Jump to content

3 Rail to Single Rail


Darren Groves

Recommended Posts

You could do what a friend did. Cut the 2 input shafts, and weld what you need together.

OK, not quite as simple as it sounds, but if you have somebody who can to the matchining (male on one part, tight interference fit into a drilling on the other, and then weld with runout kept within factory spec) and it will live. Not sure I would do it to a six cylinder car, but a 4 is OK. He has done almost 100K like that.

  • Like 1
Link to comment
Share on other sites

The 3 rail input shaft I have is needed, as the 3 rail 'box will be going into my Herald at some point in the future, the single rail into the Spitfire project. The correct input shafts seem to be available, so if this is all that is needed to make it fit then I'll just have to go that route. Not the end of the world, I picked up the Gearbox for a good price and expected to have to spend money on it to get it sorted.

Darren

 

Link to comment
Share on other sites

http://www.teglerizer.com/triumphstuff/spit_and_gt6_specs.htm

Says that YD is 1500 RWD 1975 on, with internals the same as Dolly 1850, although not sure if that extends to the input shaft as well. Be aware that this would give you a close ratio gearbox (GT6 ratios), with first being at 2.66:1 instead of the usual 3.5:1. Although I'm sure Mike will advise you on whats best. 

  • Like 1
Link to comment
Share on other sites

Just looked at the to input shafts I have same lenghth, different size mainshaft tip bearing and different syncro ring needed. The fine input shaft needs the later thin ring same external size but bigger hole to fit the bigger cone on the shaft.

Think some of the later coarse spline shafts also used the later syncro ring.

Regards

Paul

 

IMG_20181113_124520.jpg

  • Like 1
Link to comment
Share on other sites

3 hours ago, JumpingFrog said:

http://www.teglerizer.com/triumphstuff/spit_and_gt6_specs.htm

Says that YD is 1500 RWD 1975 on, with internals the same as Dolly 1850, although not sure if that extends to the input shaft as well. Be aware that this would give you a close ratio gearbox (GT6 ratios), with first being at 2.66:1 instead of the usual 3.5:1. Although I'm sure Mike will advise you on whats best. 

1500 and 1850 internals are not the same.  While casing, shafts and change mechanism are the same, the gearsets are different with different ratios.  The 1850 being the same close ratio gearing as the GT6 and Vitesse and also TR7 4 speed.

There are other variations within the extended BL family, especially Marina and Ital which I'm not familiar with.

Nick

  • Like 2
Link to comment
Share on other sites

I purchased a slave 3 rail for some odd parts, someone had spent a lot of money making a repair with a mixture of single rail parts

A disaster , probably why it was in a heap at TRGB , it really confirms some  look similar but there was some real rattling good fit hubs on the mainshaft  and unmatched reverse idler and sleeve tooth count,    heck knows how it ever worked   or not

The mainshaft tip had been cut bored and a slug fitted..loose, which messed the input (stem gear) bore up

Well I kept the cluster and case ,   not a good buy   more   goodbye

Pete

Link to comment
Share on other sites

1 hour ago, Nick Jones said:

1500 and 1850 internals are not the same.  While casing, shafts and change mechanism are the same, the gearsets are different with different ratios.  The 1850 being the same close ratio gearing as the GT6 and Vitesse and also TR7 4 speed.

There are other variations within the extended BL family, especially Marina and Ital which I'm not familiar with.

Nick

Ah yes, I see I've misinterpreted JK's email on that website. So the 1500 RWD is the same as Spitfire/Toledo (which you'd expect).

Process of elimination, might help:

Marina 1300 input shaft has a change in diameter just before the splines (taken from eBay) so it's not that:
marina1300.thumb.jpg.74c50373db8de15d305e77979b9057ec.jpg
TR7 is very very long, see this comparison, Spit right, GT6 middle, TR7 right:
2045810843_SpitGT6TR7001.jpg.8fcba9b4db73c35624de6aad949be229.jpg

So that leaves 1850 Dolly or Marina 1800. This is a comparison of Spitfire and 1850 from this forum thread (https://www.triumphexp.com/phorum/read.php?8,1460769) :
1850vsspit.jpg.653ae49cea04acf378653f9a99411da0.jpg

I'd say that the one you have is longer than the 1850 in this picture. So that leaves Marina 1800? Unless some machining has already been done. Either way, I'm interested to know what Mike says it actually is so do keeps us informed.

  • Like 1
Link to comment
Share on other sites

4 hours ago, Darren Groves said:

The good news is that Mike has confirmed it's a 1500 Gear set in there with a completely random input/first motion shaft, so easily sorted by fitting the correct one. Mike just needs to see the laygear to ensure it's correctly matched and we can the sort what we need.

Darren

 

 

Its quite possible the input shaft was from a Marina box as quite a few Marina based kit cars including the Marlin had Triumph overdrive gearbox conversions done this way and needed  the longer input shaft as they kept the deeper Marina bell housing.

If its 20 splines its from a 1300 Marina and 23 splines is from either a 1800Marina  or a 1700 Ital.

  • Like 1
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...