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Is a Triumph overdrive tranny all that?

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Almost 20 years ago I put a Spitfire J-Type overdrive in my Midget 1500. It was a bit of work because a chassis cross-member in the transmission tunnel needed to be cut out and replaced with reinforcement under the floor, but it was _so_ worth it when it was all done. That Midget was my daily driver, and the O/D unit was absolutely trouble-free. Also, because the Midget shared the MGB's switch-gear, the overdrive switch was already built into the wiper switch... pull back to engage, and flick forward to disengage... it was great!

The only awkward moments were when I would occasionally forget to disengage the the overdrive as I pulled to a stop on a long highway drive, then take off again when the light turned green. First and Second gears were normal enough, but then I would shift to Third and a second later the O/D would kick in, lugging the engine. A second after that I would sheepishly flick the lever forward, and accelerate away normally again. I did that with my girlfriend in the car, and she thought we'd just suffered some sort of horrendous break-down. She married me anyway. /bcforum/images/%%GRAEMLIN_URL%%/wink.gif

Scott
 
2wrench said:
Absolutely, Glemon. Holy Toledo! I think what I'm
gonna do with this one is take it to a shop.
I purchased then asked questions (sounds kinda dumb,
doesn't it?) Says a total breakdown is necessary but
I think he supplies a needed mainshaft. This fellow
has some very good comments about doing business with
him. I'm always a bit suspicious of those comments,
though. Are they, like, his brother; wife; son-in-law?

Anyway, please do advise me as soon as your unit arrives,
I am excited to see what you find. I think Julian also
bought one as well.
Click to expand...

Yes, I bought one too ... looks like he has done very well out of us all told /bcforum/images/%%GRAEMLIN_URL%%/smile.gif

I get very good vibes from him, and 100% feedback is impressive, especially on used parts. We shall see, but I am optimistic.

The "tearing down" of the gearbox doesn't worry me too much: just how hard can it be???!!!! (Famous Last Words!)
 
Sorry, Julian, but when the Forum talks, I listen.
Seems to me the tranny has been suggested best left
to the pros...and not that it would stop me... but I'll
certaily consider it. If you do this, maybe I'll follow
your lead, if you know what I mean. You post some
pretty good pics....and, yeah, I do get a good feel
from this guy as well. Let's hope we're correct
 
skucera said:
Almost 20 years ago I put a Spitfire J-Type overdrive in my Midget 1500. It was a bit of work because a chassis cross-member in the transmission tunnel needed to be cut out and replaced with reinforcement under the floor, but it was _so_ worth it when it was all done. That Midget was my daily driver, and the O/D unit was absolutely trouble-free. Also, because the Midget shared the MGB's switch-gear, the overdrive switch was already built into the wiper switch... pull back to engage, and flick forward to disengage... it was great!

The only awkward moments were when I would occasionally forget to disengage the the overdrive as I pulled to a stop on a long highway drive, then take off again when the light turned green. First and Second gears were normal enough, but then I would shift to Third and a second later the O/D would kick in, lugging the engine. A second after that I would sheepishly flick the lever forward, and accelerate away normally again. I did that with my girlfriend in the car, and she thought we'd just suffered some sort of horrendous break-down. She married me anyway. /bcforum/images/%%GRAEMLIN_URL%%/wink.gif

Scott
Click to expand...

Thanks for sharing this one. I love the story.
 
skucera said:
but then I would shift to Third and a second later the O/D would kick in, lugging the engine.
Click to expand...
Don't know if he still does, but there was a fellow selling a logic device on eBay to prevent this. In essence it was a "holding relay" and a momentary contact for the operating switch; so every time you shift, the holding relay would drop out and turn off the OD. Then you would push the button when you wanted it on again.
 
Julian, its not the tearing down that concerns me it is putting it back together, still I think I would like to try.

Greg
 
I took lots of stuff apart as a kid. Somehow a lot of it didn't work when I put it back together.

But I did take an overdrive apart once and I got it back together and working. Read the manual!

Bryan
 
Got a commitment today that the overdrive unit has been
shipped. I think it will take a couple weeks.
Hmmmm. It will probably be here, like, way ahead of
schedule. Still got the engine in parts and the
machine shop's on vacation, of course, till the early part of next year. Sounds so far off, huh?

It's like I want to order parts, but know I can't -- and
waiting when the time comes is gonna just kill me.
Think I'll start meditation now.....
 
Should have done this sooner. Ladies and Gentlemen:

Find attached a photo of the rebuilt upgrade unit that
me; Greg and Julian purchased. Please view it
and answer this question, if you can.

Once this unit is installed, will my original
unit identifiers still be in tact on my tranny?
This is what I had hoped for in doing this overdrive
upgrade. I am so ignorant; but I do think that this is
a bolt-on type of deal to my original tranny and most
everything will be the same, cept the shaft size and
whatever else is going into the case, plus an adapter
that goes onto the case. Anybody following my ramblings,
here?

db24_01.jpg


Whaddayasay?
 
Oh, sorry about the pic size, it is all that was offered
from the net. Might need a magnafying glass, huh?

As I look again, I fear I might be losing some detail;
numbers on the tranny, with this upgrade. I just can't tell.
 
Yes, the serial or commission number on the transmission is stamped on the left side where the clutch shaft goes through the bell housing.
 
If you're wondering about the serial number on the trans. staying the same, it will. It is stamped on the bell housing as Ray said. That will not change when you add the overdrive. I'm not sure what your concern is. If you are wanting all the numbers to be as original they will be except that if your car was not originally shipped with OD that will be obvious. The commission number had a O suffix if the car had overdrive. If your car doesn't have the O then whether the number on the box is matching or not, it will be obvious that the OD was added.

Personally, I don't care if the numbers match or if a car originally had OD or not - just trying to understand and answer your question.

Bryan
 
My OD arrived today from New Zealand, I have not inspected it yet--but I'll let you know after I take a look, he said 3-4 weeks, and I think it was closer to two, so far so good.
 
I'm new here, however, I will comment on this deal. I think the best way to get an overdrive, is to pick up the phone and order it from England, was like 720 bucks to your post office 2 yrs. ago, arrived in 5 days, and was done by ex Laycock employees and looked like new, and has worked perfectly. This was for the OD only. Also, they put the right speedo gear in the OD, if you buy it elsewhere, what gear is in the overdrive? The other speedo parts are pricey also, bout 200 bucks. Also, if you are putting the OD shaft in your trans, are you going to rebuild the trans? There are some very poor trans parts out there, sychros, layshafts, etc. You need to know who sells the good parts that work and keep working. The standard reply when a part does not work is, "nobody else has ever had a problem". This is not a fun job to do 2 times. Also, I assume you will be replacing all the clutch parts, a small book could be written on this topic.
 
Right on, Greg! I am waiting with bated breath for
you to post anything about this upgrade.
I'm excited.
 
TheSearcherMan said:
I'm new here, however, I will comment on this deal. I think the best way to get an overdrive, is to pick up the phone and order it from England, was like 720 bucks to your post office 2 yrs. ago, arrived in 5 days, and was done by ex Laycock employees and looked like new, and has worked perfectly. This was for the OD only. Also, they put the right speedo gear in the OD, if you buy it elsewhere, what gear is in the overdrive? The other speedo parts are pricey also, bout 200 bucks. Also, if you are putting the OD shaft in your trans, are you going to rebuild the trans? There are some very poor trans parts out there, sychros, layshafts, etc. You need to know who sells the good parts that work and keep working. The standard reply when a part does not work is, "nobody else has ever had a problem". This is not a fun job to do 2 times. Also, I assume you will be replacing all the clutch parts, a small book could be written on this topic.
Click to expand...

Well, speaking for my own situation, my transmission and clutch have recently been overhauled, so no need to do that again. The NZ guy is supplying the correct speedo parts: this is an aspect that worried me, so I was quite specific about asking him that. He also supplies the correct mainshaft for the job.
 
BryanC said:
... The commission number had a O suffix if the car had overdrive. If your car doesn't have the O then whether the number on the box is matching or not, it will be obvious that the OD was added.
...
Click to expand...

I am close to certain my car had OD fitted when it was shipped from the factory, and it has an LP suffix, no "O". My car is a little odd as it was one of the Belgian built CKD cars, though.
 
BryanC said:
If you're wondering about the serial number on the trans. staying the same, it will. It is stamped on the bell housing as Ray said. That will not change when you add the overdrive. I'm not sure what your concern is. If you are wanting all the numbers to be as original they will be except that if your car was not originally shipped with OD that will be obvious. The commission number had a O suffix if the car had overdrive. If your car doesn't have the O then whether the number on the box is matching or not, it will be obvious that the OD was added.

Personally, I don't care if the numbers match or if a car originally had OD or not - just trying to understand and answer your question.

Bryan
Click to expand...

I'm a bit hung up on originality, I suppose. At the
same time, I am willing to make some changes, obviously.
I guess it's all in how far you'll go.

Like friends told me when my engine blew: Hey, just
put a small block Chevy or a Ford engine in it. Cheaper.
More horsepower. Same/similar weight. Will fit. Easier
and chaper to buy parts.

If it's just about....just about a car that drives,
the mods can take us a number of places. An individual
choice. For me, this one mod is desirable; make, model
and period correct.
 
I think the difficult part is getting the rear bearing off/on, other than that, it's not to bad. Oh, and there is one snap ring that is just plain difficult. I guess you know what you have to do with the interrupter switches?
 
Julian,

If it matters to you, order a Heritage Certificate from the British Heritage Motor Centre

https://www.heritage-motor-centre.co.uk/shop/heritage-certificates/index.html


The certificate will tell you what came on the car as it left the factory including (I believe) engine number, gearbox number, options like OD, wheels ,etc.

The certificate might be cool even if the originality of the OD doesn't matter to you.

Bryan
 
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