Stag conversions - Paul531
Been looking at Triumph Stags

Many say converted to Rover V8 3.5

Cost / originality aside,

whci is better

a Stag with Triumph 3.0 - often 3 speed auto

or a 5 speed Rover V8?

I understand that the Rover V8 weighs less?



Paul {Forest of Bowland}
Stag conversions - daveyjp
The major fault with the Stag was it's engine - 2 BL 4 cylinder engines bolted together is not an ideal solution. Everyone said it should have had the Rover V8 from the beginning, but no one listened. Go for the Rover V8 - if it was good enough for MG it will be good enough for the Stag.
Stag conversions - Paul531

Thats what I read too, seen a nice Stag - Rover 3.5 engine - but I want a S111 E-Type really, but cannot afford one -

£15k min for owt any good {2+2}
£35k for roadster.

S1 and S11 E - Types preferred by some I know- but only any good if you're pint sized - S111 is the only one with a decent winscreen {roadster} / headroom {coupe}

I keep playing the Lotto

But is it not on these pages somewhere that someone likens the Jaguar V12 {single cam of course} power plant to three marina engines bolted together ?

Since Marinas needed a re-build after 20k, does the Jag V12 need a rebuid after 7k?

The guy who did the E-Type on Top Gear - Best car in the World - Ever - did a naff job of it.

Could JC not have done for the E-Type what he did for IK Brunell, afterall , no one had ever heard of IK Brunell before {except yours truly - B. Eng Hons} and everyone knows of the E-Type

Paul {Forest of Bowland}
Stag conversions - Altea Ego
AS its a classic, then i would always try and go for an original spec model. In this case tho the original engine was such pants (specially the cooling) that for practical ownership the rover lump is the way to go. Getting bits for the orginal engine is getting hard now as well I understand - (specially cooling bits!)

So if its for investment - get an orginal
If you want to use it and have fun - get a conversion model.

( I remember watching Hart Racing running a stag at thruxton many years ago )
Stag conversions - Galaxy
I seem to remember reading that some people also fitted Mazda Rotary Engines into Stags.

I wouldn't think they were any better than the one's they replaced, though.
Stag conversions - Chas{P}
This question is answered more than comprehensively on the Stag Owners Website. See:

The much maligned 3.0 OHC V8 can be made reliable and numerous solutions have been developed to overcome initial design problems. Just look at their technical index to see what's covered.

Investment wise I would always go for an original V8 Mark 2 auto in a nice colour. Again on the SOC site there is a buyers guide.

Good luck

Stag conversions - Maz
Unless the previous owner has made a modification to the original engine, it'll still have the legendary marginal cooling.

This means that the head gasket will go, probably not for the first time, so will not be able to be 'skimmed' anymore and you'll need a new head.

After you've spent your money you'll still have an engine with a marginal cooling system.

It's nice to think that the original engines will hold their value better, but historically it's a much better idea to buy a car to drive. They are NOT good investments.

I'd go for a modified original or the Rover V8.

Stag conversions - Steve S
I'd agree with most of these and I can't really see that having the Rover lump in a Stag that was in every other way original would harm it's price much.

If that is the case, let some purist pay the premium and have the inevitable aggro. The Rover engine was (and still is) the engine the Stag should have had anyway.

Good luck, a true classic car.
Stag conversions - John S

I ran a Stag many years back. Avoid the auto - it's a flaky BW 35 and is far too low geared - get the manual/OD model for preference.

Yes, many fitted the Rover V8 engine, due to problems with the original Stag engine - usually cooling or head gasket problems. It has those wonderful angled head studs.

I believe Rover engined cars are less valuable. The other problem is that the Rover engine has a very differnt power curve - it peaks at lower revs than the original and so does not suit the auto cars. It's also lighter and may benefit from suitable suspension mods.

As it's now going to be used as a low mileage 'classic' I'd look for a car with the original engine, but which had been properly sorted by a specialist. But, keep your fingers crossed and your eye on the temperature gauge when it's hot weather!


John S
Stag conversions - Dizzy {P}
I agree with John re: the Borg Warner 35 auto box. A far better auto box is the BW65 that was fitted to the Stag from late-1975, however I still prefer manual+overdrive in the big Triumphs.

I converted my Triumph 2500 from BW35 to manual+OD about six years ago and it transformed the car -- wish I'd done it years ago! I went for the Laycock J-type (as fitted to Stags from 1973) as this is a stronger and generally better unit than the earlier A-type.

A very useful and interesting book called "Original Triumph Stag" by James Taylor (ISBN 1-901432-24-6) can often be found in discount book shops. They are usually no more than a fiver and very well worth it.

Getting back to the original question -- the Stag engine suffered from much more than cooling, such as timing chain problems and valve spring breakage. These problems spoilt a really nice car (and a really nice engine!) but almost all should have been sorted out by now on any Stags owned by enthusiasts, though perhaps not on those that have been in storage for a long time.

The problems with the cooling system were, according to James Taylor, that the alloy head castings had flaws which could block the waterways and that the pump was mounted quite high and would fail to circulate the water if the level dropped, so leading to overheating. Also the temperature warning light was deleted because it was temperamental! James Taylor says that the troubles are now well understood by Stag specialists and all can be "permanently overcome" with modifications.

As always with aluminium alloy heads, it is essential that a corrosion inhibitor ('antifreeze') is used summer and winter. James Taylor says that failure to do so can lead to corrosion which deposits small particles into the cooling system, leading
eventually to blockage.

The bottom line is that I would look for a car with the original Stag engine, though I wouldn't turn down a Rover-engined car if everything else was right. The Rover engine is an excellent unit and was originally a Buick engine, the design of which was based on a BMW engine.

Stag conversions - Dude - {P}
I seem to recall that a major problem with the Stag, with the original 3 litre motor, that has not been mentioned in earlier threads, was that it broke crankshafts, when revved much above 3000 rpm, due to it whipping as a result of insufficient main bearings in the original design spec.
Stag conversions - John S

Yes, that reminds me - in addition to its other problems, bearing wear and low oil presure is another Stag problem. As you say the main bearings particularly are marginal in size for the engine! Definitely one to look for when checking out a car. Unfortunately, the cars don't have an oil pressure gauge as standard, so make sure the oil light stays out at idle when thoroughly warm. Be suspicious if the idle is set on the high side.


John S
Stag conversions - thebouncingbunny
original is best.the 3 litre v8 is in effect 2 dolomite 1850 engines .a friend has one with a man overdrive ,quite a beast.if these engines are looked after properly it should pose no probs.rover v8 cars are worth less.this is not a cheap car to run or repair so buy wisely.....classic cars can bite....ouch!
Stag conversions - madf
having had a Triumph 2.5PI and had perennial problems with the dirveshaft splines locking (despite regreasing) I would suggest a Stag with a Rover engine (more power) and the original siding driveshaft splines is going to be probelematical.

I worked for BL at the time of eth Stag launch and recal a 3feet long fax to Lord Stokes by a VERY p-d off owner of a new Stag who could not get any garage to sort out its (many ) problems.

(Junk then and junk now imo.. but it takes allsorts..etc:-)

Stag conversions - Dave N
Didn't think they had faxes when the Stag was launched. Are you sure it wasn't a telex?
Stag conversions - Dizzy {P}

I agree that Triumph driveshaft splines can lock if power is maintained whilst cornering, however this fault was almost overcome during the T2000 Mk1 days (pre-1969). Admittedly Triumph found it necessary to have three goes at getting a suitable spline fit! Too loose and you get drive train clonks, too tight and the splines lock when cornering under power.

For the uninitiated, if the splines lock going into a corner and then unlock, the rear of the car can suddenly dip mid-corner. This can feel uncomfortable -- and could be quite worrying if you are near the limit of adhesion, though I haven't heard of it ever causing loss of control.

A driveshaft modification to totally remove the problem is marketed by Chris Witor but this is a bit expensive and probably not worthwhile for ordinary road-going cars.

My 1972 Mk II 2500 (ex-PI) does *very occasionally* stick, but not enough to cause any concern -- the car just gives a slight twitch. The grease needs to be right for the job.
Stag conversions - Paul531

"I worked for BL at the time of eth Stag launch and recal a 3feet long fax to Lord Stokes by a VERY p-d off owner of a new Stag who could not get any garage to sort out its (many ) problems"

The Stag came out in the late 60s - yeah ?

That's 25 years before the fax machine !!!!!!!!!!!!!

Bid BL even have phones in then days?

Was the meaasge not transmitted by smoke signal, carrier pigeon or two bean tins and a lengt of string?
Paul {Forest of Bowland}
Stag conversions - hxj

I realise that the Stag is old, but the fax machine pre-dates it by over a hundred years.

Even transatlantic faxes were operational just after the first world war.

The originals are probably still working now, unlike most Stags!
Stag conversions - 3500S
If you are going to drop a Rover V8 into a Stag, go for an EFi (if you can find one), good for 175 Bhp+ and you'll need to put in an LT77 5-speed as well. A good donor in this case would be a mid-1980s SD1 V8; there should be a few around. The Rover V8's only weakness and this is a minor one is that the oil capacity is quite small. It is a light, all alloy engine and it suits the Stag well. It would certainly weight less than the 3-litre and therefore the car might handle better.

The only thing is I'm not sure if the real diff for the Stag can take it though.

Of course, in hindsight Triumph should have taken the Rover V8 from the start but it typifies the rivalries between Triumph and Rover in the late 1960s. Not to mention Rover P8 and P9 that Jag sat on. Not an illuminating time in car history.
Stag conversions - Dude - {P}
Whilst on the subject of Rover V8 engines, can any of you B.R. Tech-heads confim whether the Rover engine was fitted to the MGC V8 ??? Thanks in anticipation.
Stag conversions - DavidHM
An MGC V8, if such a thing exists, would be a conversion based on the six-cylinder version of the MGB that was sold in the late 60s. I think it used the 3.0 engine from the big Austins, which was a bit too heavy for the small car's handling.

Highly unlikely as you'd find one as a B would be a better and cheaper donor car.

There was an MGB V8, factory built from about 73 on, and that did have the Rover V8 engine. I'm not sure what the state of tune was like and there are some original chrome bumpered cars out there. Not many though, and all the factory cars were GTs - any roadster will be a conversion of a 1.8 litre B.
Stag conversions - 3500S
Indeed a Rover V8 can be shoe-horned into a MGB.

The 1970s version is a 150Bhp tune, don't know why but it's not difficult to extract more.

The 'heritage' MG they did in the 1990s was a 200Bhp (Rvoer V8 EFi) version, very, very sought after now, many have been re-imported back from Japan, they are usually British Racing Green.

Being a proud Rover V8 owner, I let these guys loose on my 3500S and it was a complete pleasure. They let you hang around whilst they do the work and show you what they are doing. Absolutely superb place and you could write on the back of a postage stamp what they don't know about the Rover V8.

Stag conversions - Paul531


you're right about the fax machine, but the fax as we know it was a 1980s invention?

Is this the longest post ever?

The first facsimile equipment for use in communications was the chemical telegraph invented by Alexander Bain (1810-1877) in 1842 and patented during the following year. This consisted of a metallic contact resting on a moving paper slip saturated with an electrolytic solution. The wire and the tape formed part of an electric circuit and when current flowed, discoloration of the tape occurred.

It is thought that the first working model of Bain's chemical telegraph was constructed and operated at about the time of the World Fair held in London in 1851. At this fair a second facsimile machine was demonstrated by Bakewell, who had been granted the relevant patent in 1848.

In principle the two machines operated in similar fashion using damp electrolytic paper as a recording medium and relied for transmission on a scanning stylus being in physical contact with the text of the message, the text being in relief form with raised lettering. Both systems also depended on associated pendulums and electromagnets for synchronisation. The Bain machine was essentially a flat bed machine while in Bakewell's model the relief text and receiving electrolytic papers were wound on drums.

For many years the development of facsimile equipment was directed towards improving the mechanics of the scanning and reproduction functions. In 1865 the first working trials for a commercially viable facsimile machine was set up in France by an Italian, Caselli. Shortly after this Meyer facsimile machines were also tried out in the French telegraph systems.

Although the Caselli and Meyer machines had been brought into service there were still two major areas of difficulty to be investigated: synchronisation and contact transmission. A practical method of synchronising the early facsimile machines was finally worked out, and culminated in the La Cour tuning fork controlled motor synchronisation.

Facsimile was first used commercially in France as an electromechanical telegraph. In 1870 there were some 17 Meyer facsimile instruments in service in the French telegraph system in conjunction with 4000 electromechanical telegraph machines. It appears that the facsimile facility was used to a large extent by the French government and to carry information relating to stockbroking. The main advantages seen at this time were the virtual elimination of errors in transmission and the availability of a facsimile signature.

The contact type transmitters used up to the early years of the 20th century were not satisfactory and limited the speed of transmission via facsimile. This was overcome through the development of a suitably sensitive photoelectric cell by Dr Arthur Korn of Germany in 1902, and his application of this cell to phototelegraphy work. The technique of this system was to transmit light through a photographic negative of the original, wound on a glass cylinder, to a photocell which converted the light pulses to electrical signals. The receiving medium was sensitised paper and the picture was reproduced in positive form. By 1910 Korn had established phototelegraphy links from Berlin to Paris and London, and in 1922 successfully transmitted by radio a picture from Rome to New York. In 1926 a commercial radio link for facsimile working was opened between the London office of the Marconi Wireless and Telegraph Company, and the New York office of the RCA.

The need to have material photographed to provide a negative for transmission, and the consequential high cost of the equipment developed on this principle, led to further research, and a system of transmission based on reflected light was evolved. In 1935 the Associated Press of the USA installed a country-wide network based on this system.

By the 1920s pictures for publication in newspapers were being transmitted around the world. Later developments of the service in the 1930's included the introduction of weather maps and wire photo services. Technology had improved sufficiently beyond the late 19th century equipment to ensure that facsimile was a technically viable proposition even though the basic techniques and concept were unchanged.

Among the later adaptations of facsimile service by a telegraph company was that of the Western Union in the 1930s when they made facsimile machines available in public places for the transmission of messages to the nearest Western Union office. The message was then forwarded from the office in the normal telegraph manner. Unfortunately this system proved prone to vandalism and was phased out. Western Union was involved in another similar venture: "Desk Fax" introduced in 1948. Using this system private companies who rented transmitters were able to send short messages via a Western Union telegraph office.

The main area in which facsimile proved successful in augmenting telegraph facilities was in the transmission of photographs i.e. phototelegrams - mainly newspaper pictures, but also pictures of documents, machine drawings and fingerprints. This service grew from the start of the New York - London link in 1926 and continued to thrive. By 1950 access to 24 countries was available and in 1963 the Post Office phototelegraphic system was operating services to and from 56 European terminals and 38 extra-European terminals. In January 1976 these figures were 47 and 51 respectively to a total of 65 countries.

The success of phototelegraphy was not reflected in other uses devised for facsimile. Attempts to introduce home news broadcasts in manuscript form and thus bring facsimile into the residential market failed. Such systems were tried as early as 1929 in America and throughout the 1930s. Once television was introduced there was no possibility of facsimile competing.

As a telecommunications medium facsimile remained from the 1930's to the early 1960's essentially a system for specialised applications with sophisticated expensive machines - the two main sections of use being in distributing weather charts and in the newspaper industry.

Although suitable telephone coupling devices were available from the 1930s it was not until the 1960s that relatively cheap facsimile machines were available for connection to the PSTN. Growth in the market was prompted by declining postal services in the USA, and in Japan by the pictorial nature of the alphabet. These new machines became known as document facsimile machines and were used for transmitting handwritten, typed or printed text and drawings. A contributory factor to the late development of a simple dial-up facsimile unit was the relatively late stage at which solid state techniques were introduced to the facsimile system.

Europe lagged behind the USA and Japan, but early growth followed agreed standards on machine design by the International Telegraph and Telephone Consultative Committee (CCITT). The introduction of Group 1 standard in 1968 was a significant step in the development of facsimile, despite slow and unreliable terminals and lack of full compatibility. It took 6 minutes to transmit an A4 page, but the machine stimulated interest in the concept of sending text and graphic material by telephone around the world instead of heavy reliance on the postal service.

A Group 2 standard was agreed in 1976, which halved the time of transmission to 3 minutes and improved quality with a scanning density of 100 lines per inch. But the density remained unsatisfactory for sending documents containing small print and the time for transmission still meant that a 10 page document took half an hour to receive.

A further CCITT standard was agreed in 1980 for Group 3 machines, which used digital transmission techniques and took less than one minute per page with an improved scanning resolution of 200 lines per inch. All were compatible and could communicate with most Group 2 machines regardless of supplier.

Paul {Forest of Bowland}


Value my car