox CAN be done, but you're just asking for trouble (destruction)

Either the shifting needs switches (mentioned above) to help it spark-cut to both disengage the current gear and to help it engage in the next gear.

This is required at bare minimum. Haltech is just a means to spark-cut via switching.

Just trying to get keif to explain to us exactly how its possible rather than random facts that may be true but seem irrelevant...

LOL ok...

[IH8TOADS]

My Opt 5 clutch can't handle a shift that falls back into the peak torque area. Here's a vid of short shifting with the clutch remaining engaged on all shifts and the foot pinned to the firewall. Stock T56. Ralphy's genius ideas at play again :-)

Edited 08/12/15 11:34 PM by IH8TOADS

[barnz]

Bloody hell, we have well and truly established how the load is taken off the box keif...

In a dog arrangment the revs come down as the dogs engage and the revs just get pulled down pretty much. Its a brutal process. In a syncromesh box a cone shaped clutch arangment allows the shafts to spin up to the same speed which is somewhat aided by pushing the clutch in and the revs naturally fall. It just simply takes fkn longer than 2 dog rings smashing into each other and engaging when they line up which happens very quickly.

So how the fark is this overcome with sycros. that's all I want to know lol. I belive its possible. I will always take the word of others in the know but doesnt mean I wont question how/why in the quest to understand...

Toads do you know? Seems like there is still a tiny delay in your vid, not a brutal engagement like dogs. Is the t56 just able to match the shaft speeds very quickly?

Edited 08/12/15 11:43 PM by barnz