Section : Gearbox

Clutch, gearbox, overdrive, propeller shaft.

1500/3 rail gearbox

Posted By : Marc Crook, 21-Nov-2003, 07:21pm

got a mk4 with a 3 rail gearbox with d type overdrive. considering fitting a 1500 engine. can this be done with the 3 rail/d type or does it need to be upgraded with the 1 rail/j type?
any info would be well appreaciated.

Followups :

1500/3 rail gearbox

Posted By : James Lavery, 22-Nov-2003, 03:41am

I fitted a 3 rail gearbox to my 1500 and you need a special clutch plate that is slightly bigger but still has 10 splines as opposed to the 20 splines on the single rail. If memory serves me.the pressure plate is the same. Your existing propshaft should fit ok as you would only need to change it for a shorter one to accomodate a single rail box. I have a spare clutch plate if you are interested. Leave a message and i'll send my email address.
Good luck Jim.
1500/3 rail gearbox

Posted By : David Rumens, 23-Nov-2003, 01:45pm

Yes you can fit the 1500 on a 3 rail gearbox.

Infact Triumph used the same combination of a 1500 engine and a three rail gear box driving the rear wheels on the early (1973/1974) 1500TC RWD saloon and 1500 Toledo (1970/1974).

The different number of splines between the three and single rail gearboxes means a different clutch plate has to be used

Later 1500TC (1974/1975), 1500 Toledo (1974/1975) and the 1500 Dolomite used the single rail gear box.

The 1500TC and 1500 Toledo clutch plate that fits the three rail has a Standpart No. 155569.

Hope that helps

Dave
- 1500/3 rail gearbox
  
  Posted By : Nigel Gibbins, 23-Nov-2003, 05:18pm
  
  Triumph also did this in the late MkIV spitfires that were being shipped to the USA - this effectively made them Spitfire 1500s but officially they were still MKIVs.
  
  The combination worked so well, the 1500 was born from it albeit with a stronger gearbox (the single rail). The adaptor plate is available at all the usual places and is part No GCP103. About Â£30.
  
  Cheers
  NiG
  - 1500/3 rail gearbox
    
    Posted By : David Rumens, 23-Nov-2003, 08:00pm
    
    True Nigel, as the change over point for the gearbox was around 1975 the early US 1500 Spits had the three rail set-up.
    
    Many thanks for pointing out the later part number, GCP103, which was a Unipart item. As we both know this replace the original Stanpart No.
    
    I have used the three rail on a some what tweaked 1500 engine in a Toledo many years ago. With up rated dampers and springs, the Leyland ST anti-rollbar kit back and front. It all worked very well and was great fun.
    
    Many Thanks
    
    Dave
    - 1500/3 rail gearbox
      
      Posted By : Tim Willis, 24-Nov-2003, 10:46pm
      
      Did you know? That clutch plate is a 1098 Morris Minor item!
      I needed one a while ago when I put a 3railOD box in my 1500 (got the box for Â£30 so I wasn't complaining) at the time the retail on the friction plate alone was Â£60!! I don't think that's the case now though
      - 1500/3 rail gearbox
        
        Posted By : David Rumens, 25-Nov-2003, 07:40pm
        
        Thanks useful info. Looking through the Rimmer price list it gives Â£42.89 Inc VAT. Maybe cheaper elsewhere.
        
        Thanks
        
        Dave