XP to XR 3speed gearbox upgrade mods needed

[XPFalcon1966]

Hi
I have an XP with a leaking 3speed gearbox and finding it hard to get it in gear.
Thinking of putting an XR 3 speed synchro in.
Does anyone know what has to be modified for it to work?
Is it worthwhile?
Thanks Heaps
Darryl

[Citroënbender]

It’s the “large back” type block, like an XR?

[XPFalcon1966]

I’m not really sure.
It’s an original 170 pursuit.
It has an original 3 speed non synchro gearbox. 4 bolt holes on the top of the gearbox.
Someone told me that it’s best to put a later model gearbox out of an XR falcon.
It’s a much stronger box with synchro in first gear.
Just wondering what modifications I need to make it work for me?
Cheers Darryl

[Citroënbender]

That might be the small bellhousing type block unless it’s a very late XP, if so you’ll not find it straightforward to put the later box in. Having the selector shafts and their bushings rehabilitated could be an easier choice.

[Itsme]

I got caught out once with the difference size bell housing on an XM ute, very frustrating.
Do some measurements to check before proceeding.

[XPFalcon1966]

Thanks guys!!
I will have to look into it more.

[mick taylor]

Originally Posted by XPFalcon1966

Thanks guys!!
I will have to look into it more.

Oh boy !

So much is involved in doing such !
It's just not a direct swap over !

The XR had a non syn 1st box standard and an option of a Syn box as well.

The tail of the box is shorter for the X member of XP and XR on are longer tail !

The XR on 6 cyl has a wide rear housing to the engine block and the XK-L-M-P are a narrow rear housing to the block. and that's just the start of it all !

A mate had had a XP Hard Top from 1980 on and he put a 221 in it and 4sp box. That was the easy way out back then ! for cost as well !

[XPFalcon1966]

Hi Mick
Thanks, Mick, It it really does sound like a lot of work
After Much consideration I have decided to go down the original box.
Don’t want to go down that conversion rabbit hole, sounds like fraught with danger.
Going to get a secondhand box and then possibly get this one done up.
Thanks, Darryl

[39ClevoUte]

Common problem is a worn shifter fork. They just don't push the locking collar in far enough and under load it spits back out. A new fork will push it all the way in.

[Citroënbender]

That’s interesting to learn. I’d assumed it was a problem with where the selector shafts entered the main housing, wearing shaft and bore.

Can the fork tips be built up with bronze (eg MIG bronze wire) or brazing?