The Triumph Dolomite Club - Discussion Forum

Morning everyone, yet another question, hopefully someone has all the specs of Borg Warner automatic gearboxes?

I'm looking at a selection of BW65 gearboxes and know that they are identified by the manufacturer's data plate on the side which is colour coded for car make and then by the first 3 digits for model but what is the correct combination for a BW65 to fit a 1850 Dolomite?

Thanks again,

Phil.

011, 017, 018, 047, 6071 over the entire Dolomite range, and I think 017 & 6071 are for the Sprint but the paperwork isn't that clear, the former up to 10/80, the latter for 10/80 onwards. So that would make 011, 018 & 047 for the 1500 & 1850 but it doesn't specifically differentiate between them although I'm pretty certain 011 is 1850 because I've got one here.

Hi

Which make and model of car would have a BW65 with a green tag with the first 3 digits 009?

Thanks for you reply.

Phil

Walker71 wrote: ↑Wed Sep 19, 2018 12:58 am

Which make and model of car would have a BW65 with a green tag with the first 3 digits 009?

According to the data I have 009 is Triumph 1500TC 10/73-02/76

Hi,

What are the drive ratios for a BW65 from a 1850 Triumph Dolomite?

Thanks,

Phil.

Hi Harvey,

What are the drive ratios for a BW65 fitted to a 1850 Triumph Dolomite?

I am transplanting a Triumph Dolomite 1850 engine and BW65 gearbox into a Morris Minor for my wife and I have the choice of 2 differentials on the shelf, engine pulls well now with a standard 1000 engine/gearbox/diff but 1st gear is pretty much redundant and its revving too high at around 60mph.

I'm going to overhaul the axle, replace all bearings and seals and also fit some cnc competition halfshafts rated at 160 bhp.

The current diff is a 4.22:1 and I have an overhauled 3.7:1 one already.

I would like to be able to compare the standard gearing as is with that of the 1850 engine and BW65 automatic gearbox.

Thanks,

Phil.

Maybe better finding out what the diff ratio is in an 1850 auto, that way you have the same as the dolly

Tony

Walker71 wrote: ↑Sun Oct 07, 2018 3:01 pm

What are the drive ratios for a BW65 fitted to a 1850 Triumph Dolomite?

I'd have to check that in the Workshop Manual which I don't have to hand at the moment, so I'll try to have a look in the week.

IIRC there are only two slightly different sets of ratios on all BW35's, and 65's may all be the same ratios, I don't remember those having different forward sun gears and gearsets.

The diff ratio on an 1850 auto Dolomite is 3.27:1 the same as the Morris Marina.

The 4.22 is definitely undergeared for an 1850! I sold a Dolomite 1500 and autobox to a guy last year to fit to a Moggy, he's done the conversion and run the 1500's end bearings from cruising at 60 for too long! He's now fitted a Wolseley 1500/Riley1.5 diff which may be the 3.7 you have the choice of and it's MUCH better! Whilst the 3.27 is obviously the optimum choice of final drive to use, I think you'd probably have to swap the axle case and shafts for a Marina one to make it fit, I don't think the Moggy case will accept it. then of course, you actually have to FIND a useable 3.27, which is getting difficult, since it is shared with the non O/D Gt6 and very popular as an upgrade on an O/D Gt6 to give it extra long legs.

Steve

Workshop manual gives the following for 1850 auto, 1st 2.39:1 2nd 1.45:1 3rd 1:1. Converter reduction 1-1.91:1

Tony

tony g wrote: ↑Tue Oct 09, 2018 10:05 am Workshop manual gives the following for 1850 auto, 1st 2.39:1 2nd 1.45:1 3rd 1:1. Converter reduction 1-1.91:1

Thanks, that's saved me having to look.

Those are the ratios on pretty much all of them, the different sized sun gear only alters reverse I reckon having had some time to think about it.

Glad to help

Tony

harvey wrote: ↑Tue Oct 09, 2018 4:17 pm

tony g wrote: ↑Tue Oct 09, 2018 10:05 am Workshop manual gives the following for 1850 auto, 1st 2.39:1 2nd 1.45:1 3rd 1:1. Converter reduction 1-1.91:1

Thanks, that's saved me having to look.

Those are the ratios on pretty much all of them, the different sized sun gear only alters reverse I reckon having had some time to think about it.

Thanks for your replies, having to change the tyres anyway and I all ready have a refurbished 3.7:1 diff, just didn't want to have to change either twice.

Anyone recommend a calibration service as I have a couple of spare speedo's? Would like to have one calibrated to suit and swap it when I change engine/gearbox/diff, have seen Speedy Cables on the internet, anybody have any experience with them?

Walker71 wrote: ↑Fri Oct 12, 2018 3:34 pm
Anyone recommend a calibration service as I have a couple of spare speedo's? Would like to have one calibrated to suit and swap it when I change engine/gearbox/diff, have seen Speedy Cables on the internet, anybody have any experience with them?

I've used them quite a lot and can't fault their work but they can be a bit slow with instrument recalibrations. They will often say, with good humour, that the name of the company is "speedy cables", not "speedy instruments".

There's also speedograph-richfield