Borg warner T56

[gartrac]

Has anyone considered or actually fitted a Borg Warner T56 6 speed gearbox to a 351 Winsor ratios are as follows

2.66 - 1.78 - 1.30 - 1.00 - 0.74 - 0.50 T56 Dodge Viper ratios

3.27, 1.98, 1.34, 1.00, 0.68 Tremec 3550 ratios

Firstly is there a hydraulic bellhousing available, Winsor to T56
What final drive ratio would be suitable
Speedo drive is electronic, is there an after market speedo available

Finally would it be a practical option

Your thoughts please

Pete

[mark]

hi pete is the t56 from the viper or corvet both are under the t56 bannar but are differant specs dose the box have a bellhouse on, there are two or three ways of sorting the problem , it would take me a mounth to type an explanation my be you could ring

[wilf]

My first thought is "why on earth would anyone want 6 speeds with the torque of a 351W??"
The only reason they fitted this box to the Viper and 'Vette with it's hugely overdriven top gear was to not sully their overall mpg figures (CAFE???) and get past the drive-by noise tests. They are not needed in real life.
My second thought is " wonder what back axle ratio you would need?"

I use a tremec TKO (same ratios as 3550) and 3.31:1 rear end. With hindsight, I should have gone for the TKO2, which has a less tall overdrive (around 0.8 I think). Overall gearing in 5th works out for me at around 33 mph/1000rpm - the engine will still pull in 5th, it's a great gear for cruising, but after all the noise and great acceleration in 4th, the standard 5th ration (0.6 seems really tall. Hairsplitting really, but such small things do get under your skin in the end - one day I know I'll swap out that 'box!! (Don't tell the wife).

Standard issue back end for those using 4 speed toploader boxes is 2.88.
You need to sit down and work on a spreadsheet to give you speeds in various gears at various rpms to see if it's worth doing.

Can' advise on a bellhousing - sure someone here could help, or talk to Mike Forte in the USA. Don't worry about electronic speedos - you can rig them up using magnets and pickups on the propshaft. You might even be able to use the electonic sender in the box, ask Speedy cables.

HTH

Wilf

[gartrac]

Wilf
Just did some calculations using Bowtie's spread sheet based on your 33 mph per 1000 revs

Axle ratio of 4.27 works well, gives 34 mph per 1000 revs in sixth gear with all other gears sensibly spaced, any idea which road car used this ratio?
Found it listed on a jaguar web site as an optional ratio

[graham]

Wilf, My BWT5WC is 0.63 in 5th, Tall as you say but I do have a 3.54 ratio diff, So should be good out the block and have an OK cruise, what ya reckon?

Graham

[wilf]

Gartrac - Jag book says 4.27 diff fitted to early (series 1) XJ 2.8 litre 4 speed manual and auto (not manual with overdrive tho').

WIlf

[wilf]

Graham - I find 1st a tad too low, 5th a tad too high. Tremec ratios go 3.27, 1.98, 1.34, 1, 0.68. Not sure of world class T5 ratios, but you can probably go from there.

Wilf

[gartrac]

Wilf

Below is an extract from http:tigersunited.com it's a US based forum dedicated to the Sunbeam Tiger It contains information which may be of use to all of us, obviously the information contained is Tiger orientated.

Basically what the guy is saying is that a US Dana44 axle is dimensionally exactly the same as a Salisbury 4HA with all components interchangable, the only difference being that the Dana44 uses 3/8 carrier to crownwheel bolts whereas the 4HA uses 7/16 but step down bolts are available to carry out conversions. I have confirmed this information via email with the forum editor

What this means to me is that any ratio used in a Dana44 can be used in 4HA.
This axle appears in many US vehicles including the Jeep Cherokee, which just happens to use a 4.1:1 ratio
Hope you find the following information useful
Pete



Another often discussed issue is limited slip differentials. I will try to cover the one option I am most familiar with, the DANA 44, with both with my personal thoughts and experience.

The DANA 44 rear end was the standard one that fit in many US vehicle, like a Jeep, just make sure you get the correct number of splines.

There is an alternative, and that is the DANA 44 made in England, by Salisbury. The same company that made the Tiger axle, and the Jaguar's. Jaguar used these units, and they bolt right in. Salisbury and DANA are the same company. All parts are the same, except for one thing. The holes in the DANA that the ring gear mounting bolts pass through are larger in diameter. In fact, they are the SAME size as used in your stock 2.88 rear end.

When LAT offered the US unit, they required a differential gear set change to a US made Ford gear, which was not available in the stock 2.88, which uses smaller bolts.

Step-down bolts are available in case you want to use a higher rear end from the US, but with the wide ratio change, it is doubtful you will want to go to the trouble. But, you can.

If you do decide to go this way, look for that Jag DANA-Salisbury (same company) LSD with the holes already matching your gears. I wish I could tell you which Jaguar had this unit, but mine came from a tranny/axle shop. You could inquire at an idependent Jag mechanic.

Another option, to retain your 2.88's, which match the wide ratio gear set discussed under "Gear Box", is to have the US DANA 44 carrier bolt holes machined out to fit the stock Tiger bolts. Caution, this is NOT a hand drill process, as the bolt circle and spacing must match the original. Use a machine shop with a milling machine.

[wilf]

Gartrac - you are right, there is similarity between the OE JAg and Dana units, I think, (and this is really dredging up some old info from my memory) that they were actually used in place of the Salisbury units on some jags. Another way to tell if it's a Dana unit is the lack of an oil drain plug - again - I think.

Anyway - this is making the whole subject far too complicated for a simple soul like myself, especially when the likes of Dangerpus Davies is just heaving a whole un-recon'd diff (with smelly oil) into his cobra 2cv. Maybe we make a simple thing too complex sometimes?? After all, they are only cars! (did I really type that?).

Wilf

[gartrac]

Wilf

You cannot be serious where's your sense of adventure? or are you of an age which is ready to conform? Myself I've always liked a challenge and building a hybrid diff sounds like fun and you must admit a six speed gearbox would be different

Going to collect a 351 Winsor in the morning perhaps that will get your blood flowing again

What state is your car in have you started stripping yet ready for paint?

Please call me Pete, Gartrac is just a log in name

Pete