Auto box - big revs

[Stimpy]

I always think that when I'm driving the stag it could really do with a 4th auto-gear. On the motorway anything above 75 mph asks for many thousands of revs from a hefty 3L V8 - and think of the mpg doing 80 down the M40 with the revs close to 3k rather than edging near 5k...

So my question is - has anyone transplanted there autobox for a 4-th gear type? I have no knowledge about auto boxes but is there any way of getting that magic - oh so needed - 4th gear?

Cheers
Steve

[Kevin Garrod]

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Yes yes yes!!

Get yourself a ZF 4 speed auto, not cheap but worth it!!

[Ian B]

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Stimpy wrote:

I always think that when I'm driving the stag it could really do with a 4th auto-gear. On the motorway anything above 75 mph asks for many thousands of revs from a hefty 3L V8 - and think of the mpg doing 80 down the M40 with the revs close to 3k rather than edging near 5k...

So my question is - has anyone transplanted there autobox for a 4-th gear type? I have no knowledge about auto boxes but is there any way of getting that magic - oh so needed - 4th gear?

Cheers
Steve

yes it's the ZF auto box, many have had it fitted and speak highly, Clive tate (see front of mag) can carry out the conversion, cost.............2K:shock:

[sjm]

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Fit a 4 speed box.

That's if you can afford £2,000 +

Or go the DIY route, check out the threads on ZF Auto box.

Steve

[Stimpy]

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Wow - that was a quick response!

Thanks chaps - perfect answering.

I might be making my stag a daily driver so it might be worth doing - although the price means I'd better dig out my piggy bank and start saving now!

Thanks again for the responses - spot on!

[Right - I'll start by searching under the back of the sofa....]

[peter f]

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Steve,
Clive Tate did mine 3-4 months ago. Wow what a difference. It does 33 mpg on a run, and though I will never get the money back, it transforms the way the car performs. It's the way to go!
cheers,
Peter

[turbineman]

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yes it needs a 4th big time what about swap to manual much cheaper than £2k,

how hard is this to do see loads advertised for sale and fairly cheap.

anyone tried this,

regards john

[Kevin Garrod]

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Wot? get lumbered with all the clutch problems, no thanks!

[turbineman]

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i take it thats a no then:shock:?

anyway i got plenty else to sort first!!!

would prefer a manual though.

[GDPR]

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You could go the whole hog like me and fit the ZF 4 speed and the 3.45:1 diff from a 2500 estate - now I get top gear cruise figures of 30mph per 1000rpm.......

70mph is 2300rpm...... and the engine has no problems pulling it

Russ

[Stimpy]

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Thanks again for the help.
Just a quickie - that 2k - is it the bottom line price (ie after labour and tax has been added).

I've already started budgeting in my mind. The missus hasn't complained yet so that's hurdle number one done. Other hurdles include "justification", "find the money", "You could go to barbados for 2 weeks including hotels and flights for that", etc etc.

Currently waiting for a Tony Hart rad to become available (a certain "wheeler dealers" has created a waiting list there!). So get that out of the way - get Tony's opinion and then overcome those hurdles....

Someone said 2.5k revs at 70mph - just been out for a run in the lovely June evening and I get 40mph with those revs. Certainly a 'hmmmm' moment!

[singapore stag]

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kryten wrote:

You could go the whole hog like me and fit the ZF 4 speed and the 3.45:1 diff from a 2500 estate - now I get top gear cruise figures of 30mph per 1000rpm.......

70mph is 2300rpm......

Russ

Are the 2500 estate diffs more reliable (whine wise) then the Stag ones? How do they compare if fitted with a normal 3 speed BW.

Thanks,

Sukh.

[GDPR]

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Mine is dead quiet Sukh - the 2.5 PI kicked out 132 bhp, not a million miles from the standard Stag lumps output, so I'm not expecting any shortening of it's lifespan.

The 2500 estate is a direct swap unlike the saloon diff - the backplate is the same as the Stag so no bodged gaskets and a direct bolt-on swap.

On a standard Borgy, expect the revs to drop by a minimum of 10% so instead of the usual 3000rpm at 60mph, it should drop to between 2600 and 2700rpm.

A good estate diff can be had for £125 or £150 and would only take a couple of hours to swap out (mine took just under 3 hours but I had to change my propshaft as well (worn UJ).

1st gear is now a 50mph job, 2nd is good for 80.........

[singapore stag]

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Nice one Russ! just what I wanted to hear, my diff sounds like a Banshee giving birth to quads ( aptly described by someone on this forum on noisy diffs ).

One last thing, how do you identify a 2500 estate diff? I know its to do with the colour of the bolts on them or somthing to that effect.

Sukh.

[GDPR]

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Diff no that starts MGA is what you're after - if the driveshaft flange nut has red paint on it, it's a 3.45:1 ratio (although the MGA prefix denotes 3.45) .............