Converting to overdrive gearbox
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canberra triumph
- Groupie
- Posts: 27
- Joined: Sat Sep 27, 2008 6:06 am
- Location: Mount Gambier Australia
Converting to overdrive gearbox
Hi all, I currently have a bog standard manual 4 speed gearbox in the 2500, and have a chance of picking up an overdrive gearbox. Is it a simple matter of removing the old & bolting up the new, or is it a bit trickier than this?
Simon
Mount Gambier Australia
1976 2500TC - Jolly Green Giant
Another Green 1976 TC, auto this time, as a project
1976? Spitfire - Little Red
Mount Gambier Australia
1976 2500TC - Jolly Green Giant
Another Green 1976 TC, auto this time, as a project
1976? Spitfire - Little Red
Re: Converting to overdrive gearbox
Hi Simon, from NZ. same bell housing etc.You'll have to wire it up of course but no big job.
There are 4 spacers which fit between the floor pan and the gearbox crossmenber,Try and get them with the gearbox if you can. If not and you can't find any I can give you the demensions ,they could be made fairly easily, The mounting plates which go through the floor with the threaded parts which hold the gearbox up will probably also be too short with the longer spacers. Again ,if you can try and get them with the 'box.
While you've got the 'box out you may want to think about replacing the clutch unless you know it's a good one. The o/d gearbox is b.....y heavy. You don't want to take it out again!!
There are 4 spacers which fit between the floor pan and the gearbox crossmenber,Try and get them with the gearbox if you can. If not and you can't find any I can give you the demensions ,they could be made fairly easily, The mounting plates which go through the floor with the threaded parts which hold the gearbox up will probably also be too short with the longer spacers. Again ,if you can try and get them with the 'box.
While you've got the 'box out you may want to think about replacing the clutch unless you know it's a good one. The o/d gearbox is b.....y heavy. You don't want to take it out again!!
1976 2500 TC. converted to S specs.
Lots of bits
1999 BMW Z3.
2006 BMW 325ti.
Hopefully not needing too many bits.
.
Lots of bits
1999 BMW Z3.
2006 BMW 325ti.
Hopefully not needing too many bits.
.
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TedTaylor
- Senior Member
- Posts: 1670
- Joined: Sat Dec 06, 2008 11:27 pm
- Location: Forest of Dean (Gloucestershire)
Re: Converting to overdrive gearbox
If you were in the UK I would suggest uprated studs/spacers from CW but probably not cost effective from Australia.
'A' type overderive uses a relay. 'J' type does not though personally I would wire in a relay anyway to take the switching load off the gear lever switch contacts.
Ted
'A' type overderive uses a relay. 'J' type does not though personally I would wire in a relay anyway to take the switching load off the gear lever switch contacts.
Ted
Member 4473 1990
1964 2000 period rally look alike AFH 849B
Morris 1800 London-Sydney/Monte/WCR NAM 616G
Mk1 PI Estate SCG 115G
2500 Estate WDE 76K RBRR 2014
1964 2000 period rally look alike AFH 849B
Morris 1800 London-Sydney/Monte/WCR NAM 616G
Mk1 PI Estate SCG 115G
2500 Estate WDE 76K RBRR 2014
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Mike Stevens
- Site Admin
- Posts: 3649
- Joined: Mon May 08, 2006 9:50 pm
- Location: South Oxfordshire, UK
Re: Converting to overdrive gearbox
The spacers are only needed if you're fitting a 'J' type overdrive box. An 'A' type uses the same rear mounting system as manual with no overdrive.
As already said, apart from wiring, it's all a nut and bolt job. Heavy though!
Cheers,
Mike.
As already said, apart from wiring, it's all a nut and bolt job. Heavy though!
Cheers,
Mike.
(South Oxfordshire)
Register Member No 0355
1971 2.5PI Saloon Sapphire blue
1973 2.5PI Saloon rust some Honeysuckle
1973 Stag French blue
(1949 LandRover which is now back to its original light green!)
Register Member No 0355
1971 2.5PI Saloon Sapphire blue
1973 2.5PI Saloon rust some Honeysuckle
1973 Stag French blue
(1949 LandRover which is now back to its original light green!)
Re: Converting to overdrive gearbox
Hello Simon,
also, do try and get the gear lever with the switch (Mounted in the gear lever knob if you are not aware of that) with the gearbox.
Alec
also, do try and get the gear lever with the switch (Mounted in the gear lever knob if you are not aware of that) with the gearbox.
Alec
0465
MK1.5 2.5 P.I.
Jaguar MK 2 (Long term restoration, nearing completion.)
MK1.5 2.5 P.I.
Jaguar MK 2 (Long term restoration, nearing completion.)
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Mike Stevens
- Site Admin
- Posts: 3649
- Joined: Mon May 08, 2006 9:50 pm
- Location: South Oxfordshire, UK
Re: Converting to overdrive gearbox
Oops, I forgot that bit. Very poor, especially considering I changed the gearlever on the PI only the other day!Alec wrote:gear lever with the switch
Cheers,
Mike.
(South Oxfordshire)
Register Member No 0355
1971 2.5PI Saloon Sapphire blue
1973 2.5PI Saloon rust some Honeysuckle
1973 Stag French blue
(1949 LandRover which is now back to its original light green!)
Register Member No 0355
1971 2.5PI Saloon Sapphire blue
1973 2.5PI Saloon rust some Honeysuckle
1973 Stag French blue
(1949 LandRover which is now back to its original light green!)
-
canberra triumph
- Groupie
- Posts: 27
- Joined: Sat Sep 27, 2008 6:06 am
- Location: Mount Gambier Australia
Re: Converting to overdrive gearbox
Thanks for all info, will be very useful when (if) I manage to get the gearbox 
Simon
Mount Gambier Australia
1976 2500TC - Jolly Green Giant
Another Green 1976 TC, auto this time, as a project
1976? Spitfire - Little Red
Mount Gambier Australia
1976 2500TC - Jolly Green Giant
Another Green 1976 TC, auto this time, as a project
1976? Spitfire - Little Red
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andy harrison
- Newbie
- Posts: 18
- Joined: Thu Apr 17, 2008 8:31 pm
Re: Converting to overdrive gearbox
...finally, don't forget the speedo cable is longer for the overdrive gearbox ... Andy