Engine swap 2500 Vitesse Mk I

[Roger]

Hi All,

1966 Vitesse 2-litre Mk I Convertible:

I have finally found a 2500 engine for sale in Sweden and I consider to do an engine swap (crack in the block on my original 2-litre engine). The 2500 engine number is MG56449E, and the engine does not have inlet manifold, carbs or dizzy. I searched the forums for related topics but I only found this http://forum.tssc.org.uk/topic/146-engine-swap-mk1-vitesse-1966/?tab=comments#comment-977

which ended up as a thread drift about bonnets without answering my questions

So my questions is: Will this 2500 engine fit in my Vitesse Mk I and can I use my existing gearbox? I believe I have to modify the original sump, but is there anything else to consider? I know it would be easier to replace it with a 2-litre engine, but where I live you just have to use what ever you can find! And those 500 extra cc wont do any harm I guess...

Any help and advice will be much appreciated. Thanks in advance,
Roger.

[Pete Lewis]

Yes the origial 2 ltr sump needs a bashing to clear the throw of the crank

The block needs the tappings for the engine mounts the 2500 are on the front timing plate

If the MG 25 is a mk2 you need manifolds  to suit,  if its mk1 then your orig will fit ok

The clutch is the same as 2ltr vitesse ,  the orig gearbox is the weak link , a big saloon box is more bullet proof but needs the chassis rails modifying to slot it in.

With 13 " wheels  the 3.89 diff may be a bit low , a 3.63 from a 1500 spit might be better 

The 2500 mak es a lot of torque and doesnt suit or need   high revs

Just a few clues 

Pete

[JohnD]

The 2.5L (& 2L) was mounted in the saloon canted, that is turned vertically to the drivers right.    If you use the saloon rear engine plate you won't be able to reach the gear stick, with the engine upright in the Vitesse.

And OE intake manifolds are setbto have the carbs horizontal, so on an upright engine theybpoke through the bonnet.   Use OE Bit manifold.

Saloon gearbox needs massive chassis mods.  See Binmans SuperSix webpages.    But a well rebuilt GT6 'box was fine in my old Silverback.

John

[Roger]

Thanks a lot Pete! I do hope it is the Mk II design (?) I do not like the Mk I manifold design. I would rather buy new manifolds than using the Mk I version. My knowledge about the saloons is very limited. Can anyone advice, how do I know if this is a Mk I or Mk II engine? Unfortunately I do not have any pictures of the engine (yet). I realise that my original Vitesse gearbox might have a weakness coping with the extra torque. But if my Vitesse Mk I gearbox fits to this 2500 engine (?) then I promise that I will always drive like my mother. Very very carefully

Br Roger.

[Roger]

7 minutes ago, JohnD said:

The 2.5L (& 2L) was mounted in the saloon canted, that is turned vertically to the drivers right.    If you use the saloon rear engine plate you won't be able to reach the gear stick, with the engine upright in the Vitesse.

And OE intake manifolds are setbto have the carbs horizontal, so on an upright engine theybpoke through the bonnet.   Use OE Bit manifold.

Saloon gearbox needs massive chassis mods.  See Binmans SuperSix webpages.    But a well rebuilt GT6 'box was fine in my old Silverback.

John

Thanks John! I searched for the Binmans webpages but found only bikes. If a Gt6 gearbox will fit, them maybe my Mk I Vitesse gearbox will also fit?
/Roger.

[Nick Jones]

The engine will fit as the cylinder block is functionally the same, but some parts need to be swapped over.

Sump:  The 2.5 sump has a slightly angled base, which doesn't matter very much and is deeper in the front section, which will probably give clearance problems with the  steering rack.  The choices are to remodel the 2.5 sump to clear the rack or to fit the 2.0 sump.  If fitting the 2.0 sump you will have to make some dents in it to clear the longer throw of the big ends for cylinders 1,2 and possibly 3.

Backplate: You need the Vitesse backplate fitted to match the gearbox - easy swap.

Flywheel: use the Vitesse flywheel.  The 2.5 one weighs as much as a small planet  and moves the clutch further back causing all kinds of problems.  Note that you need to fit a Vitesse/GT6 spigot bush in the back of the crankshaft.  The  2.5 crank does have the hole for this.

Front plate:  Has the "legs" for the 2.5 engine mounts.  You need to cut these off or swap the plate from your other engine.  Some Mk1 engines have different front plates - yours probably isn't early enough to be a problem.

Engine mounts:  The bosses on the side of the block are always tapped, so you can bolt your Vitesse engine mount brackets on no problem.

Manifolds:  All 2.5 engines have the Mk2 head so you will need manifolds to match.  The "MG" prefix on your 2.5 engine implies it is a PI engine with the earlier "132" cam, which is good if it hasn't been rebuilt and changed since it left the factory. 1.5" carbs will be a bit small for it, but will work ok with the correct needles. 

Should go very well.  A higher geared diff will help alot, either a 3.63 or 3.27.  If no overdrive then definitely 3.27 - but don't go drag-racing because you'll break it!

 

Nick

[dougbgt6]

22 minutes ago, Nick Jones said:

as the cylinder block is functionally the same

How about converting it to 2 litre with bits from the old engine? Just a thought.

Doug

[Roger]

Thanks Nick for the detailed info! And Doug, I did not think about the fact that I could also build a 2-liter engine with these bits. Brilliant! I have to consider that.

[Nick Jones]

You could convert it to 2L.  The biggest difference I can think of offhand is the size of the headt studs.  Mk 1 are 3/8" and Mk2 7/16".  Best solution is to drill your Mk1 head for the bigger studs, or, I suppose, use the Mk2 head with domed pistons like the later 2L..........

Nick

[Roger]

Finally in my garage! I had to drive 750 miles in total (1200 km) and also a ferry to Sweden to get it. And on top of that it also cost me a new TV for the wife!! Fortunately my oldest son also lives in Gothenburg where I found this engine for sale, so I did not travel only for the engine. I’m very curious what I will find when I remove the cylinder head! Unfortunately there are a few parts missing, most importantly the inlet manifold for the carbs, so if anyone here on the forum has one for sale please let me know. I’m planning to build a 2500 Vitesse with HS6 carbs (Sorry Pete, Strombergs are not an alternative here unless you can sell me an inlet manifold for CD175’s). I would appreciate some advice regarding this item, will it fit? Engine number is MG56449E and the only number I find on the cylinder head is 312388.

https://www.ebay.co.uk/itm/Triumph-2000-2500-TR6-Inlet-Manifold/232759213016?hash=item363187bbd8:g:Y3YAAOSwaZFa3Ix~

Thanks in advance

Edited May 8, 2018 by Roger
Forgot engine number

[Nick Jones]

You need to be a little careful with that inlet manifold.  While most of the Mk2 heads have the same port spacing, some years of US models (TR250? TR6? not sure exactly) are different.  I have no idea why!  They would have been for CD175  carbs though have a feeling that stud pattern for CD175 & HS6 is the same.

The other point to watch is though a manifold from a 2500S saloon will definitely fit the head, the face that mates to the head is machined at an angle so that the carbs sit more or less horizontal in a saloon - which has the engine tilted at ~ 6º.  This means that the manifold tips up at about 6º when mounted on a vertical engine (like Vitesse) and adds to carb/bonnet clearance problems.  If using SUs you need the shorter dashpots from a Dolomite Sprint.

The ideal is probably the right US market TR manifold with the normal port spacings - I have no idea where you'd get one though.  They must be about as a fair few TRs have come back this way and some get converted to PI - creating spare carb manifolds in the process.

The head number you quote is the cast-in number.  There should also be a stamped number, probably 218225

http://www.triumphclub.co.nz/?page_id=653

Engine number suggests the early 132 bhp spec (same cam as Mk2 Vitesse/GT6).  The best one.

Strange rocker cover - from early Vitesse 6 or 2000 saloon?

Nick

[Steve P]

 

On 2/27/2018 at 5:30 PM, JohnD said:

Saloon gearbox needs massive chassis mods.  See Binmans SuperSix webpages. 

John

Having done this to my 2.5 MK1 Vitesse it needed very light fettling around the seam of the chassis.Also a custom mount for the rear.(mine has O/D).And the gearstick is in the same place.

More mods required if you want to use the existing speedo drive because of the position of it.(i went electronic).

Did all that and then it ate a driveshaft at the hub end.(now CV`d).

Steve

[Clive]

I can echo Steves post about gearbox fit, I did it to my vitesse. And I used an angle drive, but made a small cutout in the chassis. Very small IIRC...though I think my gearbox was a tad high at the rear. 

[Guest]

3 hours ago, Roger said:

Finally in my garage! I had to drive 750 miles in total (1200 km) and also a ferry to Sweden to get it.

That's impressive Roger - but of course catching up with your son makes the journey all the more enjoyable !!

I am going to Beaulieu Autojumble, weekend after next, so if there is anything you want me to keep an eye out for please let me know. Perhaps Nick / Steve or Clive can confirm what you actually need and I can then see what's about. Not sure if that will assist but willing to help out if I can.

Regards.

Richard.

[Steve P]

I have an unused Long tract HS6 manifold that has been skimmed to take the angle out,brain fade prevents me from remembering why i never used it,maybe because with Vitesse front and rear engine plates and Carbs with Sprint dashpots i didn`t need to!.

Steve

[Roger]

Thanks a lot for all the advices, much appreciated. I will check and make sure that the engine is ok before I buy inlet manifold. No need to buy one if this one has a crack too… But it seems ok so far. Yes, the rocker cover is probably much older than the engine.

[dave.vitesse]

Most point have been covered so I will not repeat them but, will add the following

If you can not find a suitable 2.5 carb manifold you can still used 150 CDS Strombergs, on a Mk2 manifold, on the 2.5. Though they will restrict the top end air flow to some extent above 3,500 rpm. But loads of low end torque!

Dependent on which manifold you use you may need to shift the starter solenoid as it may be too close to the rear carb float chamber of the HS6. 

If the engine has it's original cam in place, being early, it's the same as the Mk2 GT6/Vitesse. Hence a Mk2 dizzy will match the cam. Your Mk1 dizzy has less advance so OK to use for the moment.

The TR6 HS6 manifold also has an angle on it. So no advantage over 2500S manifold.

The diff is one of the weak points when using the extra torque of the 2.5.

Dave

[dave.vitesse]

Forgot the HS6 Needles. Don't go for the 2500S needles, BDB, as these are too weak for the MG prefix engine. Use BDM or the richer BDC and Yellow springs. If you have free flow air-cleaners you may need Green springs.

Dave

 

[Clive]

17 minutes ago, dave.vitesse said:

Forgot the HS6 Needles. Don't go for the 2500S needles, BDB, as these are too weak for the MG prefix engine. Use BDM or the richer BDC and Yellow springs. If you have free flow air-cleaners you may need Green springs.

Dave

 

The problem (from first hand experience) is the 2500S air cleaner, which is VERY restrictive.I used an S engine inmy vitesse, and just refurbed everything including carbs. (VP2 bearings were easily available too) I did fit a modified Vitesse airbox, with K+N filters inside. But the std BDB needles. It wouldn't rev above 3000rpm as it was going so weak. Quickly noticed, and a swap to Sprint needles had it revving freely. That was a lovely engine despite the very soft cam. Later swapped to a fast road piper cam, which was never as nice to drive

But I blew several 3.27 diffs, partly down to the saloon box with its very low first gear (I wish I had fitted a sprint first gear) but eventually swapped to a 3.63 which survived, and also lasted in my Zetec Spitfire with no ill effects, now taking retirement in a mk3 spit in Belgium (having had a once-over and re-seal)

[dave.vitesse]

3 hours ago, clive said:

The problem (from first hand experience) is the 2500S air cleaner, which is VERY restrictive.I used an S engine inmy vitesse, and just refurbed everything including carbs. (VP2 bearings were easily available too) I did fit a modified Vitesse airbox, with K+N filters inside. But the std BDB needles. It wouldn't rev above 3000rpm as it was going so weak. Quickly noticed, and a swap to Sprint needles had it revving freely. That was a lovely engine despite the very soft cam. Later swapped to a fast road piper cam, which was never as nice to drive

 

The problem with 2500S air cleaner was also my findings. As you say Very restrictive. The TR7 though not the same type has the same problem with the air cleaner as it does with restrictive exhaust boxes. Must have been some BL policy to make quite cars!

Dave

[Mark B]

I have fitted sprint carbs and 2500s inlet manifold to my 2 litre Vitesse. I opted to open up the 2.5 air filter box as I like the way the inlet is centralised feeding both carbs. I also increased the diameter of the intake pipe. The air box is now wider at the bottom tapering up towards the top enough to miss the inner wheel arch without mods,  stub stacks are fitted. The face section of the box is held on by a couple of bolts at the rear so is quick and easy to remove to get to the carbs for balancing etc. without having to remove the hole box.

Mark

[Roger]

Thanks for the pictures Mark, nice car! I havent  decided what carbs to use, its great to get some suggestions.

[Steve P]

Are you taking it to Leatherhead Mark?.

Steve

[Mark B]

Thanks Roger, good luck with the engine.

Hi Steve

Still not on the road belive it or not, only owned it for twelve years, but determined this will be the year.

I will be going to SEM, so hope to see you there.

Mark

 

[Ian Foster]

Mark

I like the look of your air box and can see that you have tried to address supplying equal air feed to each carb. Triumph tried this with many different versions of tubes, holes and lumps on the filter casings, but never really nailed it, in my opinion. I am considering something similar on my Mk2 GT6 to replace K&Ns. Was it a custom fabrication job ?

Roger

Good luck with your Vitesse engine swop.

I have recently modified my GT6 inlet manifold by building up the flanges to allow direct fitment of CD175s, having lost patience with the SAH adapters that have been on the car since I bought in 1977 (photo attached).

I considered a late long branch manifold and have one stashed away for possible future projects, but as others have said this will require modification to correct the 'saloon' angle. I worked with my original manifold as the heater arrangement of the GT6 uses the back of the water jacket pipe to mount the valve and I was trying to keep it original..ish.

Hope this helps

Ian F

White 19 GT6 Mk2 1969

78/00559