UN1027 Gearbox upgrade with Master Unit

[MarkKassim]

My 2^nd gear synchro failed and as I have increased my torque output to around 300lb/ft I decided upgrade to a UN1027 to replace my standard UN1016 in the SE. As these are quite hard to find in good working order, Dave Changes helped me out by reconditioning an old unit he acquired. Dave rebuilt all the shaft assembles and crown wheel checking the synchro’s and hubs replacing if showing signs of wear, he installed new drive shaft seals and my original bell housing, so it was ready to install.

I bought a new pair of gear change cables to suit the late style V8 cross gate, and routed them as shown

If anyone has a shot of a factory setup that would be good, I routed the new cables to keep beds to a minimum. I made new brackets and positioned them on the side of the gearbox.

Then came the interesting part of re-designing the Master Unit to work with this setup as the late V8 master units are hard to come by.

Taking these two diagrams from the manual I reworked my existing master unit

 

 

I wanted to make the gear selection as free as possible, so I used a selection of bearing types to cover all the different axis type and load.

I 3d printed the bearing sleeve to help guide it along with a groove in the map bearing. I also printed  side stop , both in hard plastic PTEG.

I wanted to create a self centering action at Master Unit to assist the springs at the gearbox so I have set-up springs on each end of the main shaft to oppose each other and allow a centre position to be set(after working out a procedure)

 

 

 

 

 

 

 

 

 

 

 

The translation movement can be seen in the video.

I have to confess there was a great deal of trial and error with multiply test runs and modifications to put this together, but been running for about a year now and ran at Castle Combe

Its holding up well but I am always looking for refinement, I’ve widened the gate 2 or 3 times as I’m afraid of miss selecting on the track ,I did this by changing the pivot point on the bell crank . I find the gate is slightly closer between  1^st to 3^rd than 3^rd to 5^th. I got it pretty good now and you can see it in action on my castle comb video which I will post soon  

 

Mark K

[Erikl]

So the internals are stock or did Esprit Changes install the stronger main shaft?

[CHANGES]

6 hours ago, Erikl said:

So the internals are stock or did Esprit Changes install the stronger main shaft?

All stock 027 ,  As per the V8 spec.. 

[Jacques]

I have a brand new late type gearmaster, and I borrowed it to PNM for a period so they could draw it up and make replicas for production and sale. As I understand it, they want to create a complete set with gearmaser, brackets, cables and the endhousing as well. You may call them and ask how it's going on that project.

Kind regards,

Jacques