Lt77 conversion requirements

Finally went for a drive in the 5 speed today very impressed with how it’s transformed the drive , very smooth .... I need to get a speedo cable made up from speedy cables and then get my speedo head recalibrated....
does anyone know what fixings are used on the cable ends ..... is the head fixing an m12?
And the gearbox end this rover 1056e fitting on the speedycable website ? Also the length required was thinking 60inch , pic of the piece I removed from the lt77 speedo drive
Thanks all
 

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When I converted mine, which was a 3500S, so a manual car already, I used the standard 3500S cable, all I had to do was enlarge the hole in that lower flange so it fitted over the slightly larger LT77 speedo driven gear shaft, and modify the LT77 clamp so it would hold the slightly smaller flange on the 3500S cable.
 
I have put a thick washer between the cable and the gearbox and used the original 4 speed clamp at the moment ....but wanted a more permanent solution , which flange did you enlarge?
Thanks
 
I enlarged the hole in the bottom of the speedo outer cable so it fitted over the LT77 driven gear, and then modified (narrowed the width between) the LT77 clamp so it held the 3500S cable flange.
 
Ok so it goes further down ... good idea ... il do that I think I’ve a few spare cables to try it on .... any idea how much a recal on the speed is as I’ve read on here you had yours done
Thanks again Harvey
 
I did have my speedo head recalibrated by Speedy Cables, but it was about 35 years ago and I can't remember how much it cost.
 
Lots more fun with a manual, isn't it!? :p:cool:
I haven't connected my speedo yet so I'll be watching your progress with interest.
Did you fit a lightened flywheel?
 
Isnt there a way to get a different speedo driven gear into the LT77 output housing to fix the speedo issue? Some makes have several different gears (different no of teeth, but still mesh OK with the driving gear) that they use with different ratio final drives.
I did this conversion many years ago, and about to do it again (with luck!), but that time I finished up with a very heavy clutch - supposedly SD1. When I get started will be asking many questions!
jp
 
Is the primary pinion on a TR7 version of LT77 same size/length as that from an SD1 ?
thanks
jp
 
Next question - what thread are the rear mount rubber bobbins please? I see some that look ok, but are listed as M8, some 5/16 UNF?
thanks
john
 
what thread are the rear mount rubber bobbins please? I see some that look ok, but are listed as M8, some 5/16 UNF?

I would say Met....Mit, (it's no good, I just can't say it), and for 2 reasons, I'd say the LT77 would be too late for Imperial threads, and secondly, they thread into the ally tailhousing, so if they were Imperial they wouldn't be UNF they would be UNC.
 
Been on the home brew H ?

Or maybe those 'flowers' that TRM has hanging up at the back of the shop..... man.
 
"I would say Met....Mit, (it's no good, I just can't say it), and for 2 reasons, I'd say the LT77 would be too late for Imperial threads, and secondly, they thread into the ally tailhousing, so if they were Imperial they wouldn't be UNF they would be UNC. "
My thoughts also....and M8 comes in fine and coarse. One seller on the bay shows 5/16 UNF.
Will have to wait until I have a box in front of me, or somebody with one speaks up.
thanks
jp
 
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